Seismic Cluster Analysis From Burma-Andaman - West Sunda Arc

This article was downloaded by: [Mukhopadhyay, Basab]
On: 13 September 2010

Access details: Access Details: [subscription number 926840111]
Publisher Taylor & Francis
Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-
41 Mortimer Street, London W1T 3JH, UK
Geomatics, Natural Hazards and Risk

Publication details, including instructions for authors and subscription information:
http://www.informaworld.com/smpp/title~content=t913444127
Seismic cluster analysis for the Burmese-Andaman and West Sunda Arc:
insight into subduction kinematics and seismic potentiality
Basab Mukhopadhyaya; M. Fnaisb; Manoj Mukhopadhyayb; Sujit Dasguptaa
a
Geological Survey of India, Central Headquarters, Kolkata, India b Department of Geology &
Geophysics, King Saud University, Riyadh, Kingdom of Saudi Arabia
First published on: 13 September 2010
To cite this Article Mukhopadhyay, Basab , Fnais, M. , Mukhopadhyay, Manoj and Dasgupta, Sujit(2010) 'Seismic cluster
analysis for the Burmese-Andaman and West Sunda Arc: insight into subduction kinematics and seismic potentiality',
Geomatics, Natural Hazards and Risk,, First published on: 13 September 2010 (iFirst)
To link to this Article: DOI: 10.1080/19475705.2010.494014
URL: http://dx.doi.org/10.1080/19475705.2010.494014
PLEASE SCROLL DOWN FOR ARTICLE
Full terms and conditions of use: http://www.informaworld.com/terms-and-conditions-of-access.pdf

This article may be used for research, teaching and private study purposes. Any substantial or
systematic reproduction, re-distribution, re-selling, loan or sub-licensing, systematic supply or
distribution in any form to anyone is expressly forbidden.
The publisher does not give any warranty express or implied or make any representation that the contents
will be complete or accurate or up to date. The accuracy of any instructions, formulae and drug doses
should be independently verified with primary sources. The publisher shall not be liable for any loss,
actions, claims, proceedings, demand or costs or damages whatsoever or howsoever caused arising directly
or indirectly in connection with or arising out of the use of this material.
2010, 1–32, iFirst Article
Seismic cluster analysis for the Burmese–Andaman and West Sunda Arc:
insight into subduction kinematics and seismic potentiality
BASAB MUKHOPADHYAY*{, M. FNAIS{, MANOJ MUKHOPADHYAY{

and SUJIT DASGUPTA{
{Geological Survey of India, Central Headquarters, Kolkata 700016, India
{Department of Geology & Geophysics, King Saud University, PO Box 2455,
Riyadh 11451, Kingdom of Saudi Arabia
(Received 13 April 2010; in final form 3 May 2010)

Downloaded By: [Mukhopadhyay, Basab] At: 14:02 13 September 2010
The Burmese–Andaman Arc System (BAAS) and the West Sunda Arc (WSA) in
NE Indian Ocean are well known for their high seismic hazard and tsunami
potentiality. Seismicity is caused by eastward subduction of the Indian plate to
intermediate focal depths below the BAAS, but the penetration depth goes even
deeper to about 500 km below the WSA. The seismicity map and its correlation to
crustal and mantle faults for this extensive plate margin are presented. This is
achieved by using frequency–magnitude relationship to select larger (mb 5.0)
and comparatively well-recorded events from the available earthquake catalogue
that span for a period of little more than a century (1906–2008). Barely 14% of
the events qualify the treatment, and the events so selected are subjected to cluster
analysis using a statistical function ‘point density’. The clusters found for the arc
demonstrate significant relationship to subduction geometry in their respective
areas; 11 out of a total of 13 clusters commonly originate below the fore arc.
Earthquakes within the individual clusters have linear fractal geometry consistent
with the traces of seismogenic surfaces that actually produce them. Correlation of
clusters to seismologic depth sections and the composite results derived from 518
CMT solutions of earthquakes establish a close spatial relationship between the
shape and orientation of the clusters with stress axes and regional tectonics. This
provides a three-dimensional perspective on the stress distribution within the
respective clustered seismic zones. Seismic potentiality for five most conspicuous
clusters is also inferred.
1. Introduction
The Burmese–Andaman Arc System (BAAS) and West Sunda Arc (WSA) together
constitute a subducting plate margin in the NE Indian Ocean, nearly 2800 km in
length, that serves as the tectonic link between the Western Pacific Arc System with
the Himalayas. BAAS and the WSA have the following tectonic domains: (1) a
northernmost segment of BAAS in Burma where a subduction zone is clearly
discernible in a land environment delimited by Eastern Boundary Thrust (EBT); (2)
further west, the trench zones of Andaman and WSA where the Indian plate
*Corresponding author. Email: basabmukhopadhyay@yahoo.com

ISSN 1947-5705 Print/ISSN 1947-5713 online ª 2010 Taylor & Francis
http://www.tandf.co.uk/journals
DOI: 10.1080/19475705.2010.494014
2 B. Mukhopadhyay et al.
subducts; (3) outer sedimentary ridge of Andaman–Nicobar–Nias Islands in between
trench and the arc, followed by a continuous volcanic arc from Sumatra to Burma
with active Barren Island volcano and dormant Narcondam in the central part and
many dormant volcanoes in Burma; (4) Andaman back-arc spreading ridge (ASR)
underlying the Andaman Sea between Alcock Rise (AR) and Sewell Rise (SR)
relating to the oblique convergence of the Indian plate at the Asian continental
margin in the east; actual spreading occurred through several short leaky-
transforms, producing the ‘pull-apart’ Andaman basin in southern half of the
BAAS; (5) further south is the intense seismic zone of the WSA with volcanism in
Sumatra (figure 1). Sixteen hinge faults (figure 1) across the trend of the arc with
Figure 1. Tectonic domains in the Burmese–Andaman Arc System (BAAS) and the West
Sunda Arc (WSA) in NE Indian Ocean. AR: Alcock Rise; ASR: Andaman Spreading Ridge;
B: Barren Island volcano; BS: Belt of Shuppen; DF: Dauki Fault; EBT: Eastern Boundary
Thrust; MR: Margui Ridge; N: Narcondam volcano; SR: Sewell Rise. The locations of two
great earthquakes from 2004 and 2005 are shown.
Seismic cluster analysis for the Burmese–Andaman and West Sunda Arc 3
fixed western end marked by our earlier study (Dasgupta et al. 2003) have delimited
the entire study area into several blocks of individual seismic characters.
The arc is unique in several ways. First is the intense seismic and tsunami hazard
potentiality of the arc; the last example was the 2004 Sumatra earthquake.
Seismically, the arc is not equally active throughout; a stretch of nearly 800 km
between coastal Burma and the Gulf of Martaban is seismically almost passive.
Second, 40% of the arc lies within the Burmese mainland where the Indian plate
currently subducts to almost 200 km depth. The Neogene tectonics in central Burma
is controlled by the India-Indochina oblique convergence, which is in response to a
major Miocene regional plate kinematic reorganization (Bertrand and Rangin 2003).
Third, the ASR underlying the Andaman Sea relates to the oblique convergence of
the Indian plate at the Asian continental margin (Curray et al. 1979, Mukhopadhyay
1984). Fourth, the subduction depth in central Andaman extends to about 220 km
depth (Dasgupta et al. 2003), but the subduction proceeds to about 500 km depth
below the WAS further south. Fifth, the arc houses several active to dormant
volcanoes, including the active Barren Island volcano in central Andaman. In the
present study, our aim is to search for spatial seismic clusters in the intense seismic
zones of the BAAS and WSA, in order to gain an understanding on the relationship
of potential seismic clusters to structural elements of the subduction zone. In spite of
more than 100 years of instrumental recording in the region (the first seismological
observatory in SE Asia was established in Calcutta as early as 1897), a major
limitation in the study is the non-uniform status of seismic monitoring for the arc as
a whole, in particular, for the lower-magnitude shocks. This is an outcome of the
typical geometric orientation of the arc, most of which lies offshore, whose remote
islands locate far off from the mainland of SE Asia. These factors introduce
inconsistency and incompleteness in any earthquake catalogue, resulting in inherent
uncertainty in the search for ‘long-term earthquake clustering’ (Kagan and Jackson
1991), no matter what methodology is adopted. Notwithstanding these limitations,
we present here an analysis of seismic clusters for the BAAS and WSA, and also
investigate their respective stress characters and seismic potentiality.
2. Seismic data treatment and analysis

It is known that similar events occurring close together in space produce spatial
clusters; particularly, moderate to large magnitude earthquakes often occur in
spatial seismic clusters. A seismic cluster is suspected in a region if it consists of
multiple events with a magnitude greater than a threshold value originating within
an acceptable time period. Any statistical treatment for cluster analysis essentially
therefore depends on the completeness of the earthquake catalogue (Ansari et al.
2009). The earthquake catalogue used in the present study (source: ISS, ISC and
NEIC-USGS) for the BAAS and WSA consists of a total of 13,057 earthquake
records for the period of 1906–2008 covering a rather wide range of magnitude (2.7
to 8.6) with focal depths extending to as deep as 500 km. Both single and cumulative
earthquake frequency curves are constructed using the catalogue data. The b-value
of earthquakes with mb 4.0 calculated by the regression method is 1.0382
(figure 2(a)). Only 1752 events of magnitude 5.0 and above in the catalogue actually
qualify for cluster analysis. Of these, barely 47 seismic events occurred prior to 1964,
with a magnitude-frequency break-up as follows: 11 events in the magnitude range of
5.0–5.5, 20 events in the magnitude range 5.6–6.0 and 16 events of magnitude
exceeding 6.0. Earthquake frequency in the lower-magnitude range (mb ¼ 5.0–5.5)
shows a clear increase postdating 1964 (table 1) as a consequence of an increase in
the number of monitoring stations. The selected events exhibit a smoother
cumulative frequency curve (figure 2(b)) with a b-value of 0.9731 calculated by the
regression method; this is similar to the global average of b-value of 1.0. Table 1
earthquakes, classified according to their magnitude, are superposed on a generalized
tectonic map for the BAAS and WSA (figure 3).
Though several visual clusters are apparent on the map (figure 3), the following
spatial statistical functionalities are applied on the dataset in table 1 to constrain
their configuration and extents:
Figure 2. Frequency magnitude relationships for: (a) 13,057 events of magnitude mb ¼ 2.7 and
above as listed in catalogue, and (b) 1752 events of mb ¼ 5.0 and above. The respective a are b
values are given.
Table 1. Earthquakes for the Andaman–Burmese arc classified according to their magnitude
and frequency (used for cluster analysis).
Earthquake magnitude (mb) range Number
5.0–5.5 1430
45.5–6.0 241
46.0–6.5 60
46.5–7.0 10
47.0 11
Total 1752
Figure 3. Epicentral map for the Burmese–Andaman and West Sunda Arc, period: 1906–2008.
AR: Alcock Rise; ASR: Andaman Spreading Ridge; BS: Belt of Shuppen; DF: Dauki Fault;
EBT: Eastern Boundary Thrust; RF: Renong Fault; SF: Semangko Fault; SR: Sewell Rise; SSF:
Shan-Sagaing Fault; VA: Volcanic Arc; WAF: WEST Andaman Fault; WST: West Sundra
Trench. Tectonic features are adopted after Curray et al. (1982) and Dasgupta et al. (2003).
. A point density function is applied to constrain the extent of the clusters. Point
density is a classical spatial statistical tool to identify areas where data points
are concentrated more or vice versa. To calculate the point density, the
distance between the adjacent earthquakes is measured, and a mean distance
(*8 km) is calculated. Half of the mean distance (i.e. 4 km) is taken as the
radius of the circular neighbourhood. The point density is then calculated as
the total number of earthquake epicentral points that fall within a circular
neighbourhood with a specific radius (in this case 4 km) divided by the area of
the neighbourhood. A factor resulting from the size of the earthquake is also
introduced for deriving the point density value, e.g. 6 points are counted
instead 1 for an earthquake of magnitude 6 in the selected neighbourhood.
This is done to offer more weight to larger earthquakes in the calculation. The
measurement is then carried out in an overlapping grid pattern where the
centre of the circle has been moved across the map (both along latitude and
longitude) by a sliding distance of 4 km. The calculated point density value is
stored in a grid point at the centre of the circle. The resulting values obtained
by this sliding grid process have a mean (M) of 0.0027 and standard deviation
(SD) of 0.008772. The areas with anomalous point density (value 4 (M þ 2
SD), i.e. 0.020244) have been marked as zones of spatial clusters and shown as
closed grey polygons (figure 4). This process identifies 13 numbers of spatial
clusters of variable sizes with numbers C1 to C13 across the entire study area.
. Comparative statistics between clustered and non-clustered events presented in
figure 5 show that almost half the population (table 1) actually originates
within the cluster domains. The figure also illustrates their respective single and
cumulative frequency–magnitude relationships. The ‘b’ value calculated by the
regression method for the cluster zone is somewhat lower (0.8195) than that for
the non-cluster zone (0.9967). However, this apparent increase in b-value is
probably attributable to data inhomogeneity, rather than any true significance
in data coverage for smaller-magnitude shocks.
. The geometric configuration of the clustered and non-clustered earthquakes is
further constrained by fractal analysis to understand the cause–effect
relationship between the occurrence of seismicity and the underlying processes
that produce them. Further, once the fractal or scale-independent nature of
occurrence of seismicity is established, the ‘fractal dimension’ gives the exact
geometric relationship between the earthquakes points and the underlying
causative surfaces. The Box-counting method (Feeder 1988) is used to calculate
the fractal dimensions. The seismicity points are overlain with a grid of square
boxes (pixels), which progressed from the smallest to successively larger boxes
by combining the pixels in an up-scale manner (Cheng 1999). The numbers of
boxes (Nn) of size ‘rn’ required to cover data are plotted on a log–log scale as a
function of ‘rn’. To denote the distribution as fractal, ‘Nn’ with a characteristic
linear dimension greater than ‘rn’ must satisfy the relation Nn ¼ C/NnD, where
‘C’ is the proportionality constant, and ‘D’ is the fractal dimension. ‘D’ is
calculated as factor log(Nnþ1/Nn)/log(rn/rnþ1) (Turcotte 1997). The seismicity
data for both clustered and non-clustered domains (the plots of log (Nn) versus
log(1/rn)) give straight lines (right panel in figure 5). These plots indicate that
the seismicity of both cases obeys scale-invariant fractal geometry, but the
causative processes that generate such geometric configuration are different.
The seismicity in a cluster indicates line fractal geometry with fractal
Figure 4. Seismic cluster analysis results for the Burmese–Andaman and West Sunda Arc
using data plotted in figure 3. In all, 13 clusters (C1–C13) are detected; see text for discussion.
dimension 1.059, whereas the non-clustered seismicity designates a point

fractal geometry with fractal dimension 0.8796. This also implies that the
seismicity points in clusters are arranged to form a linear pattern on the map,
Figure 5. Frequency–magnitude distribution and fractal plots for the clustered and non-
clustered events; see table 1 for their magnitude distribution.
analogous to the traces of major seismogenic surfaces represented as a

curvilinear line. Strain release by well-connected seismogenic surfaces at depth
control the orientation of the clusters. On the contrary, such linear geometry is
absent in case of non-clustered earthquakes with fractal dimension (0.8796),
which indicates agglomeration of points. The disposition of such point fractals
is not directly controlled by any seismogenic surface at depth, instead
indicating sporadic strain release.
The visual relationship, thus illustrated in the foregoing section between seismic
clusters and tectonic features, shows their significant distribution largely in the fore-
arc for this extensive plate margin but to a much lesser extent with the ASR.
3. Discussion on cluster characteristics

3.1 Burmese Arc Clusters
Clusters C1, C2 and C3 are recognized for the Burmese Arc (figures 4 and 6(a)); these
are located in north to north-central Burma in the zones of moderate seismicity.
Earthquake parameters of the clusters (earthquake statistics embodied in a cluster,
magnitude and depth ranges, length of the major axis) are given in table 2. Of these,
cluster C2 is the largest with a maximum number of earthquakes; it is elliptical in
shape with a strike length of 130 km, trends north-east and is thus sub-parallel to the
local structural orientation of the arc. C1 is a small elliptical cluster in the north of
Figure 6. (a) Tectonic map with results of CMT solutions for the three clusters, C1–C3, for the
Burmese Arc. Digits refer to CMT solutions indexed in table 4. Grey circles are epicentres of
earthquakes with mb 5. Notice that thrust mechanisms dominate in all three clusters, where
the P–T axes are orientated NE–SW and NW–SE directions. Seismological depth sections in
BAAS: across the clusters (b) C1, (c) C2 and (d) C3. DF: Dauki Fault; EBT: Eastern Boundary
Thrust; SF: Sagaing Fault; VA: Volcanic Arc.
Table 2. Earthquake parameters defining the clusters.
Number of Range of Depth Length of major

