HR: 0800h
AN: T11A-0349    [Abstracts]
TI: Fracture Controlled Dyke Intrusion Patterns And Inferred Stress Conditions In Geo-je Island, Southeast Korea
AU: * Yang, S
EM: rokmcjun927@hanmail.net
AF: Seok-jun Yang, 599-1, Daeyeon3-dong, Nam-gu, Dept. of Environmental Geosciences, Pukyong National University, Busan 608-737, Korea, Busan, 608-737, Korea, Republic of
AU: Kim, Y
EM: ysk7909@pknu.ac.kr
AF: Seok-jun Yang, 599-1, Daeyeon3-dong, Nam-gu, Dept. of Environmental Geosciences, Pukyong National University, Busan 608-737, Korea, Busan, 608-737, Korea, Republic of
AU: Jin, K
EM: maxgarion@nate.com
AF: Seok-jun Yang, 599-1, Daeyeon3-dong, Nam-gu, Dept. of Environmental Geosciences, Pukyong National University, Busan 608-737, Korea, Busan, 608-737, Korea, Republic of
AU: Lee, H
EM: heanu@kins.re.kr
AF: Hyunwoo Lee, Structural Systems and Site Evaluation, Safety Technology Division, Korea Institute of Nuclear Safety Daejeon 305-338, Korea, Daejeon, 305-338, Korea, Republic of
AB: Tertiary basic dykes systematically intruded Cretaceous sedimentary rocks in Geo-je Island, southeast Korea, where a variety of non-planar intrusive patterns are observed. The characteristics of the intrusive patterns are analyzed and classified, and their associated stress conditions are inferred. Based on this kinematic analysis, the relationship between dyke intrusion patterns and fractures development is interpreted. The predominant orientations of the dykes are NNE-SSW and NNW-SSE, which are also consistent in vein and fracture orientations. It means that the dykes intruded along the pre-existing weakness indicating passive intrusion controlled by pre-existing fractures. This relationship is also supported by the fracture analysis based on cross-cutting relationship, restoration of the dyke intrusion gaps, and inferred deformation history in this area. Therefore, dyke intrusion patterns in this study area are mainly controlled by pre-existing fracture patterns as well as stress condition during magma intrusion. This study might be very useful to interpret local tectonic stress changes and origins. Keywords: dyke intrusion patterns, pre-existing fractures, stress condition, passive intrusion, deformation history
DE: 8010 Fractures and faults
DE: 8011 Kinematics of crustal and mantle deformation
DE: 8035 Pluton emplacement
DE: 8178 Tectonics and magmatism
SC: Tectonophysics [T]
MN: 2007 Fall Meeting