Application of seismic refraction method to identify rock layers around the lake body in Jakarta, Indonesia

Abstract The objective of this study was to identify the lithological layer around lake body determine ability reservoir structure withstand surrounding seepage water. This research conducted using MAE X820S seismic instrument, carried out on a 46-meter-long track and 24 geophones. Seismic refraction processing is done by picking at first break in each trace. From results, distance time parameters will be obtained so that velocity model can generated analyzed for types based P-wave velocity. results show area consists two rock layers. range P wave owned depth 0-19 m 648.11 m/s, interpreted as sand-gravel. 19-30 1553.21 clay. Rock layers have sand-gravel lithology seep or pass water, while clay cannot Therefore, thought less strong