Clusters earthquakes (mb 5) mb range (km) axis (km)
C1 11 5–6.2 9–43 58
C2 26 5–6.3 69–152 130
C3 10 5.1–5.3 60–126 64
C4 12 5–6.2 12–44 60
C5 10 5–8 20–60 55
C6 30 5–6.6 5–44 121
C7 13 5–5.3 15–39 43
C8 37 5–5.4 10–36 122
C9 225 5–6.1 3–128 324
C10 130 5–7.3 21–95 202
C11 16 5–6.1 30–68 55
C12 24 5–5.6 22–33 135
C13 343 5–8.9 1–105 460
Burma. C3 is a north-trending elliptical cluster located south of C2 in the same

structural trend. While C2 and C3 clusters originate from the subducting Indian
plate (refer to the corresponding depth sections in figures 6(c) and 6(d)), cluster C1 is
from the overriding Burmese plate (figure 6(b)). None of these clusters, however,
shows any association with the Burmese Volcanic Arc, which implies their tectonic
origin, rather than their volcanic affinity.
The clusters C1–C3 are separated by lithospheric hinge faults, where subduction
penetrates to depths of 150 km at the location of cluster C1 to 200 km at cluster C3,
but then diminish to 160 km to the immediate south (Dasgupta et al. 2003). The
average dip of the Benioff zone below the three clusters ranges from 428 to 508 E
(figure 6). Most of the Burmese Arc seismic potentiality is therefore expected at these
locales where the clusters are seen. Note that the remainder of the Burmese Arc for a
distance of 1000 km up to north Andaman (where the next neighbouring clusters C4
and C5 are seen) is a cluster-free region (figure 4), as signified by its rather low level
of seismicity. This is probably an outcome of passive tectonic process where the
hanging lithospheric slab is being dragged northward through the surrounding
lithosphere, as postulated by Le Dain et al. (1984). A somewhat analogous ‘low
seismic’ region and an example of time-dependent earthquake occurrence are known
for the Lower Rhine Embayment (Faenza et al. 2007).
3.2 Andaman Arc Clusters

Seismic clusters C4–C9 are located between central and south parts of the Andaman
Arc (figures 4, 7(a) and 8(a)). As before, the earthquake parameters of the clusters
are also indexed in table 2. All of them are shallow depth clusters but contain higher-
magnitude shocks (often exceeding mb ¼ 6.0, sometimes as high as mb ¼ 8.0).
Clusters C4 and C5 are located over the Andaman fore-arc (figures 7(b) and (c)),
whereas cluster C6 is found at the south Andaman trench (figure 7(d)) (this is similar
to cluster C12 seen for the West Sunda Trench; see below). Clusters C7 and C8 are
correlated with the ASR (figures 7(a), (e) and (f)). Cluster C9 is the longest of all; it
has a strike length of 324 km, contains maximum number of earthquakes and is
clearly associated with the West Andaman Fault and its southern continuation to the
Figure 7. (a) Tectonic map with results of CMT solutions for clusters C4–C6 below the
Andaman fore arc and clusters C7 and C8 below the ASR; see table 4 for results of the CMT
solutions. Composite CMT is in the inset with grey colour circle for P axes and black circle for
T axes. Other symbols are as in figure 6. Thrust mechanisms dominate in the Andaman fore
arc, while normal mechanisms dominate the ASR. Notice that P–T axes are orientated E–W
for the fore arc but N–S for the ASR. Seismological depth sections in BAAS: across the
clusters (b) C4, (c) C5, (d) C6, (e) C7 and (f) C8. ASR: Andaman Spreading Ridge; B: Barren
Volcano; N: Narcondam; SR: Sewell Rise; VA: Volcanic Arc; WAF: West Andaman Fault.
Figure 8. (a) Cluster 9 skirting the Sewell Seamount, where a nascent rift was described
elsewhere (Mukhopadhyay et al. 2010). Other symbols are as in figure 6. Cluster 9 typically
demonstrates normal solutions for the rift, whereas strike-slip mechanisms correspond to the
regional faults transverse to the rift. T axes are orientated WNW–ESE, suggesting the rifting
direction perpendicular to it. (b) Seismological depth section across C9 and (c) summary plot
for focal mechanism stress axes. SFS: Semangko Fault System; VA: Volcanic Arc; WAF: West
Andaman Fault. The black dotted line in the depth sections traces the top of the subducting
plate; the trajectories are from our earlier work (Dasgupta et al. 2003).
Semangko Fault in Sumatra (figures 7(a) and (b)). The penetration depth of the
subducting Indian plate in central and south Andaman extends from 130 to 220 km,
where the dip of the Benioff zone varies from 308 to 458 E (Dasgupta et al. 2003).
Such large variations in both the penetration depth and dip angle of the Benioff zone
are typical of plate kinematics in the central and southern parts of the Andaman arc.
3.3 West Sunda Arc Clusters

Seismic clusters C10–C13 are seen in offshore Sumatra (figures 4 and 9(a)). As
before, the earthquake parameters of the clusters are indexed in table 2. These are
shallow to moderate depth clusters with a high seismicity. The configuration for all
four clusters follows the structural outline of the outer sedimentary arc of the Nias
and other islands. Seismically, this presents one of the most destructive regions in the
world, where the 26 December 2004 Sumatra earthquake (Mw 9.3) and 2005 Banyak
Island earthquake (Mw 8.7) hit. Cluster C13 is the widest of all in this zone
(figure 9(a)) with a strike length of 460 km. Clusters C10 and C13 have earthquakes
belonging to both plates (figures 9(b) and 9(e)), whereas cluster C11 belongs only to
the overriding SE Asian plate (figure 9(c)). Cluster C12 is located below the West
Sunda Trench (figure 9(d)).
The present understanding on subduction kinematics for this complex arc can be
improved only when a comparison of results of clustering analysis with more
homogeneous data sets becomes available with a combination of greater
Figure 9. (a) Clusters C10–C13 in offshore Sumatra. This is by far the largest cluster found for
the study area and is also seismically the deadliest. Other symbols are as in figure 6. Mostly
thrust mechanisms prevail in the region of all four clusters, where P–T axes are orientated
NE–SW. A summary plot for focal mechanism stress axes is shown in the inset. Seismological
depth sections: (b) across C10 and summary plot for focal mechanism stress axes; (c) across
C11; (d) across C12; and (e) seismologic section across cluster C13 of WSA, and summary plot
for focal mechanism stress axes. Note the coupling between the lower and upper plates in the
C10 and C13 clusters. OAR: Outer Arc Ridge; SFS: Semangko Fault system; T: Andaman
Trench; VA: Volcanic Arc; WAF: West Andaman Fault.
instrumental data coverage, in particular, for smaller magnitude earthquakes. A

temporary digital network established on the Andaman Islands by the Geological
Survey of India recorded about 18,000 small aftershocks in about 10 weeks following
the 26 December 2004 Sumatra earthquake; the recorded magnitude is 3.0 and above
(Mishra et al. 2007).
4. Stress distributions and strain partitioning within seismic clusters

The Indian plate moves in a N108 E to N178 E direction between latitude 28 N (958 E
longitude) and 48 N (938 E) at rates of 52 mm and 61 mm per year, respectively,
beneath the Sunda Plate (Sieh and Natawidjaja 2000). The motion changes its
orientation to N238 E at 98 N latitude (928 E longitude) at a rate of about 54 mm
per year (DeMets et al. 1990). GPS data also indicate a non-negligible east–west
convergence along the Andaman arc (Paul et al. 2001). Such differential movement
vectors making a small angle to the trench axis in this oblique deformation front are
partitioned between two stress components, one parallel to the trench and the other
perpendicular to it. The trench parallel motion has been consumed along a large-
scale crustal structure with a dominant strike-slip motion (WAF, SFS and Shan-
Sagaing fault) parallel to the trench along fore-arc and also by back-arc spreading in
ASR by leaky transform tectonics. The trench perpendicular component generates
large-scale thrust-related motions in segments along the fore-arc (Eastern Boundary
Thrust; gap between the Andaman trench and WAF, etc.).
The stress distribution and strain partitioning along different sectors have been
studied in details on map and in depth sections across the clusters. Tectonic analyses
of clusters are carried out with the help of composite CMT plots generated from 518
well-constrained CMT solutions collected from the HRVD website. The zone from
north Burma to Sumatra has been associated with both positive and negative slips;
the positive slip is accommodated primarily by thrust motion, whereas the negative
slip is by normal fault or oblique slip movements. The pure strike–slip motion is in
between positive and negative slips. The composite CMT plots are constructed for
the clusters (figures 6–9) distributed along the entire length of the Burmese–
Andaman arc to illustrate the variation in stress axes and orientation of causative
fault planes. By composite CMT plot, here we mean that all the P, T axes and pole of
nodal planes of the earthquakes belonging to one cluster/multiple clusters (as the
case may be) are plotted on a stereographic projection for tectonic analysis,
irrespective of their type of fault plane solutions.
4.1 Burmese Arc Clusters: C1–C3

CMT solutions corresponding to all three clusters found for the Burmese Arc are
listed in table 3. This is a thrust-dominated domain, with subordinate strike-slip
movements. Cluster C1 is a shallow focus thrust–strike-slip domain in the overriding
Burma plate; C2 is an intermediate focus (4100 km) thrust-dominated domain with
occasional strike–slip earthquakes along the plate interface/subducting Indian Plate.
Similarly, C3 indicates a predominantly thrust domain in the subducting Indian
Plate. It can also be seen that the strike-slip earthquakes within this predominantly
thrust domain occur along the terminal ends of the elliptical cluster boundary. These
strike slip earthquakes occur due to the movement of adjacent cross-cutting hinge
faults, inferred by Dasgupta et al. (2003). Thus, the three clusters in between EBT
and the volcanic arc indicate earthquake concentration predominantly along the
plate interface or within plate. The CMT solution shows an overall NE–SW
compression at a shallow angle (108) and a NW–SE extension at a moderately high
angle (568) along this sector (table 4). The CMT data clearly show a dominance of
thrust movement in the C2–C3 clusters with subordinate strike-slip motion both
occurring even beyond a depth of 100 km; this was indicated previously by Stork
et al. (2008) in the Burma subduction zone.
The right-lateral strike-slip motion in both the plates is consistent with the
geometry in Burmese arc and surrounding terrains in China where right-lateral
strike-slip movement predominates along N–S to NW–SE planes. The motion of
the Indian plate is primarily accommodated by the positive slips associated with
the thrust movement along EBT zones resulting in formation of C2 and C3
clusters. The counter motion on the overriding plate generates the cluster C1. The
residual slip adjustment takes place along the Shan-Sagaing fault that principally
accommodates a sizeable amount of the motion by aseismic slip/creep along its
length up to the Gulf of Martaban and may have contributed to the extension
along ASR.
4.2 Andaman Arc Clusters: C4–C8

