Focal mechanism of the August 18th 2012 Mw6.3 Palu-Koro earthquake and its implication of seismic hazard

The Palu-Koro fault is a left-lateral strike-slip fault in Sulawesi within the active triple junction generated by the ongoing fast convergence of the Pacific-Philippine plate, the Indo-Australian plate and the Sunda plate. There are densely populated areas that are susceptible to earthquakes occur...

Full description

Bibliographic Details
Main Authors: Khairina, Fadiah, Chen, Weiwen, Wei, Shengji, Suardi, Iman
Other Authors: International Symposium on Earth Hazard and Disaster Mitigation (ISEDM) 2016
Format: Journal Article
Language:English
Published: 2018
Subjects:
Online Access:https://hdl.handle.net/10356/89081
http://hdl.handle.net/10220/46026
_version_ 1811681062494928896
author Khairina, Fadiah
Chen, Weiwen
Wei, Shengji
Suardi, Iman
author2 International Symposium on Earth Hazard and Disaster Mitigation (ISEDM) 2016
author_facet International Symposium on Earth Hazard and Disaster Mitigation (ISEDM) 2016
Khairina, Fadiah
Chen, Weiwen
Wei, Shengji
Suardi, Iman
author_sort Khairina, Fadiah
collection NTU
description The Palu-Koro fault is a left-lateral strike-slip fault in Sulawesi within the active triple junction generated by the ongoing fast convergence of the Pacific-Philippine plate, the Indo-Australian plate and the Sunda plate. There are densely populated areas that are susceptible to earthquakes occur along the fault, and the August 18th 2012, Mw6.3 earthquake is one of such events. To better understand this earthquake and the seismic hazard in the region, we estimated source parameters of this earthquake using the Cut and Paste (CAP) inversion method with regional broadband waveform data. Our results show that the best solution of this event is 339°, 71°, −16° and 11 km for strike, dip, rake and centroid depth, respectively. Inversions using stations within different distance ranges, i.e. 0-5, 0-10° and 0-20°, reveal consistent solutions, suggesting the robustness of our result, which is also in agreement with that from the other agencies, i.e. USGS and Global CMT. We further verify the centroid depth by modeling the depth phases recorded at the teleseismic distance, which also confirm the depth of 11km. Finally we analyzed the Coulomb stress caused by this earthquake and historical events to investigate the interaction between the earthquakes in the region. Our analysis also shows that the unclamping effect from the 1996 Mw7.9 megathrust in the Minahassa Trench promoted the occurrence of the 2012 Mw6.3 event. High slip-rate across the fault and Coulomb stress analysis suggest that more attention should be paid to the segments along the Palu-Koro fault that did not rupture in the previous earthquake circle.
first_indexed 2024-10-01T03:34:58Z
format Journal Article
id ntu-10356/89081
institution Nanyang Technological University
language English
last_indexed 2024-10-01T03:34:58Z
publishDate 2018
record_format dspace
spelling ntu-10356/890812020-09-26T21:27:07Z Focal mechanism of the August 18th 2012 Mw6.3 Palu-Koro earthquake and its implication of seismic hazard Khairina, Fadiah Chen, Weiwen Wei, Shengji Suardi, Iman International Symposium on Earth Hazard and Disaster Mitigation (ISEDM) 2016 Earth Observatory of Singapore Focal Mechanism Unclamping Effect DRNTU::Science::Geology The Palu-Koro fault is a left-lateral strike-slip fault in Sulawesi within the active triple junction generated by the ongoing fast convergence of the Pacific-Philippine plate, the Indo-Australian plate and the Sunda plate. There are densely populated areas that are susceptible to earthquakes occur along the fault, and the August 18th 2012, Mw6.3 earthquake is one of such events. To better understand this earthquake and the seismic hazard in the region, we estimated source parameters of this earthquake using the Cut and Paste (CAP) inversion method with regional broadband waveform data. Our results show that the best solution of this event is 339°, 71°, −16° and 11 km for strike, dip, rake and centroid depth, respectively. Inversions using stations within different distance ranges, i.e. 0-5, 0-10° and 0-20°, reveal consistent solutions, suggesting the robustness of our result, which is also in agreement with that from the other agencies, i.e. USGS and Global CMT. We further verify the centroid depth by modeling the depth phases recorded at the teleseismic distance, which also confirm the depth of 11km. Finally we analyzed the Coulomb stress caused by this earthquake and historical events to investigate the interaction between the earthquakes in the region. Our analysis also shows that the unclamping effect from the 1996 Mw7.9 megathrust in the Minahassa Trench promoted the occurrence of the 2012 Mw6.3 event. High slip-rate across the fault and Coulomb stress analysis suggest that more attention should be paid to the segments along the Palu-Koro fault that did not rupture in the previous earthquake circle. Published version 2018-09-19T04:41:20Z 2019-12-06T17:17:25Z 2018-09-19T04:41:20Z 2019-12-06T17:17:25Z 2017 Journal Article Khairina, F., Chen, W., Wei, S., & Suardi, I. (2017). Focal mechanism of the August 18th 2012 Mw6.3 Palu-Koro earthquake and its implication of seismic hazard. AIP Conference Proceedings, 1857, 050003-. doi:10.1063/1.4987081 0094-243X https://hdl.handle.net/10356/89081 http://hdl.handle.net/10220/46026 10.1063/1.4987081 en AIP Conference Proceedings © 2017 The Author(s) (Published by AIP). This paper was published in AIP Conference Proceedings and is made available as an electronic reprint (preprint) with permission of the author(s) (published by AIP). The published version is available at: [http://dx.doi.org/10.1063/1.4987081]. One print or electronic copy may be made for personal use only. Systematic or multiple reproduction, distribution to multiple locations via electronic or other means, duplication of any material in this paper for a fee or for commercial purposes, or modification of the content of the paper is prohibited and is subject to penalties under law. 7 p. application/pdf
spellingShingle Focal Mechanism
Unclamping Effect
DRNTU::Science::Geology
Khairina, Fadiah
Chen, Weiwen
Wei, Shengji
Suardi, Iman
Focal mechanism of the August 18th 2012 Mw6.3 Palu-Koro earthquake and its implication of seismic hazard
title Focal mechanism of the August 18th 2012 Mw6.3 Palu-Koro earthquake and its implication of seismic hazard
title_full Focal mechanism of the August 18th 2012 Mw6.3 Palu-Koro earthquake and its implication of seismic hazard
title_fullStr Focal mechanism of the August 18th 2012 Mw6.3 Palu-Koro earthquake and its implication of seismic hazard
title_full_unstemmed Focal mechanism of the August 18th 2012 Mw6.3 Palu-Koro earthquake and its implication of seismic hazard
title_short Focal mechanism of the August 18th 2012 Mw6.3 Palu-Koro earthquake and its implication of seismic hazard
title_sort focal mechanism of the august 18th 2012 mw6 3 palu koro earthquake and its implication of seismic hazard
topic Focal Mechanism
Unclamping Effect
DRNTU::Science::Geology
url https://hdl.handle.net/10356/89081
http://hdl.handle.net/10220/46026
work_keys_str_mv AT khairinafadiah focalmechanismoftheaugust18th2012mw63palukoroearthquakeanditsimplicationofseismichazard
AT chenweiwen focalmechanismoftheaugust18th2012mw63palukoroearthquakeanditsimplicationofseismichazard
AT weishengji focalmechanismoftheaugust18th2012mw63palukoroearthquakeanditsimplicationofseismichazard
AT suardiiman focalmechanismoftheaugust18th2012mw63palukoroearthquakeanditsimplicationofseismichazard