TITLE:
Intraplate Strike-Slip Reactivation of the Sinnyeong Fault in the Cretaceous Gyeongsang Basin, Korea, Due to the Concentration of Later Compressional Stress
AUTHORS:
Youngbeom Cheon, Cheol Woo Song, Son Kap Lee, Jong-Sun Kim, Moon Son
KEYWORDS:
Sinnyeong Fault; Sinistral-Reverse Oblique-Slip; Compressional Stress; Pre-Existing Fault
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.1 No.3,
November
29,
2013
ABSTRACT: This study focuses on the geometry and
kinematics of the Sinnyeong Fault which is the most conspicuous fault among the
WNW-trending Gaeum Fault System in the Gyeongsang Basin,SE Korea.
The fault is traced for over ca.70 kmand has a consistent WNW-trending strike with a nearly vertical dip. It has an
asymmetric fault damage zone of several meters to several tens of meters in
width and a several meter-thick
fault core. Its main movement is interpreted as sinistral-reverse oblique-slip
or sinistral strike-slip under NE-SW compressional stress regime, although it could
have experienced other faultings with different senses before/after this movement. Cylindrical
folds, having the NW-trending fold axes of low angle plunge, are only observed along the southern damage
zone of the fault with a continuous narrow width of several tens of meters. It
is thus interpreted that the formation of the folds and sinistral movement of
the fault were almost contemporaneously generated due to the concentration of
the regional NE-SW compressional
stress along pre-existing WNW-trending faults or densely populated fracture
zone in a relatively stable
intraplate region.