Search

We have conducted geoelectric resistivity and shear wave velocity (Vs30) study to identify the landslide potential hazard, around Geophysics Station Lembang, Bandung (107,617∘ E and 6,825∘ S). The the geoelectric analysis using Dipole-Dipole resitivity configuration, while shear wave velocity analysis performed using the Multichannel Analysis of Surface Wave (MASW). The study results indicate that the assumed soil or clay depth from the electrical resistivity observation was in accordance with the confirmed soil or clay depth by the MASW investigation. Based on these conditions, indicate the high potential of landsliding in this area, landslide potential supported by high slope angle in this area. [ABSTRACT FROM AUTHOR]

A geophysic survey is performed to detect subsurface structure under STMKG Campus in Pondok Betung, South Tangerang, Indonesia, using seismic refraction method. The survey used PASI 16S24-U24. The waveform data is acquired from 3 different tracks on the research location with a close range from each track. On each track we expanded 24 geofons with spacing between receiver 2 meters and the total length of each track about 48 meters. The waveform data analysed using 2 different ways. First, used a seismic refractionapplication WINSISIM 12 and second, used a Hagiwara Method. From both analysis, we known the velocity of P-wave in the first and second layer and the thickness of the first layer. From the velocity and the thickness informations we made 2-D vertical subsurface profiles. In this research, we only detect 2 layers in each tracks. The P-wave velocity of first layer is about 200-500 m/s with the thickness of this layer about 3-6 m/s. The P-wave velocity of second layer is about 400-900 m/s. From the P-wave velocity data we interpreted that both layer consisted by similar materials such as top soil, soil, sand, unsaturated gravel, alluvium and clay. But, the P-wave velocity difference between those 2 layers assumed happening because the first layer is soil embankment layer, having younger age than the layer below. [ABSTRACT FROM AUTHOR]