Impact of The 2004 Sumatra-Andaman Earthquake to The Stress Heterogeneity and Seismicity Pattern in Nothern Sumatra, Indonesia

2nd Southeast Asian Conference on Geophysics

Taufiq Rafie, Muhammad^1 ; Sahara, David P^2 ; Widiyantoro, Sri^2 ; Dian Nugraha, Andri^2

Master Program of Geophysical Engineering, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Ganesha 10, Bandung

40132, Indonesia^1

Global Geophysics Group, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Ganesha 10, Bandung

40132, Indonesia^2

关键词: Centroid moment tensors;    Instability criterion;    Iterative joints;    Maximum principal stress;    Megathrust earthquakes;    Seismicity pattern;    Sumatra , Indonesia;    Sumatra-Andaman earthquake;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/318/1/012010/pdf
DOI  :  10.1088/1755-1315/318/1/012010

来源: IOP

【 摘 要 】

Sumatra Island is a highly seismic active region due to its close location to the convergent zone between the Indo-Australian and Eurasian plates, and the existence of the Great Sumatran Fault (GSF). These conditions caused the island of Sumatra suffered from hundreds of earthquakes with Mw > 4 per year. Particularly, a 9.0 Mw Sumatra-Andaman 2004 earthquake occured in northern Sumatra which changed the in-situ stress and seismicity pattern. In such case, quantifying the tectonic stress perturbation prior and after 2004 Sumatra-Andaman earthquake is becoming key issue in assessing the seismic hazard. To invert the in-situ stress information in Sumatra, first we identify the fault plane from its auxiliary plane in the focal mechanism solutions using the fault instability criterion. There are 354 focal mechanisms data of earthquake with Mw > 5 and focal depths