Seismic clusters C4, C5 and C6 underlie the Andaman fore arc; they are thrust-
dominated clusters with normal fault events (figure 7(a)). These shallow focus thrust
14
Table 3. CMT solutions (source: http://www.seismology.harvard.edu) for 518 earthquakes for the Burmese–Andaman and West Sunda Arc system. The
solution parameters are discussed in text in relation to the seismic clusters. *Solution on the basis of Aki–Richards convention on slip. The value of first
column (No) is plotted on the maps (figures 5(a)–8(a)).
Plane 1 Plane 1 Plane 1 Plane 2 Plane 2 Plane 2
No Date h:min:s Latitude Longitude Depth Mw T_plunge T_azimuth N_plunge N_azimuth P_plunge P_azimuth Strike Dip slip Strike Dip slip Cluster Solution*
1 28/11/1984 10:29:29.5 26.52 96.96 16.0 5.7 38 162 47 16 18 267 311 49 17 210 77 138 C1 Strike-slip
2 7/6/2000 21:47:0.2 26.70 97.15 37.0 6.3 57 118 28 333 16 234 290 38 41 166 66 120 C1 Thrust
3 29/5/1979 0:39:55.7 24.92 95.05 108.5 5.4 60 120 20 250 21 348 109 30 134 241 69 68 C2 Thrust
4 23/8/1983 12:12:19 24.48 94.69 147.9 5.2 67 127 22 321 5 229 297 44 58 158 54 118 C2 Thrust
5 13/8/1988 19:59:52.7 24.94 95.24 126.0 5.1 73 98 12 325 12 232 307 35 69 152 58 104 C2 Thrust
6 9/1/1990 18:51:36.2 24.42 94.95 129.6 6.3 58 142 24 276 20 16 140 32 139 267 69 64 C2 Thrust
7 8/8/1994 21:8:36.6 24.76 94.97 145.6 6.1 68 129 16 266 14 0 111 34 120 257 61 71 C2 Thrust
8 6/5/1995 1:59:13.8 24.83 95.02 147.7 6.4 69 94 19 302 9 209 278 39 60 135 57 112 C2 Thrust
9 2/5/1998 8:36:54.6 24.84 95.09 127.4 5.5 32 92 58 271 0 2 132 68 156 232 68 24 C2 Strike-slip
10 2/7/2000 4:27:58 24.45 94.67 103.2 5.2 48 117 33 254 22 359 133 37 155 244 75 56 C2 Thrust
11 12/8/2001 1:58:0.9 24.43 94.99 142.0 5.1 62 112 26 320 12 224 285 40 48 155 61 119 C2 Thrust
12 15/2/2005 13:5:53.8 24.40 94.62 60.4 5.2 40 132 50 318 3 225 276 61 28 171 65 147 C2 Strike-slip
13 18/9/2005 7:26:1.7 24.48 94.71 105.4 5.7 50 121 40 308 3 215 271 54 38 156 60 138 C2 Strike-slip
14 1/5/1981 4:8:13 23.32 94.64 99.1 5.0 49 70 21 314 34 210 247 22 21 137 82 111 C3 Thrust
15 24/8/1987 9:24:44.4 23.04 94.53 126.5 5.3 54 119 33 270 14 9 135 42 144 254 67 54 C3 Thrust
16 11/10/2000 9:42:11.1 23.58 94.63 122.3 5.6 58 62 2 155 31 246 343 14 98 155 77 88 C3 Thrust
17 7/5/2007 5:58:36.7 23.02 94.58 97.3 5.0 24 90 66 285 5 183 229 69 13 134 77 159 C3 Strike-slip
18 7/12/2007 6:56:33 23.46 94.66 108.7 5.0 69 131 20 292 6 24 135 42 120 277 54 65 C3 Thrust
19 7/2/1978 12:30:48.2 12.98 93.19 15.0 5.6 60 321 28 164 10 69 129 43 46 2 61 123 C4 Thrust
20 7/2/1978 20:32:1 12.83 93.03 15.0 5.7 81 230 3 338 9 68 162 36 95 336 54 86 C4 Thrust
21 20/9/1986 10:4:58.7 12.82 93.16 21.6 5.1 62 114 12 1 25 266 332 23 59 185 71 102 C4 Thrust
22 20/11/2003 00:14:5:4 13.21 93.07 39.2 5.4 66 173 21 22 11 288 354 39 55 216 59 115 C4 Thrust
23 6/3/2004 10:21:34.4 13.05 93.19 24.7 5.5 41 184 46 339 13 82 214 52 157 319 72 41 C4 Strike-slip
24 10/4/2004 15:57:4 13.19 93.09 33.4 5.1 72 129 8 14 16 281 359 30 73 198 62 99 C4 Thrust
B. Mukhopadhyay et al.
25 3/5/2004 17:41:32.5 13.18 93.19 27.8 5.2 72 151 12 20 13 287 1 34 68 207 59 104 C4 Thrust
26 29/1/2005 5:44:13.6 13.18 93.07 20.6 5.2 58 314 30 155 9 59 118 44 44 353 61 125 C4 Thrust
27 30/1/2005 7:2:25.1 13.20 92.97 23.1 5.1 24 324 65 158 5 56 103 69 14 8 77 158 C4 Strike-slip
28 21/1/2006 4:7:7 13.10 93.23 39.0 5.7 72 77 6 187 17 279 19 29 103 184 62 83 C4 Thrust
29 27/12/2004 14:46:48.6 12.39 92.72 27.0 5.6 28 81 8 346 61 242 191 19 764 344 73 798 C5 Normal
30 4/1/2005 9:13:17.4 10.65 92.03 24.0 6.0 64 68 6 170 25 263 5 20 107 168 70 84 C6 Thrust
31 28/12/2004 10:51:50.6 10.61 92.20 12.0 5.3 51 66 5 162 39 257 22 8 130 162 84 85 C6 Thrust
32 28/12/2004 23:40:2.1 11.12 92.04 12.0 5.0 6 276 29 9 61 174 337 46 7132 209 57 755 C6 Normal
33 31/12/2004 5:53:57 11.15 91.98 12.5 5.1 13 316 40 57 47 212 7 48 7151 256 69 746 C6 Normal
34 1/1/2005 11:53:14.1 11.14 91.67 21.6 5.0 9 287 13 19 74 162 1 37 7112 208 56 774 C6 Normal
35 6/1/2005 11:55:47.8 11.01 91.99 13.0 5.5 23 92 17 354 61 232 211 26 750 348 70 7108 C6 Normal
36 27/1/2005 5:51:4.4 10.72 91.72 37.3 5.2 77 7 13 188 0 98 175 46 72 20 47 108 C6 Thrust
37 22/2/2005 17:12:1.5 10.81 91.72 12.0 5.5 70 121 10 3 18 270 345 29 69 188 63 101 C6 Thrust
38 10/4/2005 2:23:51.4 10.75 92.09 12.0 5.0 52 78 11 182 36 280 56 13 144 181 82 79 C6 Thrust
39 22/12/2006 19:50:49 10.70 92.11 22.0 6.2 59 73 1 165 31 255 350 14 95 164 76 89 C6 Thrust
40 29/8/2005 14:44:48.8 11.04 91.92 21.0 5.2 60 100 7 357 28 263 334 18 66 179 74 97 C6 Thrust
(continued)
Table 3. (Continued).
41 11/10/2005 3:38:0.9 10.89 92.02 24.0 5.3 66 71 4 171 23 263 1 22 101 169 68 86 C6 Thrust
42 5/2/2006 13:40:35.8 11.03 91.75 15.8 4.8 10 277 6 8 79 129 359 36 7100 192 55 783 C6 Normal
43 9/6/1991 20:39:36.5 12.70 95.14 40.6 5.5 2 332 87 116 2 242 17 87 180 107 90 3 C7 Strike-slip
44 19/3/1993 15:53:57.6 12.62 95.75 15.0 5.3 0 129 30 219 60 38 192 52 7129 65 52 751 C7 Normal
45 13/1/2003 16:35:1.9 12.93 95.65 15.0 5.3 25 332 52 100 26 229 11 52 7180 281 90 738 C7 Strike-slip
46 26/1/2003 10:49:30.4 12.98 95.36 26.0 5.1 34 97 32 342 40 220 245 32 76 340 87 7122 C7 Normal
47 19/7/1984 16:16:10.6 11.11 94.58 25.1 4.8 2 344 23 253 67 79 96 47 758 233 52 7120 C8 Normal
48 10/3/2006 4:5:44.3 10.73 94.37 12.0 5.5 11 338 2 69 79 170 66 34 794 250 56 787 C8 Normal
49 10/3/2006 4:43:35.4 10.64 94.35 12.0 5.2 11 330 1 60 79 155 59 34 792 241 56 789 C8 Normal
50 10/3/2006 5:6:12 10.69 94.41 12.0 5.1 15 333 16 67 68 200 41 33 7120 255 62 772 C8 Normal
51 10/3/2006 12:4:0.3 10.79 94.53 12.0 5.2 16 344 3 75 73 174 70 29 796 256 61 787 C8 Normal
52 11/3/2006 11:48:53.1 10.69 94.40 12.0 5.1 1 321 11 52 79 225 40 45 7106 242 47 774 C8 Normal
53 16/3/2006 13:59:23.8 10.75 94.45 12.0 5.5 11 342 0 72 79 164 71 34 791 252 56 790 C8 Normal
54 19/3/2006 19:12:16.2 10.78 94.52 12.0 4.9 12 344 3 253 77 148 78 33 784 251 57 794 C8 Normal
55 19/3/2006 21:57:16.6 10.77 94.46 12.0 5.0 11 349 6 258 78 142 86 35 780 254 56 797 C8 Normal
56 9/8/1994 23:35:1.7 10.57 94.34 33.0 5.5 28 339 11 243 60 133 96 20 755 239 74 7102 C8 Normal
57 10/8/1994 1:39:29.7 10.96 94.35 15.0 5.4 0 142 2 52 88 232 234 45 787 49 45 793 C8 Normal
58 9/3/2006 14:48:56.8 10.79 94.48 12.0 4.9 12 343 10 251 74 124 85 34 773 245 58 7101 C8 Normal
59 9/3/2006 14:57:12.4 10.80 94.14 12.0 5.1 40 291 6 196 50 99 63 8 743 196 85 796 C8 Normal
60 9/3/2006 15:3:16 10.87 94.55 17.1 5.1 10 340 9 72 76 203 58 36 7106 258 56 779 C8 Normal
61 9/3/2006 15:12:4.4 10.78 94.51 12.0 5.2 13 337 17 243 68 101 89 36 759 232 60 7110 C8 Normal
62 9/3/2006 15:19:18.6 10.89 94.68 12.0 5.2 14 344 10 76 73 199 60 32 7108 262 60 779 C8 Normal
63 9/3/2006 15:46:58.6 10.81 94.49 12.0 5.0 11 347 5 256 78 140 83 35 781 252 56 796 C8 Normal
64 9/3/2006 16:42:37.4 10.73 94.48 21.4 5.0 2 347 4 77 86 230 74 43 795 261 47 785 C8 Normal
65 9/3/2006 17:9:10.1 10.83 94.47 18.2 5.0 10 331 6 240 78 118 69 36 779 235 55 798 C8 Normal
66 9/3/2006 18:21:55.4 10.82 94.69 12.0 5.4 6 347 4 257 83 137 81 39 784 254 52 795 C8 Normal
67 9/3/2006 18:26:33.1 10.79 94.51 12.0 5.3 25 344 20 244 57 121 111 27 740 238 73 7111 C8 Normal
68 9/3/2006 19:15:46 10.79 94.55 12.1 5.2 6 346 4 77 83 199 72 39 796 260 51 785 C8 Normal
69 9/3/2006 20:25:47.7 10.79 94.52 12.0 5.2 20 347 10 80 67 195 60 26 7113 265 66 779 C8 Normal
70 9/3/2006 21:18:57.7 10.86 94.66 12.0 5.0 15 344 4 253 75 148 79 31 782 250 60 794 C8 Normal
71 9/3/2006 21:37:2.4 10.76 94.49 12.0 5.3 10 346 7 77 77 203 67 36 7103 263 56 781 C8 Normal
72 9/3/2006 22:30:49 10.75 94.46 12.0 5.3 13 346 0 255 77 164 76 32 790 255 58 790 C8 Normal
73 10/3/2006 1:13:43.8 10.72 94.67 18.1 4.9 20 156 12 61 67 302 266 28 763 56 66 7103 C8 Normal
74 8/6/1979 20:36:41.4 7.47 94.14 124.3 5.1 58 163 3 68 32 336 55 13 77 249 77 93 C9 Thrust
75 8/4/1982 21:34:19 7.40 94.10 33.0 5.3 8 306 79 170 8 37 81 79 0 351 90 169 C9 Strike-slip
76 22/5/1982 8:53:4.8 7.61 94.39 12.2 5.5 23 296 3 27 67 125 19 23 798 208 68 786 C9 Normal
77 28/1/1986 12:32:18.6 8.81 94.01 15.0 6.0 2 301 86 55 4 211 346 86 7178 256 88 74 C9 Strike-slip
78 19/6/1986 18:12:32.8 7.90 94.40 181.3 5.9 23 204 18 302 60 66 263 27 7132 128 70 771 C9 Normal
79 19/2/1989 1:46:1.6 7.65 94.47 15.0 5.3 17 95 57 212 27 356 138 58 7172 43 83 732 C9 Strike-slip
80 30/4/1990 18:0:25.6 8.05 94.50 15.0 5.6 10 288 73 55 13 195 332 73 7178 241 88 717 C9 Strike-slip
81 18/8/1990 18:52:43.3 7.75 93.86 15.0 6.0 12 141 73 275 11 48 185 73 180 275 90 17 C9 Strike-slip
Seismic cluster analysis for the Burmese–Andaman and West Sunda Arc
82 29/12/1990 13:23:55.2 8.14 93.93 21.0 6.1 3 302 86 90 2 212 347 86 179 77 89 4 C9 Strike-slip
(continued)
15
16
83 18/7/1991 9:50:41.6 8.37 94.29 41.9 5.5 3 297 87 137 1 28 73 87 1 342 89 177 C9 Strike-slip
84 26/8/1991 20:54:25.4 7.30 94.54 49.6 5.9 5 281 67 24 22 189 327 71 7168 233 78 720 C9 Strike-slip
85 4/1/2005 12:15:36 8.83 93.64 12.0 4.9 26 127 7 221 62 325 199 20 7112 43 72 782 C9 Normal
86 25/5/1994 18:42:23.6 7.70 94.37 41.4 5.9 6 103 84 272 1 13 148 85 177 238 87 5 C9 Strike-slip
87 27/7/1995 15:16:32.8 9.18 93.97 26.7 5.2 4 145 54 241 36 52 195 62 7156 93 69 730 C9 Strike-slip
88 13/4/1996 10:45:22.4 7.28 94.57 48.1 5.4 2 101 87 223 3 11 146 87 7179 56 89 73 C9 Strike-slip
89 25/6/1996 7:28:59.1 8.65 93.87 29.9 5.2 6 306 83 140 2 37 82 84 3 351 87 174 C9 Strike-slip
90 12/1/1998 22:40:2.3 9.38 93.63 110.8 5.4 42 75 48 252 2 344 111 60 149 218 64 33 C9 Strike-slip
91 9/8/1998 0:34:58.2 7.43 94.42 28.0 5.4 12 104 77 291 1 195 240 80 8 149 82 170 C9 Strike-slip
92 10/8/1998 9:52:17.5 7.58 94.39 23.7 5.9 5 102 84 326 4 192 237 84 0 147 90 174 C9 Strike-slip
93 15/10/1998 19:5:26.6 7.73 94.34 52.1 5.4 8 112 78 244 8 21 156 78 7180 66 90 712 C9 Strike-slip
94 29/8/1999 3:44:51.6 8.88 93.52 24.8 5.2 31 151 55 301 14 52 187 58 167 285 79 33 C9 Strike-slip
95 18/12/1999 0:50:33.5 7.05 94.56 25.0 5.2 13 278 67 156 19 12 54 67 75 146 85 7157 C9 Strike-slip
96 15/3/2001 0:39:11 8.76 94.08 28.3 5.4 5 115 81 355 8 206 250 81 72 341 88 7171 C9 Strike-slip
97 15/3/2001 1:22:44.3 8.79 94.11 29.9 6.0 5 303 81 65 8 213 348 81 7178 258 88 79 C9 Strike-slip
98 17/1/2003 14:31:12.7 8.00 93.89 17.1 5.2 9 135 69 20 19 229 271 70 77 3 84 7160 C9 Strike-slip
99 30/1/2003 17:21:9.4 7.80 94.32 37.1 5.2 1 102 83 6 7 192 237 85 75 327 85 7174 C9 Strike-slip
100 15/4/2004 21:20:42 8.80 94.10 18.6 5.3 12 113 78 285 2 23 157 80 173 249 83 10 C9 Strike-slip
101 15/4/2004 23:2:15 8.85 94.15 17.6 5.0 21 117 36 223 47 3 163 40 7156 54 75 753 C9 Normal
102 16/4/2004 2:6:15.3 8.88 94.14 21.1 5.6 4 110 76 218 13 19 156 78 7174 64 84 712 C9 Strike-slip
103 16/4/2004 11:29:48.7 8.90 94.05 22.5 4.8 15 106 72 251 10 13 149 72 176 240 86 18 C9 Strike-slip
104 18/5/2004 2:58:18.7 7.40 93.81 73.3 5.0 20 87 70 267 0 177 223 76 14 130 76 165 C9 Strike-slip
105 26/12/2004 10:18:14.6 8.91 94.11 33.3 6.4 72 279 16 73 7 165 272 40 115 61 54 70 C9 Thrust
106 27/12/2004 0:39:46.9 8.98 93.69 15.8 5.4 3 105 22 196 68 6 173 46 7121 34 52 762 C9 Normal
107 11/1/2005 5:49:31.6 8.16 93.85 12.9 4.9 5 307 18 39 71 202 19 43 7117 233 53 767 C9 Normal
108 27/12/2004 2:4:25.6 8.07 94.29 12.0 5.2 27 86 29 339 48 211 223 32 723 333 78 7120 C9 Normal
109 27/12/2004 14:30:36.3 8.63 93.90 12.0 5.2 25 79 31 333 48 201 215 34 723 325 77 7122 C9 Normal
110 27/12/2004 19:28:53.3 8.72 93.93 12.0 5.3 21 78 5 346 68 245 177 24 779 344 66 795 C9 Normal
111 27/12/2004 20:36:19.8 8.93 93.80 12.0 5.3 15 83 4 352 74 249 178 30 783 350 60 794 C9 Normal
112 28/12/2004 0:37:53.5 7.61 94.32 22.0 5.5 1 97 80 193 10 7 143 82 7174 52 84 78 C9 Strike-slip
113 28/12/2004 5:36:14.3 9.48 93.77 12.0 5.4 9 98 9 7 77 232 199 37 774 0 55 7101 C9 Normal
114 28/12/2004 19:55:12.9 9.44 93.76 12.0 5.2 8 99 8 8 78 231 199 38 776 1 54 7101 C9 Normal
115 28/12/2004 21:47:33 9.06 93.78 12.0 5.4 14 87 23 351 62 205 205 37 749 338 63 7116 C9 Normal
116 29/12/2004 1:50:57.7 9.12 93.97 12.0 6.0 11 99 28 4 60 208 220 42 746 347 61 7122 C9 Normal
117 29/12/2004 6:19:7 9.55 93.90 12.0 5.4 18 99 14 4 67 239 210 30 761 358 64 7105 C9 Normal
118 29/12/2004 10:9:23.8 7.61 93.81 12.0 5.0 3 339 22 70 67 242 47 46 7122 269 52 761 C9 Normal
119 29/12/2004 22:55:44.6 7.67 93.78 19.6 4.8 1 348 1 258 89 117 79 44 789 257 46 791 C9 Normal
120 31/12/2004 9:57:4.2 7.62 94.00 12.0 5.6 6 297 30 30 59 197 358 47 7133 232 58 753 C9 Normal
121 31/12/2004 16:15:47.7 7.56 93.99 12.0 4.9 8 109 1 199 82 297 197 37 792 20 53 789 C9 Normal
122 1/1/2005 1:42:23.8 7.24 93.96 12.0 5.0 16 149 43 44 43 254 282 48 723 28 73 7136 C9 Strike-slip
123 1/1/2005 19:8:5.8 7.15 94.49 19.8 6.1 0 290 72 199 18 20 63 77 713 156 78 7167 C9 Strike-slip
124 7/1/2005 10:49:15.2 8.89 93.61 12.0 5.3 1 108 21 17 69 200 218 48 761 358 50 7119 C9 Normal
(continued)
125 18/1/2005 22:4:46.7 8.34 93.97 26.1 4.9 1 128 80 222 10 38 173 82 7173 82 83 78 C9 Strike-slip
126 26/1/2005 17:30:30.4 8.20 94.14 12.0 5.6 1 117 63 209 27 27 165 71 7161 69 72 720 C9 Strike-slip
127 26/1/2005 22:47:0.6 7.92 94.14 21.4 5.5 14 114 70 246 14 20 157 70 7180 67 90 720 C9 Strike-slip
128 26/1/2005 23:3:8.6 7.94 94.23 14.6 5.1 22 111 32 215 49 353 158 37 7153 46 74 756 C9 Normal
129 27/1/2005 3:58:45.6 7.94 94.20 19.5 5.4 16 111 64 236 21 15 154 64 7176 62 87 726 C9 Strike-slip
130 27/1/2005 4:2:50.1 7.89 94.21 12.7 5.1 27 106 49 233 28 1 144 49 7179 53 89 741 C9 Strike-slip
131 27/1/2005 5:22:20.3 7.90 94.18 19.7 5.4 13 111 65 231 21 16 155 65 7174 62 85 725 C9 Strike-slip
132 27/1/2005 5:48:12.9 7.99 94.20 14.9 5.3 27 112 48 236 30 6 150 48 7177 58 88 742 C9 Strike-slip
133 27/1/2005 6:14:31 7.94 94.18 12.0 5.0 21 100 34 205 49 345 148 39 7153 36 74 754 C9 Normal
134 27/1/2005 6:56:58.6 7.92 94.17 18.5 5.6 2 120 75 219 15 30 166 78 7171 74 81 712 C9 Strike-slip
135 27/1/2005 7:20:26.4 7.95 94.19 14.0 5.2 21 114 38 221 45 2 159 41 7158 52 75 751 C9 Normal
136 27/1/2005 7:26:1.8 7.99 94.21 21.6 5.3 21 112 62 248 18 15 153 62 178 244 88 28 C9 Strike-slip
137 27/1/2005 7:28:32.2 7.98 94.22 22.9 5.2 3 311 38 43 52 218 9 54 7139 252 58 744 C9 Strike-slip
138 27/1/2005 7:35:46.9 7.96 94.20 17.0 5.2 11 124 75 346 9 216 260 76 1 170 89 166 C9 Strike-slip
139 27/1/2005 7:41:26.2 7.90 94.25 22.2 4.9 19 100 58 223 25 1 142 58 7175 50 86 732 C9 Strike-slip
140 27/1/2005 8:7:26.3 7.93 94.20 14.2 5.2 14 125 51 234 35 25 170 55 7164 71 77 737 C9 Strike-slip
141 27/1/2005 8:19:9.1 7.93 94.17 12.0 5.5 3 124 83 239 7 33 168 83 7178 78 88 77 C9 Strike-slip
142 27/1/2005 8:31:12.1 7.96 94.22 14.6 5.3 12 95 75 235 9 3 138 75 178 229 88 15 C9 Strike-slip
143 27/1/2005 8:36:52 7.89 94.21 16.5 5.2 29 125 35 238 41 6 162 36 7169 63 83 755 C9 Normal
144 27/1/2005 8:42:16.1 7.83 94.22 14.8 5.5 24 106 51 229 29 1 145 51 7176 53 87 739 C9 Strike-slip
145 27/1/2005 9:11:28.8 8.11 94.26 16.1 5.2 17 108 37 5 48 218 240 43 727 350 72 7129 C9 Normal
146 27/1/2005 9:25:28.7 7.94 94.16 17.7 5.2 16 129 60 251 24 32 172 61 7174 79 85 729 C9 Strike-slip
147 27/1/2005 9:52:21.3 7.87 94.25 20.0 5.4 19 102 65 241 15 7 144 65 177 235 87 25 C9 Strike-slip
148 27/1/2005 9:59:31.8 7.98 94.22 25.2 5.3 12 125 65 243 22 30 169 66 7173 76 84 725 C9 Strike-slip
149 27/1/2005 10:8:13.5 7.92 94.16 19.5 5.3 14 117 50 224 36 16 163 54 7162 62 76 737 C9 Strike-slip
150 27/1/2005 10:25:53.7 7.99 94.26 12.0 5.1 26 102 41 217 38 349 141 42 7169 43 83 749 C9 Normal
151 27/1/2005 10:58:7.5 7.91 94.11 13.9 5.3 0 129 90 295 0 39 174 90 180 264 90 0 C9 Strike-slip
152 27/1/2005 11:44:6.3 8.02 94.15 12.0 5.3 4 118 48 23 42 212 246 58 729 353 65 7145 C9 Strike-slip
153 27/1/2005 11:47:36.9 7.92 94.20 12.0 5.5 3 301 86 160 2 31 76 86 0 346 90 176 C9 Strike-slip
154 27/1/2005 11:56:43.5 7.88 94.16 15.5 5.1 16 127 30 226 55 12 181 39 7143 60 67 757 C9 Normal
155 27/1/2005 12:11:55.3 7.98 94.28 12.0 5.4 4 139 86 295 2 49 184 86 178 274 88 4 C9 Strike-slip
156 27/1/2005 13:15:20.4 7.86 94.14 17.1 5.4 18 110 61 235 22 12 152 61 7177 60 87 729 C9 Strike-slip
157 27/1/2005 13:18:5.7 7.92 94.25 23.3 5.3 15 104 61 223 24 8 148 62 7173 55 84 728 C9 Strike-slip
158 27/1/2005 13:25:21.6 7.77 94.20 18.1 5.2 16 108 69 245 13 14 150 69 178 241 88 21 C9 Strike-slip
159 27/1/2005 13:26:33.6 7.84 94.24 22.2 5.3 18 112 67 252 14 18 154 67 177 245 87 23 C9 Strike-slip
160 27/1/2005 13:54:15.4 7.92 94.17 19.5 5.4 5 121 79 240 10 30 166 79 7177 76 87 711 C9 Strike-slip
161 27/1/2005 13:57:7.2 7.97 94.16 16.3 5.5 9 110 65 221 23 16 155 67 7170 62 81 723 C9 Strike-slip
162 27/1/2005 14:13:18 7.95 94.14 17.3 5.1 22 107 30 211 51 347 155 35 7151 41 74 758 C9 Normal
163 27/1/2005 14:35:9.2 7.95 94.20 22.3 5.1 16 117 61 239 23 20 160 62 7175 67 85 728 C9 Strike-slip
164 27/1/2005 15:24:51.5 7.66 94.21 24.7 5.2 23 129 50 8 31 233 268 51 76 2 85 7140 C9 Strike-slip
165 27/1/2005 15:27:53.8 7.94 94.16 12.0 5.3 11 129 57 22 31 226 263 61 715 1 77 7150 C9 Strike-slip
166 27/1/2005 15:34:30.4 7.74 94.25 23.0 5.3 11 113 45 215 43 13 163 52 7154 56 70 741 C9 Strike-slip
(continued)
17
18
167 27/1/2005 16:0:57.9 7.76 94.18 32.5 5.0 31 123 59 294 4 31 162 66 160 261 72 25 C9 Strike-slip
168 27/1/2005 16:2:22.3 8.04 94.25 31.6 5.1 5 126 77 237 12 35 171 78 7175 80 85 712 C9 Strike-slip
169 27/1/2005 16:48:28.5 7.94 94.14 12.0 5.0 4 306 81 187 8 37 81 82 72 171 88 7172 C9 Strike-slip
170 27/1/2005 16:58:52.3 7.81 94.24 19.5 5.8 4 104 77 212 12 13 149 78 7174 58 84 712 C9 Strike-slip
171 27/1/2005 17:25:1.9 7.78 94.25 19.0 5.4 20 115 62 250 18 18 156 62 178 247 88 28 C9 Strike-slip
172 27/1/2005 17:40:49.5 7.92 94.17 13.0 5.4 13 121 20 216 66 360 187 36 7125 48 61 767 C9 Normal
173 27/1/2005 18:52:39.3 7.85 94.24 15.9 5.6 13 102 64 220 22 7 146 65 7173 53 84 725 C9 Strike-slip
174 27/1/2005 19:20:21.9 7.91 94.17 12.0 5.3 8 123 23 216 66 16 189 42 7125 52 56 763 C9 Normal
175 27/1/2005 19:31:11.1 8.00 94.20 19.3 5.2 13 115 42 216 45 12 165 49 7152 56 69 745 C9 Normal
176 27/1/2005 19:40:39.5 8.16 94.07 15.3 5.3 13 133 17 227 68 9 202 36 7121 58 60 770 C9 Normal
177 27/1/2005 20:17:39.2 8.01 94.19 22.6 5.1 13 114 55 223 32 16 159 58 7165 62 78 733 C9 Strike-slip
178 27/1/2005 20:31:2.8 7.97 94.19 16.3 5.2 19 120 36 224 48 7 167 41 7153 57 73 752 C9 Normal
179 27/1/2005 20:45:20.1 7.89 94.19 15.1 5.0 24 137 20 236 58 1 191 27 7138 63 72 769 C9 Normal
180 27/1/2005 20:51:10.9 8.11 94.18 16.6 5.2 0 138 78 231 12 48 184 81 7172 93 82 79 C9 Strike-slip
181 27/1/2005 21:5:5.3 7.99 94.26 15.4 5.1 25 86 49 208 30 340 125 49 7176 32 87 741 C9 Strike-slip
182 27/1/2005 21:32:20 7.98 94.17 17.0 5.2 13 108 53 215 34 9 154 57 7163 54 76 734 C9 Strike-slip
183 27/1/2005 21:47:56.1 7.95 94.17 12.0 5.2 18 121 0 211 72 301 211 27 790 31 63 790 C9 Normal
184 27/1/2005 22:40:48.4 8.00 94.18 12.0 5.4 5 122 23 30 66 223 235 45 756 12 54 7119 C9 Normal
185 27/1/2005 22:56:51.4 8.05 94.31 21.9 5.0 16 117 32 217 54 4 170 40 7145 52 68 756 C9 Normal
186 27/1/2005 23:20:9.1 8.02 94.20 12.0 5.4 15 110 49 218 36 8 155 53 7163 54 77 739 C9 Strike-slip
187 27/1/2005 23:27:3.2 7.89 94.23 22.8 5.1 35 106 54 268 9 10 142 60 160 243 73 32 C9 Strike-slip
188 27/1/2005 23:40:49.5 8.00 94.25 21.6 4.9 8 108 34 204 55 7 166 47 7139 45 61 751 C9 Normal
189 28/1/2005 0:15:46.5 7.84 94.21 17.6 5.3 16 111 62 233 23 14 154 62 7175 62 85 728 C9 Strike-slip
190 28/1/2005 1:1:29.6 7.94 94.17 12.0 4.9 6 128 19 221 70 22 198 42 7119 55 54 766 C9 Normal
191 28/1/2005 1:36:20.2 7.96 94.23 12.0 5.2 18 123 6 215 71 322 204 27 7102 38 63 784 C9 Normal
192 28/1/2005 1:43:39.8 7.96 94.23 28.2 5.0 9 117 4 208 80 325 202 37 797 31 54 785 C9 Normal
193 28/1/2005 2:23:15.6 7.87 94.20 15.5 5.3 18 100 46 210 38 355 144 48 7163 43 78 743 C9 Strike-slip
194 28/1/2005 2:28:58.3 7.99 94.15 12.0 5.2 15 117 29 18 56 231 241 39 739 4 66 7122 C9 Normal
195 28/1/2005 3:31:26.9 8.06 94.20 12.0 5.4 1 123 35 33 55 215 244 54 745 4 56 7134 C9 Normal
196 28/1/2005 4:34:41.6 7.89 94.23 17.6 5.2 29 128 53 265 21 26 164 54 174 258 85 37 C9 Strike-slip
197 28/1/2005 5:4:34.6 7.88 94.18 12.0 5.4 15 100 59 215 27 2 144 60 7170 49 82 730 C9 Strike-slip
198 28/1/2005 5:38:27.1 7.82 94.20 17.4 5.1 20 106 48 220 35 2 149 50 7168 51 81 741 C9 Strike-slip
199 28/1/2005 6:6:55.5 7.73 94.21 16.8 5.4 0 262 52 172 38 353 31 64 729 134 65 7151 C9 Strike-slip
200 28/1/2005 6:10:30.1 7.85 94.17 12.0 5.5 15 99 59 215 27 2 143 60 7171 49 82 730 C9 Strike-slip
201 28/1/2005 6:13:27.6 7.79 94.16 17.8 5.7 9 106 64 215 24 12 152 66 7168 57 79 724 C9 Strike-slip
202 28/1/2005 7:49:17.5 7.82 94.23 16.0 5.6 13 98 58 210 29 1 143 60 7168 47 80 730 C9 Strike-slip
203 28/1/2005 8:21:23.9 8.01 94.17 12.0 5.3 9 121 5 30 80 270 217 37 782 27 54 796 C9 Normal
204 28/1/2005 8:29:47.2 7.82 94.27 18.4 5.3 20 102 41 211 42 353 147 44 7161 43 77 748 C9 Normal
205 28/1/2005 8:47:18.7 7.84 94.11 13.1 5.3 23 103 55 228 26 1 143 55 7177 51 88 735 C9 Strike-slip
206 28/1/2005 9:14:46.4 8.00 94.21 22.0 5.2 17 118 63 244 20 21 160 63 7177 69 88 727 C9 Strike-slip
207 28/1/2005 10:21:20.5 7.66 93.91 19.4 5.2 17 277 31 176 53 31 45 39 734 163 69 7124 C9 Normal
208 28/1/2005 11:53:3.7 7.84 94.23 17.2 5.3 10 100 65 212 23 5 145 67 7170 51 81 724 C9 Strike-slip
(continued)
209 28/1/2005 12:37:13.2 8.07 94.22 12.0 5.1 5 122 21 30 69 225 233 44 760 14 53 7116 C9 Normal
210 28/1/2005 17:49:41.5 8.12 94.30 12.0 5.1 15 113 11 20 71 256 219 31 768 14 61 7103 C9 Normal
211 28/1/2005 19:18:54.6 7.86 94.20 12.0 5.5 12 98 59 208 28 1 143 61 7167 47 79 729 C9 Strike-slip
212 28/1/2005 22:29:4.4 7.75 94.23 20.6 5.4 17 113 68 253 13 19 155 68 177 246 87 22 C9 Strike-slip
213 28/1/2005 22:35:29.5 7.71 94.01 15.3 5.2 18 109 17 13 65 242 224 31 755 5 65 7109 C9 Normal
214 28/1/2005 23:32:11.8 8.05 94.24 12.0 5.0 7 119 17 27 71 229 228 41 763 14 54 7112 C9 Normal
215 29/1/2005 1:50:22.1 7.77 94.23 21.3 5.4 4 114 80 227 9 23 159 81 7176 68 86 79 C9 Strike-slip
216 29/1/2005 3:38:3.6 8.09 94.25 12.0 5.1 10 117 19 24 68 233 229 39 759 11 58 7113 C9 Normal
217 29/1/2005 5:26:48.8 7.82 94.20 12.0 5.3 15 99 63 221 22 3 142 64 7175 50 85 726 C9 Strike-slip
218 29/1/2005 9:27:40.1 7.76 94.29 15.4 5.0 22 108 51 229 30 4 148 52 7174 54 85 738 C9 Strike-slip
219 29/1/2005 16:12:50.9 8.18 94.25 25.4 5.0 17 109 61 231 23 11 151 61 7175 59 86 729 C9 Strike-slip
220 29/1/2005 16:36:55.6 8.05 94.26 12.0 5.1 13 113 15 19 70 242 222 35 763 10 60 7108 C9 Normal
221 29/1/2005 18:37:58.4 8.11 94.33 15.6 4.9 4 119 28 27 62 217 236 48 751 5 55 7125 C9 Normal
222 29/1/2005 19:6:16.5 7.72 94.29 15.1 5.3 14 90 61 206 25 353 134 62 7171 40 82 728 C9 Strike-slip
223 29/1/2005 20:1:57.7 8.10 94.22 12.0 5.3 2 117 42 26 48 209 242 57 737 354 60 7141 C9 Strike-slip
224 29/1/2005 20:28:24.5 7.75 94.21 19.0 5.6 6 109 74 220 15 18 154 75 7174 63 84 715 C9 Strike-slip
225 29/1/2005 20:54:26 7.82 94.20 12.4 5.0 30 107 31 217 45 342 145 32 7164 42 82 759 C9 Normal
226 29/1/2005 20:58:34.6 8.01 94.19 12.0 5.0 17 126 3 217 73 316 211 28 796 38 62 787 C9 Normal
227 29/1/2005 22:3:52.6 7.80 94.18 12.0 5.4 7 100 64 204 25 6 146 67 7167 51 78 723 C9 Strike-slip
228 30/1/2005 0:7:35 8.13 94.21 19.7 5.3 1 130 75 223 15 39 176 79 7170 84 80 711 C9 Strike-slip
229 30/1/2005 0:34:11.4 8.07 94.21 13.6 5.1 5 125 32 31 57 223 245 49 745 8 58 7129 C9 Normal
230 30/1/2005 2:25:43.7 8.03 94.18 12.0 5.0 2 309 30 40 60 215 12 50 7130 245 54 752 C9 Normal
231 30/1/2005 2:35:17.8 8.06 94.23 12.0 5.2 2 309 51 41 39 218 1 62 7151 256 65 731 C9 Strike-slip
232 30/1/2005 3:13:38.1 8.06 94.25 19.1 5.1 7 124 83 292 1 33 168 84 176 259 86 6 C9 Strike-slip
233 30/1/2005 3:44:13.3 8.00 94.08 12.0 4.8 11 306 25 211 62 58 64 41 749 195 61 7119 C9 Normal
234 30/1/2005 8:49:39.5 7.94 94.18 12.0 5.2 5 135 28 227 62 35 198 47 7130 68 56 756 C9 Normal
235 30/1/2005 10:32:55.4 8.04 94.22 12.0 5.0 1 131 58 39 32 222 261 67 723 1 69 7155 C9 Strike-slip
236 30/1/2005 15:33:16.4 8.14 94.22 12.0 5.5 2 116 39 24 51 209 239 55 740 355 58 7137 C9 Strike-slip
237 30/1/2005 21:39:5.4 8.13 94.24 15.8 5.3 14 319 70 185 14 53 96 70 0 6 90 160 C9 Strike-slip
238 31/1/2005 2:20:43.8 8.02 94.23 18.5 4.8 4 152 25 60 64 250 267 47 754 40 54 7122 C9 Normal
239 31/1/2005 8:15:7.2 8.09 94.22 12.0 5.1 5 311 66 51 24 219 357 70 7166 262 77 721 C9 Strike-slip
240 31/1/2005 13:14:34.7 8.03 94.22 12.0 5.1 0 136 87 38 3 226 271 88 72 1 88 7178 C9 Strike-slip
241 31/1/2005 16:30:20.4 8.09 94.26 12.0 5.1 4 117 37 24 53 212 239 52 741 357 59 7134 C9 Normal
242 1/2/2005 1:8:3.4 7.81 94.21 12.0 5.3 13 100 58 212 29 3 145 60 7168 49 80 731 C9 Strike-slip
243 1/2/2005 13:41:55.8 8.08 94.22 12.0 5.2 7 315 20 47 69 206 24 42 7120 242 55 766 C9 Normal
244 2/2/2005 0:52:45.3 8.09 94.32 12.0 4.8 12 123 17 29 69 246 234 36 760 18 59 7110 C9 Normal
245 2/2/2005 13:22:38.5 8.09 94.27 12.0 5.1 2 314 86 185 3 44 89 86 0 179 90 7176 C9 Strike-slip
246 4/2/2005 9:44:54.5 7.76 94.20 13.0 5.4 4 112 72 215 17 20 157 75 7171 65 81 716 C9 Strike-slip
247 5/2/2005 8:0:30.5 8.06 94.26 12.0 5.4 8 122 7 31 79 260 221 37 778 26 54 799 C9 Normal
248 5/2/2005 17:35:47.1 8.08 94.27 15.0 5.9 6 317 84 131 1 227 2 85 176 92 86 5 C9 Strike-slip
249 6/2/2005 6:7:58.6 8.07 94.23 12.0 5.4 1 121 38 30 52 213 243 55 742 360 57 7137 C9 Strike-slip
250 10/2/2005 1:34:32.1 8.01 94.20 12.0 5.0 8 125 31 220 58 23 184 46 7136 60 60 753 C9 Normal
(continued)
19
20
251 16/2/2005 8:19:45.6 8.17 94.23 13.0 5.9 6 306 84 123 0 216 351 85 176 82 86 5 C9 Strike-slip
252 24/2/2005 15:6:51.7 8.68 93.76 28.0 4.8 3 262 17 171 73 2 9 45 765 157 50 7112 C9 Normal
253 25/2/2005 13:31:16.4 7.71 94.23 15.0 5.6 13 109 59 221 28 12 153 61 7169 58 80 730 C9 Strike-slip
254 11/3/2005 12:59:54.9 7.47 94.38 12.8 5.1 16 98 58 215 27 359 141 59 7172 47 83 731 C9 Strike-slip
