HR: 0804h
AN: NS11E-0830 [Abstracts]
TI: The Characteristics of Shallow Seismic Reflection Images Across a Fault Between Slate and Conglomerate
AU: * Wang, L
EM: apg5025@eq.ccu.edu.tw
AF: National Chung Cheng University, 168 University Rd.,Minhsiung, Chiayi, TW 621, Taiwan
AU: Shih, R
EM: seirock@eq.ccu.edu.tw
AF: National Chung Cheng University, 168 University Rd.,Minhsiung, Chiayi, TW 621, Taiwan
AU: Lin, C
AF: Central Geological Survey, No.2,Lane 109,Huasin St.,Jhonghe, Taipei, TW 235, Taiwan
AB:
The Taitung Longitudinal Valley in eastern Taiwan is the suture zone of the Eurasian and Philippine Sea plates.
The valley is bound by the Central Mountain Range and the Coastal Range to the west and east, respectively.
Because of rapid uplifting of the Central Mountain Range, there are series of terraces and alluvial fans existed
along the eastern foothill of the Central Mountain Range. The Luyeh terrace is one of the terraces, which consists
of a flexure scarp caused by the reactivation of the Luyeh fault. The Luyeh fault is a major active faults situated in
the western margin of the of the suture zone. The fault is a reverse-slip fault and shows a clear lineament striking
from north to south from geomorphic investigation. The Luyeh fault basically separates the slate formation of the
Central Mountain Range from the conglomerate of the Luyeh terrace at shallow depth. Several investigations have
been conducted to show the structural characteristics of the Luyeh fault; however, none direct contact of the fault
was seen. Although seismic reflection method was thought inappropriate for applying over slate formations, the
contact of slates and fluvial deposits sometimes becomes a remarkable boundary for mapping. We have
conducted several shallow seismic reflection lines to delineate the Luyeh fault. Although the seismic lines were
deployed on a difficult terrain across slate formations and conglomerate, the characteristics of shallow seismic
reflection images show the eastward dipping Luyeh fault, its possible locations and the branches.
DE: 7200 SEISMOLOGY
DE: 8010 Fractures and faults
DE: 8015 Local crustal structure
SC: Near-Surface Geophysics [NS]
MN: 2007 Fall Meeting