CoCCooCo ----seismic Displacement of 24 ----March ----2011 Mw...
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Co Co Co Co- seismic Displacement of 24 seismic Displacement of 24 seismic Displacement of 24 seismic Displacement of 24- March March March March-2011 Mw 6.8 Tarlay 2011 Mw 6.8 Tarlay 2011 Mw 6.8 Tarlay 2011 Mw 6.8 Tarlay Co Co Co Co- seismic Displacement of 24 seismic Displacement of 24 seismic Displacement of 24 seismic Displacement of 24- March March March March-2011 Mw 6.8 Tarlay 2011 Mw 6.8 Tarlay 2011 Mw 6.8 Tarlay 2011 Mw 6.8 Tarlay (Mong Hpayak) Earthquake, Myanmar (Mong Hpayak) Earthquake, Myanmar (Mong Hpayak) Earthquake, Myanmar (Mong Hpayak) Earthquake, Myanmar Itthi Trisirisatayawong 1 , Andy Hooper 2 , Anuphao Aobpaet 3 1 Department of Survey Engineering, Chulalongkorn University, Thailand 1 Department of Survey Engineering, Chulalongkorn University, Thailand 2 Department of Remote Sensing, Delft University of Technology, Netherlands 3 Geo-Informatic and Space Technology Development Agency, Thailand. 3 Geo-Informatic and Space Technology Development Agency, Thailand. INTRODUCTION INTRODUCTION INTRODUCTION INTRODUCTION COULOMB STRESS CHANGE COULOMB STRESS CHANGE COULOMB STRESS CHANGE COULOMB STRESS CHANGE INTRODUCTION INTRODUCTION INTRODUCTION INTRODUCTION The March 2011 Mw 6.8 Mong COULOMB STRESS CHANGE COULOMB STRESS CHANGE COULOMB STRESS CHANGE COULOMB STRESS CHANGE The parameters of ruptured segment of Nam Ma fault obtained Hpayak earthquake occurred on the western segment of the Nam Ma fault, one of many left-lateral segment of Nam Ma fault obtained from inversion analysis are used in the computation of Coulomb Ma fault, one of many left-lateral faults in the border region of Myanmar, Laos and Thailand. SAR in the computation of Coulomb stress change. We use USGS Coulomb program for this Myanmar, Laos and Thailand. SAR images are probably the only available geodetic data for studying the co-seismic motion of this computation. The stress change is resolved on segments of Mae Chan fault (left-lateral) in northern the co-seismic motion of this earthquake. Two-pass DInSAR processing of both ascending and Chan fault (left-lateral) in northern Thailand and also on a thrust fault in between Nam Ma and Mae processing of both ascending and descending ALOS radar images reveals surface displacement Figure 2. Interferogram from ascending (left) and descending SAR image pair. Each fringe, from a color strip to the next one, represents half- wavelength (12.8 cm) diisplacement in radar line-of- in between Nam Ma and Mae Chan. reveals surface displacement pattern of nearly pure strike-slip fault. These InSAR results are modeled as elastic response to slip wavelength (12.8 cm) diisplacement in radar line-of- sight direction INVERSION RESULTS INVERSION RESULTS INVERSION RESULTS INVERSION RESULTS modeled as elastic response to slip on a planar fault and then down sampled for the inversion to solve INVERSION RESULTS INVERSION RESULTS INVERSION RESULTS INVERSION RESULTS The resulted model characterize the Nam Ma fault as near vertical, sampled for the inversion to solve for fault parameters. The co- seismic displacements predicted by the Nam Ma fault as near vertical, almost pure strike-slip. The slip is 2.5 m, and the computed moment the resulted fault model agrees well with InSAR observations. We then calculate the distribution of magnitude from the model is Mw- 6.75 which is similar to the one determined by seismometers. calculate the distribution of Coulomb stress change in nearby active faults and it is revealed that determined by seismometers. The solution model from inversion is used to generate modeled co- Figure 4.Coulomb stress change on segments of Mae Chan fault and a thrust fault. active faults and it is revealed that certain sections of Mae Chan fault in Chiengrai, northern Thailand, have increasing stress. This is used to generate modeled co- seismic motion in radar line-of- sight and the differences are computed. These are shown in Mae Chan fault and a thrust fault. CONCLUSION CONCLUSION CONCLUSION CONCLUSION have increasing stress. This information would help re-evaluate the likelihood of future earthquake computed. These are shown in Fig. 3. CONCLUSION CONCLUSION CONCLUSION CONCLUSION L-band radar images have proved to be valuable data to determine the likelihood of future earthquake in this fault zone. to be valuable data to determine surface co-seismic displacement of the Nam Ma earthquake. The computed deformations from computed deformations from InSAR are used as constraints in the inversion analysis of fault the inversion analysis of fault parameters using simple fault plane model which subsequently plane model which subsequently be used to compute Coulomb stress changes in nearby faults. We found that middle segments of We found that middle