255 26/4/2005 14:1:43.9 7.74 94.04 12.0 4.9 12 106 19 11 67 225 219 37 757 360 59 7113 C9 Normal
256 27/4/2005 14:4:47.4 8.66 93.72 17.9 5.0 1 112 27 21 63 205 227 50 753 358 52 7125 C9 Normal
257 13/6/2005 19:28:17.2 7.68 94.06 12.0 5.3 16 106 34 5 51 218 235 41 732 350 69 7126 C9 Normal
258 27/6/2006 15:2:22 8.81 93.75 19.5 5.1 0 78 63 168 27 347 126 71 7160 29 71 720 C9 Strike-slip
259 29/1/2007 19:48:40.8 8.37 93.76 77.3 5.5 30 98 57 251 12 1 136 60 167 233 78 31 C9 Strike-slip
260 31/5/2007 23:18:5.1 8.31 94.03 12.0 5.5 20 83 63 218 17 346 124 63 178 215 88 27 C9 Strike-slip
261 15/7/2005 12:50:7.7 7.56 94.30 13.9 4.9 16 112 39 215 47 4 161 45 7153 51 71 748 C9 Normal
262 9/8/2005 11:23:2.7 7.78 94.33 24.0 5.4 15 104 73 256 7 12 147 74 175 239 85 16 C9 Strike-slip
263 18/9/2005 3:47:41.8 7.60 94.16 12.0 5.1 25 103 2 194 65 289 189 20 796 15 70 788 C9 Normal
264 6/10/2005 2:53:0.9 7.74 93.98 18.6 4.9 16 107 25 10 60 228 229 36 745 358 66 7117 C9 Normal
265 21/11/2007 19:4:2.1 7.76 93.79 17.8 4.9 5 341 10 71 79 226 60 41 7105 260 50 777 C9 Normal
266 21/11/2007 19:4:2.1 7.76 93.79 17.8 4.9 5 341 10 71 79 226 60 41 7105 260 50 777 C9 Normal
267 13/2/1982 19:56:16.9 5.81 94.68 66.2 5.7 21 52 68 219 4 320 94 72 168 188 78 19 C10 Strike-slip
268 30/1/1983 1:26:3 5.36 94.84 75.4 5.2 19 47 23 308 59 173 169 32 744 298 68 7115 C10 Normal
269 4/4/1983 2:51:43.7 5.72 94.65 71.6 7.0 61 51 29 234 1 143 207 51 51 78 53 127 C10 Thrust
270 2/7/1983 9:34:8.4 5.81 94.75 87.1 5.8 61 69 28 230 8 325 83 44 132 211 59 57 C10 Thrust
271 17/9/1983 5:56:59.5 4.60 95.10 45.2 6.1 17 49 40 304 45 157 182 45 725 289 73 7132 C10 Normal
272 27/12/1988 13:50:43.6 4.65 95.21 111.4 5.3 24 10 30 114 50 247 56 34 7152 303 75 759 C10 Normal
273 4/1/2005 19:8:6.5 5.17 94.29 34.4 5.2 64 81 6 340 26 247 323 20 73 162 71 96 C10 Thrust
274 5/1/2005 14:34:35.4 5.20 94.63 52.9 5.3 75 21 7 138 13 230 329 33 103 134 58 82 C10 Thrust
275 5/1/2005 14:54:6.2 5.32 94.24 33.0 5.9 66 47 2 142 24 232 326 21 95 141 69 88 C10 Thrust
276 6/1/2005 0:56:31.2 5.02 94.60 54.0 5.7 73 27 6 136 16 228 327 29 102 133 62 83 C10 Thrust
277 16/3/2006 15:12:16.8 4.84 94.64 46.5 5.0 72 18 7 131 16 223 324 29 105 127 62 82 C10 Thrust
278 17/8/2000 18:40:12.6 5.77 94.63 65.8 5.7 12 52 68 174 18 319 96 69 7175 5 86 721 C10 Strike-slip
279 31/10/2001 22:4:39.2 5.21 94.20 34.4 5.7 9 266 23 0 65 156 331 41 7126 195 58 763 C10 Normal
280 27/12/2004 0:32:20.2 5.36 94.33 39.0 5.8 69 55 1 321 21 230 318 24 87 142 66 92 C10 Thrust
281 11/1/2005 21:46:36.4 4.74 94.63 48.0 5.0 75 37 2 133 15 223 316 30 93 132 60 88 C10 Thrust
282 12/1/2005 13:58:22.7 5.33 94.51 43.0 5.4 72 34 4 137 17 228 324 28 99 135 62 85 C10 Thrust
283 12/1/2005 18:44:47.4 5.16 94.41 47.2 5.1 70 53 3 151 20 242 338 25 97 150 65 87 C10 Thrust
284 4/5/2005 5:58:54 4.60 94.87 42.0 5.3 16 46 60 166 25 308 89 60 7174 355 84 730 C10 Strike-slip
285 5/5/2005 1:14:52.6 5.18 94.18 38.4 5.0 75 63 1 156 15 246 337 30 91 155 60 89 C10 Thrust
286 9/5/2005 1:30:56 4.85 94.76 40.0 5.2 71 39 2 135 19 226 319 26 95 134 64 88 C10 Thrust
287 12/5/2005 16:4:29 5.01 94.47 19.0 5.2 54 77 0 168 36 258 349 9 91 168 81 90 C10 Thrust
288 21/5/2005 23:1:17.2 5.03 94.71 44.0 5.6 68 37 4 137 21 228 325 24 100 135 66 86 C10 Thrust
289 31/5/2005 2:29:36.3 5.23 94.57 20.5 5.5 49 105 7 7 40 272 311 8 33 188 86 97 C10 Thrust
290 31/5/2005 7:28:5.9 5.21 94.60 52.4 5.0 75 31 7 149 13 240 340 32 103 144 59 82 C10 Thrust
291 27/12/2004 8:21:41.5 5.20 94.48 55.1 5.3 76 47 1 315 14 225 314 31 89 135 59 91 C10 Thrust
292 27/12/2004 9:39:10.6 5.21 94.48 41.0 6.0 66 38 3 134 24 225 320 21 97 133 69 87 C10 Thrust
(continued)
293 28/12/2004 14:30:44.7 4.49 95.06 46.3 5.0 17 47 72 248 6 139 184 74 8 92 82 163 C10 Strike-slip
294 29/12/2004 7:52:56.6 5.01 94.82 17.5 5.3 46 40 8 138 43 236 35 8 167 138 88 82 C10 Thrust
295 29/12/2004 15:50:9 5.36 94.53 48.5 5.1 74 35 5 142 15 233 330 30 99 139 61 85 C10 Thrust
296 29/12/2004 18:50:23 5.33 94.13 43.4 5.4 72 35 4 136 17 228 323 28 98 135 62 86 C10 Thrust
297 29/12/2004 21:13:3.1 5.13 94.61 41.0 5.6 28 35 32 144 45 273 76 34 7162 331 80 758 C10 Normal
298 30/12/2004 4:27:39 5.34 94.29 36.3 5.2 69 31 6 137 20 229 330 26 104 135 65 83 C10 Thrust
299 30/12/2004 21:36:5.1 5.12 94.28 42.0 5.4 72 34 5 140 17 232 330 28 101 138 62 84 C10 Thrust
300 30/12/2004 23:4:58.8 5.24 94.30 43.8 4.9 74 333 15 126 7 218 324 40 113 115 54 72 C10 Thrust
301 31/12/2004 10:58:28.6 4.85 94.57 49.2 5.2 75 29 4 136 14 227 324 31 99 134 60 85 C10 Thrust
302 31/12/2004 14:38:47.6 4.79 94.66 49.6 5.4 73 36 2 132 17 223 316 28 94 131 62 88 C10 Thrust
303 31/12/2004 17:48:8.2 4.68 95.09 24.0 5.9 48 46 0 137 42 227 326 3 100 137 87 90 C10 Thrust
304 1/1/2005 4:3:14 5.36 94.29 35.0 5.7 65 26 9 135 23 228 335 23 112 131 69 81 C10 Thrust
305 2/1/2005 12:12:17.7 5.41 94.31 34.0 5.3 61 28 11 139 26 234 349 21 122 135 72 78 C10 Thrust
306 2/1/2005 19:35:26.3 5.22 94.15 71.8 5.1 57 37 14 150 29 248 11 21 133 146 75 75 C10 Thrust
307 8/1/2005 5:58:24.2 4.69 94.76 21.8 5.1 49 77 7 175 40 271 55 9 150 175 86 83 C10 Thrust
308 9/1/2005 22:13:0.3 4.63 94.94 46.0 6.0 67 45 1 313 23 223 311 22 88 133 68 91 C10 Thrust
309 22/1/2005 12:58:36.5 4.94 94.74 40.0 4.9 39 57 50 226 5 323 92 59 154 197 68 34 C10 Strike-slip
310 25/1/2005 9:54:26.5 5.15 94.60 58.6 5.0 76 39 1 133 14 223 314 31 92 132 59 89 C10 Thrust
311 26/1/2005 23:43:29.8 5.07 94.36 51.9 5.1 71 70 1 162 19 253 344 26 92 162 64 89 C10 Thrust
312 27/1/2005 20:9:56.1 5.41 94.24 31.0 5.5 64 38 4 137 25 229 329 20 103 136 70 85 C10 Thrust
313 29/1/2005 2:55:22.8 4.84 94.52 52.0 5.1 73 66 6 318 16 226 308 29 78 141 62 96 C10 Thrust
314 29/1/2005 18:21:1.8 5.25 94.15 46.0 5.2 76 41 1 135 14 225 316 31 92 134 59 89 C10 Thrust
315 2/2/2005 9:4:29.2 5.17 94.41 32.0 5.2 65 38 5 140 24 232 334 21 105 138 69 84 C10 Thrust
316 9/2/2005 13:27:28.9 4.51 95.03 47.0 6.0 70 43 1 312 20 222 310 25 89 132 65 91 C10 Thrust
317 13/2/2005 1:22:11.4 4.82 94.61 51.0 5.4 73 25 5 133 16 225 323 30 101 130 61 84 C10 Thrust
318 13/2/2005 2:2:8.6 4.85 94.70 42.0 5.2 71 30 5 134 18 225 323 27 100 132 63 85 C10 Thrust
319 18/2/2005 19:33:48 5.31 94.35 36.0 5.6 66 33 5 135 23 227 327 22 103 133 68 85 C10 Thrust
320 19/2/2005 23:45:16 4.97 94.37 33.9 4.8 81 349 9 155 2 246 345 44 103 147 48 78 C10 Thrust
321 12/3/2005 22:33:14.9 5.16 94.62 54.6 5.2 76 54 3 313 14 223 309 31 85 135 59 93 C10 Thrust
322 13/3/2005 22:12:48.3 5.42 94.42 42.0 5.4 70 25 8 138 18 231 334 28 107 134 63 81 C10 Thrust
323 16/3/2005 6:39:52.7 5.37 94.32 35.0 5.4 61 20 13 135 25 231 349 23 126 131 72 76 C10 Thrust
324 17/3/2005 23:20:51.2 4.66 94.93 45.0 5.8 68 42 0 133 22 223 313 23 90 133 67 90 C10 Thrust
325 25/3/2005 1:4:55.2 5.30 94.25 34.0 5.9 66 45 3 141 24 232 328 22 97 140 69 87 C10 Thrust
326 30/3/2005 23:17:15.5 5.46 94.19 38.9 5.0 83 77 0 168 7 258 348 38 90 168 52 90 C10 Thrust
327 31/3/2005 14:27:32.9 5.09 94.54 36.2 4.8 77 97 6 342 12 251 333 33 79 166 57 97 C10 Thrust
328 4/4/2005 19:37:10.4 4.75 94.73 42.8 4.8 1 338 17 68 73 245 51 47 7114 264 48 767 C10 Normal
329 17/6/2005 2:37:41 5.33 94.64 46.0 5.3 70 19 10 139 17 232 337 30 111 133 62 79 C10 Thrust
330 13/8/2006 8:41:51.3 5.27 94.54 54.3 5.2 75 27 4 133 15 224 320 31 99 130 60 85 C10 Thrust
331 16/9/2006 6:17:47.2 4.84 94.59 49.3 5.3 70 8 11 130 16 224 330 30 112 125 62 78 C10 Thrust
332 12/10/2006 5:30:40 4.80 95.09 41.0 5.0 84 135 6 312 0 42 138 45 98 306 46 82 C10 Thrust
333 9/12/2006 9:24:50.4 4.80 94.59 53.3 5.1 76 36 2 135 13 226 319 32 94 134 58 87 C10 Thrust
334 17/12/2006 21:10:26 4.58 94.89 54.4 5.8 72 38 1 131 18 222 314 27 93 131 63 89 C10 Thrust
(continued)
21
22
335 3/1/2007 12:47:33.7 5.25 94.28 44.0 5.4 71 25 7 136 18 228 329 28 105 132 63 82 C10 Thrust
336 27/4/2007 8:2:52.2 5.09 94.43 49.2 5.9 70 38 2 134 20 225 319 25 95 133 65 88 C10 Thrust
337 1/5/2007 19:44:20.9 5.29 94.38 51.2 5.0 73 9 11 137 13 230 334 33 110 131 59 77 C10 Thrust
338 24/6/2007 13:47:40.3 5.21 94.50 54.0 5.0 77 37 1 134 13 224 316 32 93 133 58 88 C10 Thrust
339 23/7/2005 0:45:1.4 5.45 94.37 32.0 5.0 64 71 1 339 26 249 336 19 87 160 71 91 C10 Thrust
340 23/7/2005 22:53:38.5 5.03 94.47 46.9 5.3 71 19 10 141 16 234 338 31 110 135 62 78 C10 Thrust
341 30/7/2005 15:13:23.4 5.16 94.32 31.0 5.8 56 26 12 135 31 232 356 18 133 132 77 77 C10 Thrust
342 2/8/2005 20:56:40.6 5.22 94.25 34.5 5.0 78 32 4 140 11 231 326 34 97 138 56 86 C10 Thrust
343 26/8/2005 0:36:56.5 5.13 94.58 62.2 4.8 78 62 4 313 11 222 307 34 83 136 56 95 C10 Thrust
344 28/8/2005 4:43:42.3 5.30 94.57 43.0 5.3 71 26 6 132 19 224 323 27 102 130 64 84 C10 Thrust
345 1/9/2005 16:42:42.7 4.77 94.63 51.0 5.1 73 14 8 134 14 226 328 32 106 129 60 80 C10 Thrust
346 7/9/2005 6:42:54.1 5.05 94.66 60.4 5.0 71 84 13 313 14 220 293 33 66 141 60 105 C10 Thrust
347 10/9/2005 16:57:51.3 4.61 94.98 46.0 5.8 68 37 1 130 22 220 313 23 93 129 67 89 C10 Thrust
348 3/10/2005 22:9:27.3 5.31 94.35 34.0 5.5 64 23 8 129 25 223 330 21 112 126 71 82 C10 Thrust
349 4/10/2005 12:23:26.9 5.37 94.14 41.1 5.0 72 34 5 139 17 231 328 28 100 137 62 85 C10 Thrust
350 11/10/2005 15:5:44 4.49 95.02 49.0 5.9 70 42 0 311 20 221 311 25 89 131 65 90 C10 Thrust
351 13/1/2006 14:47:33.5 4.86 94.49 40.5 4.8 71 26 7 137 18 229 330 28 105 133 63 82 C10 Thrust
352 15/2/2006 1:17:56 5.26 94.18 46.7 4.8 70 349 15 125 14 218 328 34 117 116 60 73 C10 Thrust
353 26/2/2006 21:32:53.4 5.27 94.59 53.8 5.2 73 19 8 136 15 228 328 31 105 131 60 81 C10 Thrust
354 13/5/2006 3:11:44.2 5.33 94.30 43.1 5.7 72 47 1 139 18 229 320 28 91 139 63 89 C10 Thrust
355 14/6/2006 0:14:33.7 5.27 94.41 52.3 5.2 71 12 11 139 15 232 338 32 112 132 61 77 C10 Thrust
356 5/1/2008 20:1:56.9 5.21 94.62 56.7 5.3 74 13 8 130 14 222 323 32 104 126 59 81 C10 Thrust
357 5/3/2008 17:4:6 4.68 94.71 49.8 5.0 75 23 5 130 14 221 318 31 99 127 60 85 C10 Thrust
358 8/5/2008 11:31:26.6 5.21 94.49 52.8 5.0 73 358 10 123 14 215 318 32 108 117 59 79 C10 Thrust
359 23/7/1991 13:25:48.4 3.90 95.83 42.3 5.6 36 359 10 261 52 158 132 13 738 260 82 7100 C11 Normal
360 19/3/2006 4:24:35.8 3.84 95.96 56.6 5.2 54 116 27 340 21 239 291 34 35 170 71 118 C11 Thrust
361 21/7/2005 1:42:44.7 4.07 96.12 18.6 5.2 9 304 71 62 16 211 348 72 7175 257 85 718 C11 Strike-slip
362 22/9/2005 12:30:9.1 3.74 95.89 46.0 5.1 56 325 24 95 23 196 324 30 143 87 72 65 C11 Thrust
363 25/4/2005 3:18:35.5 3.08 93.87 20.8 4.9 73 110 11 340 12 247 323 34 70 166 58 103 C12 Thrust
364 14/1/2005 21:38:20 3.01 93.81 12.0 5.6 81 126 9 315 1 225 306 44 77 143 47 102 C12 Thrust
365 24/5/2005 9:37:55.2 2.48 94.41 12.0 5.2 76 4 7 124 12 215 315 33 103 119 58 81 C12 Thrust
366 27/12/2004 18:9:32.1 2.61 94.42 12.0 5.3 68 74 7 326 20 234 311 25 74 149 66 98 C12 Thrust
367 28/12/2004 14:48:30.1 3.24 93.68 12.0 4.9 82 284 6 150 6 59 142 39 81 334 51 98 C12 Thrust
368 29/12/2004 14:3:24.3 3.19 93.80 12.8 5.1 76 229 3 331 14 62 156 31 96 330 59 86 C12 Thrust
369 23/1/2005 20:36:8.9 2.66 94.31 16.6 5.2 22 310 62 169 16 47 90 63 5 358 86 153 C12 Strike-slip
370 29/1/2005 6:10:44 3.21 93.59 12.0 5.5 86 132 4 329 1 239 325 44 85 152 46 95 C12 Thrust
371 29/1/2005 7:21:45.2 3.04 93.74 12.0 5.2 62 320 27 157 7 63 125 45 49 356 58 123 C12 Thrust
372 1/2/2005 17:14:3.2 2.67 94.21 12.0 4.8 78 223 1 130 12 40 129 33 89 311 57 91 C12 Thrust
373 21/2/2005 6:10:11.7 3.25 93.67 12.0 5.2 77 179 11 325 7 57 159 39 108 317 53 76 C12 Thrust
374 27/7/2005 14:5:29 3.28 93.73 18.7 4.7 74 190 11 321 12 53 157 34 109 314 58 77 C12 Thrust
375 2/12/2005 3:8:1.4 3.18 93.82 18.6 4.8 79 165 10 318 5 49 150 41 105 310 51 77 C12 Thrust
376 22/3/1982 8:38:36.1 1.92 96.85 15.0 5.6 59 73 14 318 27 221 281 22 51 143 73 104 C13 Thrust
(continued)
377 20/12/1988 3:35:16.9 1.87 97.16 15.0 5.5 47 27 3 120 43 212 349 4 139 119 88 87 C13 Thrust
378 2/8/1989 10:24:29 2.66 95.92 50.8 5.4 63 7 16 132 21 229 345 28 126 125 67 72 C13 Thrust
379 15/4/2005 13:8:56 2.88 96.34 12.0 5.3 74 279 0 10 16 100 191 29 91 10 61 89 C13 Thrust
380 17/4/2005 13:43:55.2 0.31 97.75 12.0 5.4 37 68 3 336 52 241 178 8 767 335 82 793 C13 Normal
381 18/4/2005 13:25:38.2 0.87 97.12 30.1 5.0 66 43 3 141 24 232 330 22 99 139 69 86 C13 Thrust
382 24/4/2005 10:59:7 2.09 96.22 36.0 4.7 67 358 12 118 19 212 321 28 115 112 65 77 C13 Thrust
383 25/4/2005 13:58:35.3 2.27 96.80 31.3 4.8 60 91 22 317 19 219 277 32 45 146 68 114 C13 Thrust
384 12/3/2006 19:44:54 1.30 97.13 32.0 4.8 65 352 16 118 19 214 328 29 124 111 66 73 C13 Thrust
385 1/9/1993 14:3:23.5 2.85 95.92 15.0 6.3 54 43 1 311 36 221 306 9 85 132 81 91 C13 Thrust
386 31/10/1994 11:48:18.3 2.63 96.00 37.2 6.2 64 59 12 304 23 209 276 24 59 129 69 103 C13 Thrust
387 14/3/1995 10:27:34.1 2.78 95.63 29.4 5.5 71 53 5 308 18 217 299 27 79 131 64 95 C13 Thrust
388 3/6/1995 11:57:36.9 2.91 95.62 48.9 5.1 70 5 10 122 18 215 320 29 110 117 63 79 C13 Thrust
389 22/11/1995 13:27:58.2 2.85 95.72 34.8 5.8 65 65 11 310 22 216 285 25 63 135 68 102 C13 Thrust
390 13/9/1996 5:4:40.8 3.04 95.52 34.6 5.3 71 19 7 131 17 223 324 29 105 127 62 82 C13 Thrust
391 7/7/1997 11:24:41.8 0.86 97.16 32.2 5.9 59 55 6 316 31 222 294 15 68 137 76 96 C13 Thrust
392 24/2/1999 7:20:48.3 3.08 96.32 24.5 5.4 49 41 10 300 39 202 237 11 27 121 85 100 C13 Thrust
393 7/3/2001 8:29:26.7 0.34 97.68 36.2 5.1 57 69 15 315 29 217 272 21 45 139 75 105 C13 Thrust
394 2/11/2002 1:26:25.9 2.65 95.99 23.0 7.3 60 52 5 314 30 221 297 16 73 135 75 95 C13 Thrust
395 2/11/2002 9:46:53.4 2.89 96.05 27.0 6.3 55 77 7 336 34 241 303 13 56 158 79 98 C13 Thrust
396 13/11/2002 15:53:12.6 2.86 95.74 31.0 5.6 63 41 3 306 27 214 297 18 81 127 72 93 C13 Thrust
397 30/11/2002 4:7:9.9 2.51 96.11 41.1 5.2 30 97 47 328 27 204 242 47 2 150 88 137 C13 Strike-slip
398 28/6/2003 7:36:45.8 2.77 95.76 20.0 5.2 39 84 29 327 38 213 239 29 1 148 89 119 C13 Thrust
399 15/9/2003 12:14:34.8 2.16 96.12 38.9 5.1 54 80 31 293 16 193 247 40 36 128 68 124 C13 Thrust
400 11/5/2004 8:28:51.3 0.18 97.58 24.0 6.1 59 35 3 130 31 222 322 14 102 130 76 87 C13 Thrust
401 17/7/2004 13:38:4.8 1.07 97.36 38.2 5.1 55 101 31 311 14 212 267 41 38 146 66 125 C13 Thrust
402 4/5/2005 0:42:2.6 0.23 96.89 15.2 5.2 6 65 62 167 27 332 112 67 7164 16 76 724 C13 Strike-slip
403 4/5/2005 0:44:50.1 2.80 96.17 50.6 5.1 0 292 68 22 22 202 339 74 7164 245 75 716 C13 Strike-slip
404 10/5/2005 22:22:47.6 0.90 97.10 20.0 5.1 60 40 1 131 30 222 314 15 92 131 75 89 C13 Thrust
405 10/5/2005 22:29:44.9 0.93 97.00 22.0 5.3 64 52 2 318 26 227 312 19 84 139 71 92 C13 Thrust
406 16/5/2005 9:58:51.7 0.63 97.73 21.6 5.1 66 100 3 4 24 273 357 21 83 185 69 93 C13 Thrust
407 19/5/2005 1:55:2.5 1.88 96.74 12.0 6.9 52 49 3 315 38 222 290 8 65 135 83 93 C13 Thrust
408 19/5/2005 20:44:7.9 0.49 97.26 19.4 5.0 26 35 9 301 63 193 144 21 765 298 71 799 C13 Normal
409 21/5/2005 9:43:52.2 1.09 97.18 36.0 5.1 49 325 37 116 14 217 346 45 149 99 69 50 C13 Thrust
410 23/5/2005 5:48:23.8 0.70 97.26 33.0 4.9 75 32 4 137 15 228 323 31 98 134 60 85 C13 Thrust
411 24/5/2005 11:38:43.9 1.21 97.23 31.6 4.8 39 108 46 320 17 211 257 50 19 155 76 138 C13 Strike-slip
412 25/5/2005 18:47:45.5 1.32 97.24 33.4 4.9 75 59 5 311 14 219 303 31 81 133 59 96 C13 Thrust
413 3/6/2005 0:42:4.7 1.21 96.96 12.0 5.8 55 41 4 137 35 230 338 11 112 136 80 86 C13 Thrust
414 27/12/2004 6:59:15.2 2.95 95.42 13.1 5.6 40 42 5 307 50 211 174 7 743 307 85 795 C13 Normal
415 27/12/2004 20:10:52.4 2.92 95.49 12.0 5.8 79 148 11 324 1 54 155 45 106 313 47 75 C13 Thrust
416 1/1/2005 23:40:32.6 2.74 96.33 57.7 4.9 69 87 15 313 14 219 289 33 62 141 61 107 C13 Thrust
417 15/1/2005 16:44:7.1 2.68 95.98 34.5 4.9 31 324 59 137 3 232 4 67 159 102 71 25 C13 Strike-slip
418 21/1/2005 8:37:4.7 1.37 97.42 31.3 4.8 75 342 11 120 10 212 316 36 110 112 56 76 C13 Thrust
(continued)
23
24
419 26/1/2005 16:50:6.8 2.69 96.21 60.1 4.8 42 94 43 308 18 201 246 47 20 142 75 135 C13 Thrust
420 26/2/2005 12:56:58.1 2.80 95.40 12.0 6.7 51 51 3 318 39 226 294 6 66 139 84 93 C13 Thrust
421 3/3/2005 17:10:23.5 2.77 95.49 40.4 4.8 16 188 3 97 73 358 282 29 784 95 61 793 C13 Normal
422 28/3/2005 16:10:31.5 1.67 97.07 25.8 8.7 52 30 4 125 38 218 333 8 118 125 83 86 C13 Thrust
423 29/3/2005 4:50:8.6 0.30 96.95 28.3 5.5 3 52 21 321 69 150 163 46 760 304 51 7117 C13 Normal
424 29/3/2005 5:16:31 2.39 96.39 30.0 5.9 62 19 3 114 28 205 302 17 99 113 73 87 C13 Thrust
425 29/3/2005 9:42:57.9 0.49 97.10 35.3 5.2 76 43 3 300 14 210 296 32 84 122 59 93 C13 Thrust
426 29/3/2005 14:16:8.6 2.62 95.99 23.0 5.1 18 47 22 310 61 173 167 33 748 300 66 7114 C13 Normal
427 29/3/2005 18:29:47.5 1.01 97.73 18.0 5.0 16 350 0 260 74 170 80 29 790 260 61 790 C13 Normal
428 29/3/2005 20:41:39.3 1.86 97.02 58.5 5.2 72 84 15 300 10 207 279 37 65 130 57 108 C13 Thrust
429 30/3/2005 0:25:52.9 0.78 97.16 33.0 5.0 72 347 13 121 13 213 320 34 113 113 59 75 C13 Thrust
430 30/3/2005 23:12:6 1.03 97.08 30.6 5.0 65 358 16 124 19 220 334 29 123 117 66 73 C13 Thrust
431 30/3/2005 23:19:16.1 1.14 96.91 36.8 4.9 83 353 7 161 2 252 349 44 101 154 47 80 C13 Thrust
432 30/3/2005 23:40:49.2 1.50 96.84 24.0 5.2 58 63 13 311 28 213 271 21 49 135 75 104 C13 Thrust
433 31/3/2005 8:30:28.8 2.65 96.14 24.0 5.0 15 73 25 336 60 192 194 37 745 323 65 7118 C13 Normal
434 31/3/2005 16:30:1.8 1.21 96.94 30.0 5.0 73 34 4 138 16 229 325 29 99 135 61 85 C13 Thrust
435 31/3/2005 18:2:35.2 0.29 97.57 17.5 4.9 69 1 8 114 19 207 311 27 109 110 65 81 C13 Thrust
436 1/4/2005 0:49:42 0.51 97.15 16.7 5.0 23 117 62 332 14 213 256 63 7 163 84 153 C13 Strike-slip
437 1/4/2005 7:40:29.1 2.35 96.18 12.0 4.9 55 39 4 135 35 228 337 11 112 134 80 86 C13 Thrust
438 1/4/2005 10:37:46.1 2.80 96.34 12.0 5.2 8 314 4 45 81 161 39 37 797 228 53 785 C13 Normal
439 1/4/2005 14:18:17.6 2.20 96.65 36.3 4.8 75 63 6 311 14 219 301 31 79 134 59 97 C13 Thrust
440 1/4/2005 17:24:50 1.16 97.23 21.0 5.1 66 62 8 315 23 221 297 23 70 138 68 98 C13 Thrust
441 2/4/2005 3:37:22 0.75 97.17 12.0 5.0 2 289 75 26 15 199 335 78 7171 243 81 712 C13 Strike-slip
442 2/4/2005 16:24:14.7 2.68 96.35 19.0 5.0 9 133 12 225 75 9 209 38 7110 54 55 775 C13 Normal
443 3/4/2005 12:21:20.5 2.89 96.32 17.8 5.1 80 290 1 28 10 118 210 35 92 27 55 88 C13 Thrust
444 3/4/2005 20:23:36.3 1.98 96.72 35.3 4.8 72 38 0 306 18 216 305 27 89 127 63 91 C13 Thrust
445 3/4/2005 22:31:56.9 1.00 97.17 33.2 4.8 74 42 10 172 12 264 7 34 108 165 58 78 C13 Thrust
446 4/4/2005 11:5:45.2 1.18 97.17 30.5 4.9 68 341 19 131 10 225 337 39 122 119 58 67 C13 Thrust
447 5/4/2005 9:37:30 1.58 97.00 43.4 5.2 0 298 77 29 13 208 344 81 7171 253 81 710 C13 Strike-slip
448 6/4/2005 10:11:39 2.37 96.15 27.5 4.9 82 67 3 183 7 273 7 38 96 180 52 86 C13 Thrust
449 7/4/2005 2:21:30.4 1.09 96.98 23.0 5.0 67 17 11 134 20 229 338 27 116 129 66 78 C13 Thrust
450 7/4/2005 11:46:2.8 0.52 97.31 12.0 5.6 41 97 49 276 0 7 134 62 149 239 63 31 C13 Strike-slip
451 7/4/2005 11:50:26.2 0.88 97.40 34.8 5.2 72 146 12 276 13 9 114 33 111 269 59 77 C13 Thrust
452 7/4/2005 15:24:5.4 1.30 96.88 26.0 5.1 63 70 6 328 26 235 312 20 73 150 71 96 C13 Thrust
453 8/4/2005 1:51:38.4 0.50 97.34 12.0 5.7 5 282 82 51 6 191 326 82 7179 236 89 78 C13 Strike-slip
454 9/4/2005 19:3:36.7 1.14 96.94 29.0 4.9 72 11 14 153 11 246 353 37 115 143 57 73 C13 Thrust
455 25/4/2005 20:18:30.6 0.48 97.11 12.0 5.3 17 34 20 298 63 161 152 33 751 288 65 7112 C13 Normal
456 25/4/2005 20:22:18 0.47 97.45 31.3 4.8 14 25 38 283 48 131 154 45 730 266 69 7131 C13 Normal
457 25/4/2005 21:40:16.4 0.43 97.28 13.2 5.2 25 50 0 140 65 230 140 20 790 320 70 790 C13 Normal
458 26/4/2005 17:18:26.3 1.14 97.01 19.0 5.3 57 37 4 132 32 224 327 13 106 131 77 86 C13 Thrust
459 2/5/2005 12:3:21.2 1.18 96.95 29.1 4.8 66 75 10 322 22 228 300 25 66 146 67 101 C13 Thrust
460 11/6/2005 3:47:47 0.80 97.29 26.0 5.2 61 36 3 131 29 223 321 17 100 130 74 87 C13 Thrust
(continued)
461 21/6/2006 8:53:35.7 0.95 97.01 34.3 4.9 70 68 9 311 18 218 293 29 70 136 63 101 C13 Thrust
462 27/7/2006 11:16:44.5 1.66 97.01 15.0 6.3 50 38 2 131 40 223 336 5 115 131 85 88 C13 Thrust
463 3/9/2006 16:20:34.9 0.10 97.11 30.5 5.5 21 50 1 140 69 234 137 24 793 321 66 789 C13 Normal
464 4/10/2006 13:33:49.1 1.15 97.61 37.3 5.0 69 336 17 121 11 214 325 37 120 110 59 70 C13 Thrust
465 6/10/2006 14:49:4.2 0.76 97.22 34.5 5.3 56 332 28 113 18 213 339 36 142 101 69 60 C13 Thrust
466 25/10/2006 5:6:6.7 0.93 97.12 30.8 5.2 68 36 5 138 22 229 328 24 102 135 67 85 C13 Thrust
467 25/10/2006 5:19:48.6 0.78 97.26 35.7 5.0 74 34 1 129 16 219 311 29 93 128 61 88 C13 Thrust
468 9/11/2006 15:55:48.9 1.03 97.19 18.2 5.2 26 355 7 88 63 192 70 20 7109 271 71 783 C13 Normal
469 25/1/2007 15:18:40.1 1.36 97.03 39.6 5.1 62 331 23 115 15 212 331 37 132 103 64 64 C13 Thrust
470 14/2/2007 19:50:2.1 0.33 97.22 12.0 5.7 70 328 17 116 10 209 320 38 119 105 57 69 C13 Thrust
471 14/2/2007 20:46:34.2 0.39 97.17 12.0 5.5 69 327 14 98 15 191 300 32 116 90 61 74 C13 Thrust
472 18/2/2007 10:45:29.1 0.98 97.26 30.9 5.1 70 44 2 139 20 230 323 25 94 138 65 88 C13 Thrust
473 1/3/2007 2:1:5.8 3.60 96.23 43.4 5.3 52 55 33 203 16 303 71 41 146 188 69 54 C13 Thrust
474 7/4/2007 9:51:54.4 2.74 95.48 12.0 6.1 52 51 3 317 38 225 293 8 65 138 83 93 C13 Thrust
475 8/9/2007 11:31:48.4 0.10 97.62 35.9 5.1 71 24 3 123 18 214 309 27 97 121 64 87 C13 Thrust
476 29/9/2007 5:37:8.8 2.71 95.39 15.0 6.0 52 56 4 321 38 227 288 8 57 141 83 94 C13 Thrust
477 18/6/2005 12:36:18.9 1.41 97.44 35.5 4.8 28 308 61 133 2 39 87 69 19 350 72 157 C13 Strike-slip
478 19/6/2005 12:45:2 1.09 97.09 21.0 5.0 69 45 1 139 21 229 322 24 93 138 66 89 C13 Thrust
479 27/6/2005 17:14:32.1 1.25 97.20 22.0 4.8 66 354 17 129 16 224 338 33 123 120 63 71 C13 Thrust
480 2/7/2005 9:10:37.9 1.09 96.95 12.0 5.0 55 59 1 328 35 238 325 10 87 148 80 91 C13 Thrust
481 5/7/2005 1:52:6.3 1.56 96.93 16.0 6.7 52 39 2 132 38 223 329 8 107 131 83 88 C13 Thrust
482 8/7/2005 21:28:20 0.88 97.29 12.0 4.7 28 300 56 84 17 201 337 57 171 72 82 33 C13 Strike-slip
483 11/7/2005 14:36:10.8 0.93 97.00 22.0 5.6 61 43 1 135 29 226 319 16 94 135 74 89 C13 Thrust
484 22/7/2005 9:50:7.2 2.27 96.97 15.0 5.2 44 36 2 304 46 211 189 3 725 304 89 792 C13 Normal
485 26/7/2005 1:39:3.7 1.75 97.08 41.2 5.0 44 310 44 109 11 209 339 51 153 87 69 42 C13 Strike-slip
486 27/7/2005 13:57:19.4 2.52 96.04 33.6 4.8 74 32 0 123 16 213 303 29 91 122 61 90 C13 Thrust
487 30/7/2005 0:36:31.9 0.91 97.13 26.0 5.3 55 41 6 139 34 233 346 12 118 138 79 84 C13 Thrust
488 30/7/2005 21:17:16.1 0.26 97.39 22.2 4.8 6 225 32 131 57 324 345 48 745 109 58 7129 C13 Normal
489 31/7/2005 12:37:29.5 0.39 97.67 37.6 5.0 70 354 13 124 15 218 327 32 116 117 61 75 C13 Thrust
490 1/8/2005 13:17:53.4 1.41 97.35 32.4 4.7 49 330 39 126 12 226 354 47 148 106 67 48 C13 Thrust
491 13/8/2005 18:27:27.6 1.20 96.95 22.0 5.1 64 43 2 137 25 227 321 20 95 136 70 88 C13 Thrust
492 26/8/2005 6:7:1.7 1.93 96.80 32.0 4.8 80 23 6 150 8 240 337 38 99 145 53 83 C13 Thrust
493 28/8/2005 5:34:47.2 1.40 97.08 23.0 5.0 70 41 2 135 20 226 319 25 94 135 65 88 C13 Thrust
494 16/9/2005 17:19:35.5 2.47 96.17 31.4 4.8 69 80 13 313 16 219 290 31 64 140 63 105 C13 Thrust
495 19/9/2005 14:35:5.9 1.40 97.31 33.3 4.9 56 320 33 124 7 219 341 47 138 102 60 51 C13 Thrust
496 4/11/2005 17:44:49.9 0.97 96.96 21.0 5.5 61 42 2 136 28 226 321 17 96 135 74 88 C13 Thrust
497 22/11/2005 14:4:36.8 0.46 97.19 29.4 5.0 58 236 22 106 22 6 61 30 41 294 71 113 C13 Thrust
498 27/11/2005 23:31:40 0.92 96.98 22.0 5.6 62 37 5 136 28 229 332 18 106 135 73 85 C13 Thrust
499 3/12/2005 18:48:11.2 1.10 97.08 25.8 4.9 50 119 29 347 24 242 288 33 27 175 75 120 C13 Thrust
500 4/12/2005 14:9:32.7 0.65 97.43 39.0 4.9 9 126 71 9 16 219 261 72 76 353 85 7162 C13 Strike-slip
501 6/12/2005 5:40:20.7 2.32 96.48 34.4 4.8 64 323 24 118 10 212 328 41 128 103 59 62 C13 Thrust
502 7/12/2005 2:19:31.3 1.11 96.90 32.5 5.2 68 46 0 316 22 226 315 23 90 136 67 90 C13 Thrust
(continued)
25
26
503 7/12/2005 8:38:22.5 0.20 97.27 14.5 4.8 68 309 17 169 14 75 143 35 59 359 61 110 C13 Thrust
504 13/1/2006 10:50:5.5 1.22 97.58 31.2 5.1 71 358 13 131 14 224 332 34 115 123 60 74 C13 Thrust
505 13/1/2006 22:47:35.8 1.35 97.28 34.6 4.9 33 118 54 326 14 217 263 57 15 164 77 146 C13 Strike-slip
506 31/1/2006 19:15:53.9 2.34 95.90 23.0 5.9 62 55 7 312 27 219 293 19 70 134 72 97 C13 Thrust
507 6/2/2006 12:40:40.9 2.59 95.88 29.2 4.8 9 71 21 338 67 182 185 41 756 323 57 7116 C13 Normal
508 6/2/2006 23:55:13.9 1.42 96.87 25.0 5.2 60 23 9 128 28 223 336 19 119 126 74 81 C13 Thrust
509 1/3/2006 14:36:4.8 2.62 95.44 26.2 5.0 64 76 1 344 26 254 341 19 87 164 71 91 C13 Thrust
510 4/4/2006 10:36:59.7 0.36 97.22 12.0 5.2 23 53 15 317 62 196 171 26 752 311 70 7106 C13 Normal
511 25/4/2006 18:26:21.4 1.78 96.77 12.0 6.4 51 50 3 317 39 225 293 7 66 137 84 93 C13 Thrust
512 9/5/2006 3:25:26.2 1.02 97.05 24.0 4.9 67 11 10 126 20 220 328 26 114 122 66 79 C13 Thrust
513 21/11/2007 3:30:15 2.81 96.19 41.0 4.9 69 2 10 119 18 212 318 28 111 114 64 79 C13 Thrust
514 21/11/2007 3:30:15 2.81 96.19 41.0 4.9 69 2 10 119 18 212 318 28 111 114 64 79 C13 Thrust
515 22/12/2007 12:26:21.3 1.92 96.58 25.0 6.1 53 55 4 320 37 227 295 9 65 141 82 94 C13 Thrust
516 22/1/2008 17:15:1.8 0.87 97.18 23.0 6.2 62 42 4 140 28 232 332 17 103 138 73 86 C13 Thrust
517 24/1/2008 12:4:20.7 0.92 97.01 24.5 5.3 67 34 5 136 23 228 328 23 103 134 68 85 C13 Thrust
518 20/2/2008 8:8:45.4 2.69 95.98 14.9 7.3 56 42 2 309 34 218 299 11 80 130 79 92 C13 Thrust
Table 4. Composite CMT solutions for the Burmese–Andaman and West Sunda Arc system
(reference figures 6–8).
Nodal fault Nodal fault
T axis P axis plane 1 plane 2
Dip Dip
and dip and dip
Cluster no Plunge Azimuth Plunge Azimuth Strike direction Strike direction
Map (refer figs 6a–8a)

