Unveiling the Mechanisms of the 1819 M 7.7 Kachchh Earthquake, India: Integrating Physics-Based Simulation and Strong Ground Motion Estimates

Sunilkumar, T. C.1; Zhang, Zhenguo1,2; Wang, Zijia1; Wang, Wenqiang1; He, Zhongqiu1

2024-08-01

10.1029/2023EA003308

EARTH AND SPACE SCIENCE   影响因子和分区

2333-5084

["This study provided a comprehensive understanding of the source process of the 1819 M 7.7 Kachchh Indian earthquake using physics-based dynamic rupture modeling and strong ground motion simulations. We successfully simulated the spontaneous dynamic rupture along a curved non-planar fault using the 3-D curved-grid finite-difference method (CGFDM). The estimated earthquake magnitude is around 7.6, consistent with previous estimations. Our simulations accurately replicated macroscopic rupture patterns and surface deformation, showing agreement with observed data along the Allah Bund fault (ABF) with a maximum displacement similar to 5.5 m at the Earth's surface. The maximum modeled coseismic slip on the fault was approximately 7.5 m. Notably, the ABF exhibited characteristics of a weak barrier (leaky barrier) at the bending part, allowing the rupture to propagate further. Despite limitations in surface deformation calculations, the modeled values aligned with the trend of surface fault slip, with a slight deviation in the epicenter toward the east compared to earlier studies. We observed a homogeneous principal stress oriented N25 degrees E, consistent with the present day Indian plate motion. The estimated horizontal peak ground velocities (PGVh) and the maximum value of Intensity X+ aligns well with observations. Furthermore, conducting thorough case studies on significant earthquakes and potential seismic scenarios in stable continental regions is crucial. Such studies play a vital role in validating and improving dynamic rupture models. When combined with statistical methods, this research holds great promise for advancing seismic hazard assessments, earthquake engineering, and strategies for disaster management.","This paper is centered around the simulation of the dynamic rupture of the 1819 M 7.7 Kachchh earthquake in India. We have successfully replicated the earthquake's behavior using a three-dimensional simulation method. The study's results demonstrate the significant influence of the local tectonic setting and non-planar fault structure on earthquake generation and rupture progression. Although slight discrepancies exist between the simulation results and actual observations, the simulations capture significant trends and reproduce macroscopic rupture patterns. The estimated magnitude of the earthquake aligns well with previous studies. The study highlights the role of fault bending and its impact on surface deformation, contributing to a better understanding of seismic hazards and providing insights for seismic hazard assessments and earthquake source characterization. This work is valuable for comprehending earthquake sources, particularly from earthquake perspectives in the SCR region and other areas.","Dynamic rupture simulations of the 1819 Kachchh M 7.7 earthquake replicate co-seismic fault slip, enhance our knowledge of the earthquake source Weak barrier characteristics observed at the bending part of the fault enabled further rupturing, influenced by SH and the nucleation point Contributes to understanding earthquake hazards, enhancing seismic assessment, engineering, and disaster management strategies"]

earthquake simulation rupture dynamics ground motion seismic hazard assessment

SCI

英语

第一 ; 通讯

Guangdong Provincial Key Laboratory of Geophysical High-resolution Image Technology[42174057] ; National Natural Science Foundation of China[2022B1212010002] ; Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology[GML2019ZD0203] ; Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou)[KQTD20170810111725321] ; Shenzhen Science and Technology Program[G03050K001]

Astronomy & Astrophysics ; Geology

Astronomy & Astrophysics ; Geosciences, Multidisciplinary

WOS:001292574400001

AMER GEOPHYSICAL UNION

Web of Science

1.Southern Univ Sci & Technol, Dept Earth & Space Sci, Shenzhen, Peoples R China
2.Southern Univ Sci & Technol, Guangdong Prov Key Lab Geophys High Resolut Imagin, Shenzhen, Peoples R China

Sunilkumar, T. C.,Zhang, Zhenguo,Wang, Zijia,et al. Unveiling the Mechanisms of the 1819 M 7.7 Kachchh Earthquake, India: Integrating Physics-Based Simulation and Strong Ground Motion Estimates[J]. EARTH AND SPACE SCIENCE,2024,11(8).

Sunilkumar, T. C.,Zhang, Zhenguo,Wang, Zijia,Wang, Wenqiang,&He, Zhongqiu.(2024).Unveiling the Mechanisms of the 1819 M 7.7 Kachchh Earthquake, India: Integrating Physics-Based Simulation and Strong Ground Motion Estimates.EARTH AND SPACE SCIENCE,11(8).

Sunilkumar, T. C.,et al."Unveiling the Mechanisms of the 1819 M 7.7 Kachchh Earthquake, India: Integrating Physics-Based Simulation and Strong Ground Motion Estimates".EARTH AND SPACE SCIENCE 11.8(2024).