Seismic Travel-time Tomography beneath Merapi Volcano and its Surroundings: A Preliminary Result from DOMERAPI Project

Southeast Asian Conference on Geophysics

Ramdhan, Mohamad^1,2 ; Widiyantoro, Sri^3 ; Dian Nugraha, Andri^3 ; Saepuloh, Asep^3 ; Métaxian, Jean-Philippe^4 ; Kristyawan, Said^1,2 ; Syaly Sembiring, Andry^1,2 ; Budi Santoso, Agus^5

Graduate Program of Earth Sciences, Faculty of Earth Sciences and Technology, Institut Teknologi Bandung, Indonesia^1

Agency for Meteorology, Climatology and Geophysics (BMKG), Indonesia^2

Global Geophysical Research Group, Faculty of Mining and Petroleum Engineering, Institut Teknologi Bandung, Indonesia^3

ISTerre, IRD R219, CNRS, Universit'e de Savoie, Le Bourget-du-Lac, France^4

Center for Research and Technology Development of Geological Disaster (BPPTKG), Indonesia, Indonesia^5

关键词: DOMERAPI;    Geophysical methods;    Hypocenter location;    Low velocities;    Merapi;    Seismic tomographic imaging;    Seismic tomography;    Seismic travel time;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/62/1/012039/pdf
DOI  :  10.1088/1755-1315/62/1/012039

来源: IOP

【 摘 要 】

Many geophysical methods at various scales have been applied to understand the internal structure beneath Merapi volcano and its magmatic process. As part of the DOMERAPI project, a seismic experiment was conducted from October 2013 to mid April 2015 in order to determine the deep magma source beneath the volcano through seismic travel-time tomography. The earthquake events were identified and picked manually and carefully to determine the hypocenters. They were then relocated to get precise hypocenter locations before running the seismic tomographic imaging. The data from the BMKG network from the same period of time as mentioned above were also incorporated to minimize azimuthal gap, because the majority of events occurred outside the DOMERAPI network. The checkerboard resolution test result depicts that the area around the network can be well resolved. Compared to previous studies, our result shows a higher resolution at shallow depths, i.e., less than 35 km and a low velocity material imaged to ascend diagonally from the deeper area.