C4, C5, C6 648 868 N 248 2668 N 88 N 298 E 1908 N 608 W
C7, C8 128 3448 N 798 1518 N 738 N 338 SE 2528 N 558 NW
C9 168 1098 N 248 68 N 548 N 868 SE 1468 N 628 SW
C10, C11, 758 468 N 258 2258 N 1328 N 648 SW 3198 N 258 NE
C12, C13
Section (reference figures 8(b) and 8(e))
A 688 378 N 228 2298 N 3358 N 268 NE 1358 N 668 SW
B 738 328 N 158 2268 N 3258 N 308 E 1318 N 618 SW

C 658 468 N 248 2198 N 3038 N 198 NE 1328 N 718 SW
D 668 408 N 248 2248 N 3208 N 228 NE 1318 N 698 SW
and normal fault events have predominantly been generated by bending of the
subducting Indian Plate and occurred at the leading edge of the subduction zone and
the trench where the Indian plate descends. The concentration of strike-slip events in
the northern extremity of C4 cluster indicates the strike-slip movement along the
adjacent mantle penetrating hinge fault. Clusters C7 and C8 found below the ASR
exhibit predominantly normal and subordinate strike-slip events that illustrate the
basic tectonic pattern under the spreading arc. The strain partitioning in terms of
normal and strike-slip movement demonstrate dyke intrusion, spreading, rift
formation and collapse of rift wall, rift-related volcanism and generation of
earthquake swarms along ASR (Mukhopadhyay and Dasgupta 2008). The
composite CMT plot of C4, C5 and C6 clusters disposed parallel to the Andaman
trench shows thrust movement along N–S-oriented thrust planes dipping *308
easterly (figure 7(a)). Both compression and tensional directions are oriented E–W
where compression prevails at a shallower angle (248), while extension is taken up at
higher angle (648). This situation gets reversed at C7–C8 clusters along ASR where
overall strain partitioning is normal along ENE–WSW-oriented planes. Overall
compression is at a high angle (798) along NW–SE, whereas extension dominates at a
shallower angle (128) along a NNW–SSE direction (table 4). The tectonics along
clusters C7 and C8 is represented by penetration of crustal scale faults inside the hot
mantle along the upper plate, influence of branches of Kerguelen plume, magmatic
dyke intrusion, rifting and spreading that have been taken place for last 4 Ma. The
cluster has a shallow depth connotation up to 30 km, which by itself is suggestive of
the presence of an upwelling hot mantle underneath it.
4.3 South Andaman Sea Cluster C9

