| Summary: | Conducted research on the identification of active fault pathways in
Semangko segment, subsegment Suoh-Kotaagung, Lampung region, Sumatera.
Georadar method with radar reflection profiling configuration and geoelectrical
method with dipole-dipole configuration have been used in this research to
determine the existence of fault pathways and the outlook subsurface structure
which potentially indicate earthquake in this area. This research was conducted
in 17 lines measurement divided to 4 subsegment of 10 subsegment in Kotaagung
area, such as Asahan subsegment (2 lines), Sedayu subsegment (7 lines),
Semangka subsegment (3 lines) and Kotaagung subsegment (5 lines).
Reflexwave software has been used in georadar data processing obtained
from the result of GSSI surveyor 20 measurement. There are five steps to process
the data measurement, automatic gain control, static correction, bandpass filter,
background removal, and migration to eliminate noise from the data in order to
obtain radargram section. In addition, Earthimager 2DINV software has been
used in geoelectrical processing data from the measurement of multichannel
supersting R8. Inversion from apparent resistivity to actual resistivity has been
conducted in this software used to interpret subsurface section in the research
area.
Identified fault pathways in this research have been indicated by line 3, 4,
5, and 6 in the sedayu subsegment, line 7 and 15 in Asahan subsegment, line 8, 9,
and 14 in Kotaagung subsegment. The existence of fault subsegment were
detected at shallow depth about 5-58 meter below surface area potentially
indicate destructive earthquakes in the research area. Kotaagung subsurface
structure is arranged by quartenary sediment, Sandy clay (0.1-80 �m), and sand
(100-500 �m) that is separated by granite intrusion (600-100.000 �m) indicating
fault pathways
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