segments of Mae Chan fault fall in stress shadow and so inhibits Coulomb Figure 1. Location map of Nam Ma and Mae Chan fault. Fault lines of Nam Ma and a small unnamed are approximated from graphic in shadow and so inhibits Coulomb failure. On the northern part of the other reverse fault passing http://www.earthobservatory.sg/media/news-and- features/295-myanmar-earthquake-of-march-24th- magnitude-68.html. Earthquake epicenters are from USGS reports. Figure 3. (above row) Coseismic displacement in line of sight of ascending ALOS path from the down through Mae Sai and Tachilek, Coulomb stress increase by 0.15 bar. This may indicate that the USGS reports. line of sight of ascending ALOS path from the down sampled interferogram (left), model (middle) and the residual between the two (right). The images in below row are from descending path.. bar. This may indicate that the eastern and northern tip of these two faults may have higher DATA DATA DATA DATA Both ascending and descending ACKNOWLEDGMENTS ACKNOWLEDGMENTS ACKNOWLEDGMENTS ACKNOWLEDGMENTS two faults may have higher probability of seismic hazard. Both ascending and descending ALOS PALSAR SLC (single look complex) radar images with precision orbit and standard ACKNOWLEDGMENTS ACKNOWLEDGMENTS ACKNOWLEDGMENTS ACKNOWLEDGMENTS The authors would like to thank Sentinel Asia for the provision of ALOS PALSAR images for this study. We thank Dr. Anond Snidvong, GISTDA director and also GISTDA staff at precision orbit and standard attitude data spanning the period of mid-February and early April for this study. We thank Dr. Anond Snidvong, GISTDA director and also GISTDA staff at the KMIT receiving station for coordinating with JAXA and for the rapid delivery of the images. The inversion analysis program is developed by Andy Hooper, Delft University of of mid-February and early April 2011 were obtained through Sentinel Asia. Technology, Netherlands. The study is part of the GEO2TECDI-SONG project under the Thailand-EU Cooperation Facility II funding scheme whose support is gratefully acknowledged here. Sentinel Asia. acknowledged here.
Transcript of CoCCooCo ----seismic Displacement of 24 ----March ----2011 Mw...
CoCoCoCo----seismic Displacement of 24seismic Displacement of 24seismic Displacement of 24seismic Displacement of 24----MarchMarchMarchMarch----2011 Mw 6.8 Tarlay 2011 Mw 6.8 Tarlay 2011 Mw 6.8 Tarlay 2011 Mw 6.8 Tarlay CoCoCoCo----seismic Displacement of 24seismic Displacement of 24seismic Displacement of 24seismic Displacement of 24----MarchMarchMarchMarch----2011 Mw 6.8 Tarlay 2011 Mw 6.8 Tarlay 2011 Mw 6.8 Tarlay 2011 Mw 6.8 Tarlay (Mong Hpayak) Earthquake, Myanmar(Mong Hpayak) Earthquake, Myanmar(Mong Hpayak) Earthquake, Myanmar(Mong Hpayak) Earthquake, Myanmar(Mong Hpayak) Earthquake, Myanmar(Mong Hpayak) Earthquake, Myanmar(Mong Hpayak) Earthquake, Myanmar(Mong Hpayak) Earthquake, MyanmarItthi Trisirisatayawong1, Andy Hooper2, Anuphao Aobpaet3
1Department of Survey Engineering, Chulalongkorn University, Thailand1Department of Survey Engineering, Chulalongkorn University, Thailand2 Department of Remote Sensing, Delft University of Technology, Netherlands
3 Geo-Informatic and Space Technology Development Agency, Thailand.3 Geo-Informatic and Space Technology Development Agency, Thailand.
INTRODUCTIONINTRODUCTIONINTRODUCTIONINTRODUCTION COULOMB STRESS CHANGECOULOMB STRESS CHANGECOULOMB STRESS CHANGECOULOMB STRESS CHANGEINTRODUCTIONINTRODUCTIONINTRODUCTIONINTRODUCTION
The March 2011 Mw 6.8 Mong
COULOMB STRESS CHANGECOULOMB STRESS CHANGECOULOMB STRESS CHANGECOULOMB STRESS CHANGEThe parameters of ruptured segment of Nam Ma fault obtained
The March 2011 Mw 6.8 MongHpayak earthquake occurred onthe western segment of the NamMa fault, one of many left-lateral
segment of Nam Ma fault obtained from inversion analysis are used in the computation of Coulomb Ma fault, one of many left-lateral
faults in the border region ofMyanmar, Laos and Thailand. SAR
in the computation of Coulomb stress change. We use USGS Coulomb program for this computation. The stress change is
Myanmar, Laos and Thailand. SARimages are probably the onlyavailable geodetic data for studyingthe co-seismic motion of this
Coulomb program for this computation. The stress change is resolved on segments of Mae Chan fault (left-lateral) in northern
available geodetic data for studyingthe co-seismic motion of thisearthquake. Two-pass DInSARprocessing of both ascending and
Chan fault (left-lateral) in northern Thailand and also on a thrust fault in between Nam Ma and Mae processing of both ascending and
descending ALOS radar imagesreveals surface displacement
Figure 2. Interferogram from ascending (left) anddescending SAR image pair. Each fringe, from acolor strip to the next one, represents half-wavelength (12.8 cm) diisplacement in radar line-of-
in between Nam Ma and Mae Chan.