This large cluster has almost equal numbers of normal and strike-slip events. The
distribution of both strike-slip and normal fault events in this cluster zone actually
corresponds to a complex faulting episode: normal faulting for the rift zone and
strike-slip movements for its transgressive regional faults. This cluster is found in the
area where a swarm of events originated within a span of only 6 days between 26 and
31 January 2005, following the occurrence of the great Andaman earthquake (Mw
9.3) of 26 December 2004. The analysis and supporting evidence suggest that the
earthquakes in this cluster are generated by intruding magmatic dykes along the
weak zones in the crust, followed by rifting, spreading and collapse of rift walls
(Mukhopadhyay and Dasgupta 2008). Magma injection in rifted areas commonly
invokes the injection of shallow, vertical, en-echelon dykes extending along a narrow
rift zone, and this injection accounts for the initial strike-slip motion followed by the
collapse of the closely spaced inner rift wall with earthquakes of a normal fault
source mechanism (Hill 1977). Similarly, CMT solutions for 2005 swarm activity
indicate that intrusion of magmatic dyke in the crustal weak zone is documented by
earthquakes showing a strike-slip solution. Subsequent events with a normal fault
mechanism corroborate the rift formation, collapse and its spread. The overall
composite CMT plot (figure 8(c)) indicates a major strike-slip motion with an
appreciable normal component along a steep-dipping (868) NE–SW plane. Both
compressional and tensional axes make a shallow angle (24–168) along the N–S and
ESE–WNW directions respectively (table 4). The composite plot along the WAF
shows primarily a normal with right-lateral strike-slip component along a steep
dipping NE–SW trending surface in the overriding upper plate. Based on evidence
from seismology, bathymetry, gravity, time-dependent pore pressure perturbations,
rift-related volcanism and calculations on phases of rifting, we assume that a nascent
rift is in the process of formation at this location (Mukhopadhyay and Dasgupta
2008, Mukhopadhyay et al. 2010). The orientation of the nascent rift is perpen-
dicular to the regional trend of strike-slip faults of WAF and SFS.
4.4 Offshore Sumatra Clusters: C10–C13

This is by far the largest and most active seismic zone in the whole region. This zone
contains the aftershocks of two great earthquakes of recent times (Sumatra–
Andaman earthquake Mw 9.3 of 26 December 2004 and Banyak Island earthquake
Mw 8.7 of 28 March 2005). The zone (figure 9(a)) is almost exclusively dominated by
earthquakes of thrust mechanisms, related to the underthrusting of the Indian plate
below the Sunda Arc and also from the overriding SE Asian Plate. The overall
orientation of the thrust planes derived from the composite CMT plot is NW–SE
dipping 258 north-easterly (figure 9(a), table 4). P–T axes are orientated NE–SW in
close correspondence to the structural disposition of the arc geometry. The
concentrations of normal fault-related earthquakes in the longitudinal ends of
otherwise thrust-dominated cluster C13 are probably indicative of severe gravity
adjustments following the thrusting events. The association of earthquakes
belonging to both subducting and overriding plates to create the clusters will be
discussed in detail in the following section.
In this section, cluster C10 consists of two clusters A and B (figure 9(b), table 4).
These two clusters belong to the Indian and SE Asian plates. The strain partitioning
and stress distribution is similar in both these clusters depicting consistent thrust
motion along the NW–SE plane (parallel to arc disposition) dipping less than 308
north-easterly. Such consistent thrust plane geometries along subducting and
overriding plates is also noticed in the depth section following the largest cluster C13
in this belt (figure 9(e)). The depth section across cluster C13 shows that it contains
two clusters C (subducting Indian plate cluster) and D (overriding SE Asian plate
cluster). Both these clusters have thrust-dominated movement along the NW–SE
striking plane dipping less than 228 towards the north-east parallel to WSA.
Similar geometry and stress partitioning in both the plates in clusters C10 and
C13 indicate high seismic coupling, with the extreme compressive nature of this
zone resulting from slow subduction of the old Indian plate (Stein and Okal 2007).
Here, a noticeable feature is the absence of trench parallel strike-slip motion that is
otherwise so prominent along the entire belt. The fault unclamping along shallow
dipping thrust planes (5308) resulted in the Sumatra–Andaman earthquake of
2004 (Mw 9.3) and Banyak Island earthquake of 2005 (Mw 8.7) on either side of
the cluster C13 without altering the fault zone frictional condition (Bilek 2007),
having a sharp boundary of separation of aftershocks (Engdahl et al. 2007) along a
NNE–SSW ridge that acts as a separator (Franke et al. 2008). The two
earthquakes have a different strain release pattern (Dewey et al. 2007). The high
seismic coupling breaks down northward in between C10 and C9 (figure 4) due to
the very buoyant warm crust towards the north (from the tomographic results of
Shapiro et al. 2008) where the strike-slip component is dominant again. The zone
also indicates probable crustal heterogeneity as indicated by differential slip along
the rupture plane recorded along the arc during the rupture propagation of the
2004 Andaman Earthquake (Subarya et al. 2006, Banerjee et al. 2007, Rhie et al.
2007). From cluster C9 northward, under the Andaman frontal arc region, the
oblique component of plate motion predominates due to a probable influence
of the aseismic 908 E Ridge on the Indian Plate (Gahalaut et al. 2010), whereas
south to it, compressive components of the thrust realm predominate, as indicated
in the present study. This inference prompts us to believe that future mega-
thrust events (with potential to generate a tsunami in the Indian Ocean) will
only be restricted in between the clusters C10 and C13. The potentiality of this
zone to generate a tsunamogenic earthquake is also discussed elsewhere (Fujii and
Satake 2007, Hébert et al. 2007) along with physical records of tsunami from the
last 1000 years (Monecke et al. 2008). The clusters and intervening zone between
C1 and C10 may spawn moderate magnitude earthquakes resulting from either
strike-slip or normal movement. The occurrence of one major earthquake on
11.8.2009 (mb 7.6; latitude 14.013: longitude 92.923) as a slab bending event with a
normal fault plane solution (NEIC) north of north Andaman Island attests this
conclusion.
5. Seismic potentiality of the large clusters