reveals surface displacementpattern of nearly pure strike-slipfault. These InSAR results aremodeled as elastic response to slip
wavelength (12.8 cm) diisplacement in radar line-of-sight direction
INVERSION RESULTSINVERSION RESULTSINVERSION RESULTSINVERSION RESULTSmodeled as elastic response to slipon a planar fault and then downsampled for the inversion to solve
INVERSION RESULTSINVERSION RESULTSINVERSION RESULTSINVERSION RESULTSThe resulted model characterize the Nam Ma fault as near vertical, sampled for the inversion to solve
for fault parameters. The co-seismic displacements predicted bythe resulted fault model agrees well
the Nam Ma fault as near vertical, almost pure strike-slip. The slip is 2.5 m, and the computed moment seismic displacements predicted by
the resulted fault model agrees wellwith InSAR observations. We thencalculate the distribution of
2.5 m, and the computed moment magnitude from the model is Mw-6.75 which is similar to the one determined by seismometers. calculate the distribution of
Coulomb stress change in nearbyactive faults and it is revealed that
determined by seismometers. The solution model from inversion is used to generate modeled co-
Figure 4.Coulomb stress change on segments ofMae Chan fault and a thrust fault.active faults and it is revealed that
certain sections of Mae Chan faultin Chiengrai, northern Thailand,have increasing stress. This
is used to generate modeled co-seismic motion in radar line-of-sight and the differences are computed. These are shown in
Mae Chan fault and a thrust fault.
CONCLUSIONCONCLUSIONCONCLUSIONCONCLUSIONhave increasing stress. Thisinformation would help re-evaluatethe likelihood of future earthquake
computed. These are shown in Fig. 3.
CONCLUSIONCONCLUSIONCONCLUSIONCONCLUSIONL-band radar images have proved to be valuable data to determine the likelihood of future earthquake
in this fault zone.to be valuable data to determine surface co-seismic displacement of the Nam Ma earthquake. The computed deformations from of the Nam Ma earthquake. The computed deformations from InSAR are used as constraints in the inversion analysis of fault the inversion analysis of fault parameters using simple fault plane model which subsequently plane model which subsequently be used to compute Coulomb stress changes in nearby faults. We found that middle segments of We found that middle segments of Mae Chan fault fall in stress shadow and so inhibits Coulomb
Figure 1. Location map of Nam Ma and Mae Chanfault. Fault lines of Nam Ma and a small unnamedare approximated from graphic in
shadow and so inhibits Coulomb failure. On the northern part of the other reverse fault passing through Mae Sai and Tachilek,
are approximated from graphic inhttp://www.earthobservatory.sg/media/news-and-features/295-myanmar-earthquake-of-march-24th-magnitude-68.html. Earthquake epicenters are fromUSGS reports.
Figure 3. (above row) Coseismic displacement inline of sight of ascending ALOS path from the down
other reverse fault passing through Mae Sai and Tachilek, Coulomb stress increase by 0.15 bar. This may indicate that the USGS reports. line of sight of ascending ALOS path from the down
sampled interferogram (left), model (middle) andthe residual between the two (right). The images inbelow row are from descending path..
bar. This may indicate that the eastern and northern tip of these two faults may have higher
DATADATADATADATABoth ascending and descending ACKNOWLEDGMENTSACKNOWLEDGMENTSACKNOWLEDGMENTSACKNOWLEDGMENTS
two faults may have higher probability of seismic hazard.
Both ascending and descending ALOS PALSAR SLC (single look complex) radar images with precision orbit and standard
ACKNOWLEDGMENTSACKNOWLEDGMENTSACKNOWLEDGMENTSACKNOWLEDGMENTSThe authors would like to thank Sentinel Asia for the provision of ALOS PALSAR imagesfor this study. We thank Dr. Anond Snidvong, GISTDA director and also GISTDA staff at
complex) radar images with precision orbit and standard attitude data spanning the period of mid-February and early April
for this study. We thank Dr. Anond Snidvong, GISTDA director and also GISTDA staff atthe KMIT receiving station for coordinating with JAXA and for the rapid delivery of theimages. The inversion analysis program is developed by Andy Hooper, Delft University ofof mid-February and early April
2011 were obtained through Sentinel Asia.
images. The inversion analysis program is developed by Andy Hooper, Delft University ofTechnology, Netherlands. The study is part of the GEO2TECDI-SONG project under theThailand-EU Cooperation Facility II funding scheme whose support is gratefullyacknowledged here.Sentinel Asia. acknowledged here.