Seismic potentiality in terms of maximum earthquake size and predictable crustal
movement associated with the five large clusters discussed in the foregoing, namely
C2, C8, C9, C10 and C13, are attempted here. The purpose of this analysis is to
make a statistical inference on the probable size of an earthquake expected from the
large clusters. This is done using an approach discussed by Wells and Coppersmith
(1994). The analysis is based on the length of the major axis of a cluster already
derived (table 2) and by treating it as the ‘potential rupture length’ to predict the
earthquake size depending on the type of movement–strike-slip or thrust.
Maximum seismic potentiality is inferred for cluster C13 that may spawn an
earthquake of estimated size Mw 8.8, with a rupture length of 460 km, having an
anticipated thrust movement. In fact, this zone of seismic cluster has generated two
mega-earthquakes in the recent past: Sumatra–Andaman earthquake Mw 9.3 of 26
December 2004 and the Banyak Island earthquake Mw 8.7 of 28 March 2005.
Similarly, clusters C2 and C10 with a thrust affinity can generate earthquakes of
maximum magnitude Mw 7.9 and 8.2, whereas C8 and C9 may generate earthquakes
of Mw 7.6 and 8.2, respectively.
6. Conclusions
The seismicity map and its correlation to crustal and mantle faults for the BAAS and
WSA are given in this study. For this, only 1752 events of mb ¼ 5.0 and above are
selected, using frequency–magnitude relationships, from an earthquake catalogue of
13,057 events, spread over more than a century. The selected events constitute barely
14% of the entire dataset. A cluster analysis using the methodology discussed in this
study brings out 13 clusters distributed in different segments of the arc system.
Nearly half the earthquake population below the arc is actually confined to these
clusters that have a linear fractal geometry consistent with the traces of seismogenic
surfaces. Correlation of clusters to seismological depth sections and the result
derived from 518 CMT solutions of earthquakes reveals details on the distribution of
stress axes, their variation between the individual clusters and the corresponding
faulting pattern. With the exception of the back-arc seismicity (clusters C7 and C8),
the clusters correspond closely with the thrust planes under the fore-arc. Epicentres
in clusters are much shallower, only 50 km (except C2 and C3), for BAAS and within
100 km for WSA. Moreover, the cluster in the western part (C12) of WSA is of a
shallower depth of 30–40 km. This is interesting and important because clustering of
seismicity is confined in both plates: the subducting Indian plate and the overriding
Burmese/SE Asian plate. These results provide a composite three-dimensional
perspective on the stress distribution between the clustered seismic zones of the arc
and their relationship to focal depths. We have argued elsewhere that a nascent rift
around 88 N latitude skirting the Sewell Seamount in south Andaman Sea shows up
as a conspicuous seismic zone (Mukhopadhyay and Dasgupta 2008, Mukhopadhyay
et al. 2010) (figure 4). It is interesting to note that this is situated near the present
Cluster 9 in front of the Andaman subduction zone. The seismic potentiality of the
clusters reveals that clusters C2, C8, C9, C10 and C13 may generate earthquakes
varying from Mw 7.6 to 8.8.
Acknowledgements
The authors are grateful to the two reviewers for their comments/suggestions which
have helped to improve the earlier version of the manuscript.
References
ANSARI, A., NOORZAD, A. and ZAFARANI, H., 2009, Clustering analysis of the seismic catalog of
Iran. Computers & Geosciences, 35, pp. 475–486.
BANERJEE, P., POLLITZ, F., NAGARAJAN, B. and BÜRGMANN, R., 2007, Coseismic slip
distributions of the 26 December 2004 Sumatra–Andaman and 28 March 2005 Nias
earthquakes from GPS static offsets. Bulletin of the Seismological Society of America,
97, pp. S86–S102.
BERTRAND, G. and RANGIN, C.. 2003, Tectonics of the western margin of the Shan plateau
(central Myanmar): implication for the India-Indochina oblique convergence since the
Oligocene. Journal South Asian Earth Science, 21, pp. 1139–1157.
BILEK, S.L., 2007, Using earthquake source durations along the Sumatra–Andaman
subduction system to examine fault zone variations. Bulletin of the Seismological
Society of America, 97, pp. S62–S70.
CHENG, Q., 1999, The gliding box method for multifractal modeling. Computer Geoscience, 25,
pp. 1073–1079.
CURRAY, J.R., EMMEL, F.J., MOORE, D.G. and RAITT, R.W., 1982, Structure, tectonics and
geological history of the northeast Andaman Ocean. In A.E.M. NAIRN, F.G. STEHLI and
S. UEYDA (Eds), The Ocean Basins and Margins, 6, pp. 399–450 (New York: Plenum).
CURRAY, J.R., MOORE, D.G., LAWVER, L.A., EMMEL, F.J., RAITT, R.W., HENRY, M. and
KIECKHEFER, R., 1979, Tectonics of the Andaman Sea and Burma. American
Association of Petroleum Geologists Bulletin, 29, pp. 189–198.
DASGUPTA, S., MUKHOPADHYAY, M., BHATTACHARYA, A. and JANA, T.K., 2003, The geometry
of the Burmese–Andaman subducting lithosphere. Journal of Seismology, 7, pp. 155–
174.
DEMETS, C.R.G., GORDON, G.F., ARGUS, D.F. and STEIN, S., 1990, Current plate motions.
Geophysics Journal International, 101, pp. 425–478.
DEWEY, J.W., CHOY, G., PRESGRAVE, B., SIPKIN, S., TARR, A.C., BENZ, H., EARLE, P. and WALD,
D., 2007, Seismicity associated with the Sumatra–Andaman Islands earthquake of
December 26, 2004. Bulletin of the Seismological Society of America, 97, pp. S25–S42.
ENGDAHL, E.R., VILLASEÑOR, A., DESHON, H.R. and THURBER, C.H., 2007, Teleseismic
relocation and assessment of seismicity (1918–2005) in the region of the 2004 Mw 9.0
Sumatra–Andaman and 2005 Mw 8.6 Nias Island great earthquakes. Bulletin of the
Seismological Society of America, 97, pp. S43–S61.
FAENZA, L., HAINZI, S., SCHERBAUM, F. and BEAUVAL, C., 2007, Statistical analysis of time-
dependent earthquake occurrence and its impact on hazard in the low seismicity region
Lower Rhine Embayment. Geophysics Journal International, 171, pp. 797–806.
FEEDER, J., 1988, Fractals (New York: Plenum Press).
FRANKE, D., SCHNABEL, M., LADAGE, S., TAPPIN, D.R., NEBEN, S., DJAJADIHDJA, Y.S., MÜLLER,
C., KOPP, H. and GAEDICKE, C., 2008, The great Sumatra–Andaman earthquakes –
Imaging the boundary between the ruptures of the great 2004 and 2005 earthquakes.
Earth and Planetary Science Letters, 269, pp. 118–130.
FUJII, Y. and SATAKE, K., 2007, Tsunami source of the 2004 Sumatra–Andaman earthquake
inferred from tide gauge and satellite data. Bulletin of the Seismological Society of
America, 97, pp. S192–S207.
GAHALAUT, V.K., SUBRAHMANYAM, C., KUNDU, B., CATHERINE, J.K. and AMBIKAPATHY, A.,
2010, Slow rupture in Andaman during 2004 Sumatra–Andaman earthquake: a
probable consequence of subduction of 908 E ridge. Geophysical Journal International,
180, pp. 1181–1186.
HÉBERT, H., SLADEN, A. and SCHINDELÉ, F., 2007, Numerical modeling of the great 2004
Indian Ocean tsunami: focus on the Mascarene Islands. Bulletin of the Seismological
Society of America, 97, pp. S208–S222.
HILL, D.P., 1977, A model of earthquake swarms. Journal Geophysical Research, 82, pp. 1347–
1352.
KAGAN, Y.Y. and JACKSON, D.D., 1991, Long-term earthquake clustering. Geophysical Journal
International, 104, pp. 117–134.
LE DAIN, A.Y., TAPPONNIER, P. and MOLNAR, P., 1984, Active faulting and tectonics of Burma
and surrounding regions. Journal Geophysical Research, 89, pp. 453–472.
MISHRA, O.P., KAYAL, J.R., CHAKROBORTY, G.K., SINGH, O.P. and GHOSH, D., 2007,
Aftershock investigation in the Andaman–Nicober Islands of India and its tectonic
implications. Bulletin of the Seismological Society of America, 97, pp. S71–S85.
MONECKE, K., FINGER, W., KLARER, D., KONGKO, W., MCADOO, B.G., MOORE, A.L. and
SUDRAJAT, S.U., 2008, A 1,000-year sediment record of tsunami recurrence in northern
Sumatra. Nature, 455, pp. 1232–1234.
MUKHOPADHYAY, B., ACHARYYA, A., MUKHOPADHYAY, M. and DASGUPTA, S., 2010, Relation-
ship between earthquake swarm, rifting history, magmatism and pore pressure
diffusion – an example from South Andaman Sea, India. Journal of The Geological
Society of India, 76, pp. 164–170.
MUKHOPADHYAY, B. and DASGUPTA, S., 2008, Swarms in Andaman Sea, India – a
seismotectonic analysis. Acta Geophysica, 56, pp. 1000–1014.
MUKHOPADHYAY, M., 1984, Seismotectonic of subduction and back-arc rifting under the
Andaman Sea. Tectonophysics, 108, pp. 229–239.
PAUL, J., BURGMANN, R., GAUR, V.K., BILHAM, R., LARSON, K.M., ANANDA, M.B., JADE, S.,
MUKUL, M., ANUPAMA, T.S., SATYAL, G. and KUMAR, D., 2001, The motion and active
deformation of India. Geophysical Research Letter, 28, pp. 647–651.
RHIE, J., DREGER, D., BÜRGMANN, R. and ROMANOWICZ, B., 2007, Slip of the 2004 Sumatra–
Andaman earthquake from joint inversion of long period global seismic waveforms
and GPS static offsets. Bulletin of the Seismological Society of America, 97, pp. S115–
S127.
SHAPIRO, N.M., RITZWOLLER, M.H. and ENGDAHL, E.R., 2008, Structural context of the great
Sumatra–Andaman Island Earthquake. Geophysical Research Letter, 35, L05301.
SIEH, K. and NATAWIDJAJA, D., 2000, Neotectonics of Sumatra fault, Indonesia. Journal of
Geophysical Research, 105, pp. 295–326.
STEIN, S. and OKAL, E.A., 2007, Ultralong period seismic study of the December 2004 Indian
Ocean earthquake and implications for regional tectonics and the subduction process.
Bulletin of the Seismological Society of America, 97, pp. S279–S295.
STORK, A.L., SELBY, N.D., HEYBURN, R. and SEARLE, M.P., 2008, Accurate Relative
Earthquake Hypocenters Reveal Structure of the Burma Subduction Zone. Bulletin
of the Seismological Society of America, 98, pp. 2815–282.
SUBARYA, C., CHLIEH, M., PRAWIRODIRDJO, L., AVOUAC, J.P., BOCK, Y., SIEH, K., MELTZNER,
A.J., NATAWIDJAJA, D.H. and MCCAFFREY, R., 2006, Plate-boundary deformation
associated with the great Sumatra–Andaman earthquake. Nature, 440, pp. 46–51.
TURCOTTE, D.L., 1997, Fractals and Chaos in Geology and Geophysics (Cambridge: Cambridge
University Press).
WELLS, D.L. and COPPERSMITH, K.J., 1994, New empirical relationships among magnitude,
rupture length, rupture width, rupture area and surface displacement. Bulletin of the
Seismological Society of America, 84, pp. 974–1002.

Seismic Cluster Analysis From Burma-Andaman - West Sunda Arc

Uploaded by

Document Information

Original Title

Copyright

Available Formats

Share this document

Share or Embed Document

Sharing Options

Did you find this document useful?

Is this content inappropriate?

Copyright:

Available Formats

Seismic Cluster Analysis From Burma-Andaman - West Sunda Arc

Uploaded by

Copyright:

Available Formats

This article was downloaded by: [Mukhopadhyay, Basab]

On: 13 September 2010

Geomatics, Natural Hazards and Risk

First published on: 13 September 2010

PLEASE SCROLL DOWN FOR ARTICLE

Full terms and conditions of use: http://www.informaworld.com/terms-and-conditions-of-access.pdf

BASAB MUKHOPADHYAY*{, M. FNAIS{, MANOJ MUKHOPADHYAY{

(Received 13 April 2010; in ﬁnal form 3 May 2010)

*Corresponding author. Email: basabmukhopadhyay@yahoo.com

2. Seismic data treatment and analysis

Earthquake magnitude (mb) range Number

dimension 1.059, whereas the non-clustered seismicity designates a point

analogous to the traces of major seismogenic surfaces represented as a

3. Discussion on cluster characteristics

Table 2. Earthquake parameters deﬁning the clusters.

Number of Range of Depth Length of major

Burma. C3 is a north-trending elliptical cluster located south of C2 in the same

3.2 Andaman Arc Clusters

3.3 West Sunda Arc Clusters

instrumental data coverage, in particular, for smaller magnitude earthquakes. A

4. Stress distributions and strain partitioning within seismic clusters

4.1 Burmese Arc Clusters: C1–C3

4.2 Andaman Arc Clusters: C4–C8

Map (refer ﬁgs 6a–8a)

B 738 328 N 158 2268 N 3258 N 308 E 1318 N 618 SW

4.3 South Andaman Sea Cluster C9

4.4 Oﬀshore Sumatra Clusters: C10–C13

5. Seismic potentiality of the large clusters

You might also like