Full-Text Search:
Home|Journal Papers|About CNKI|User Service|FAQ|Contact Us|中文
《Chinese Journal of Geophysics》 2016-09
Add to Favorite Get Latest Update

Thermal modeling of tectonic activity contrast between the south part and the middle and north parts of the Okinawa trough

MENG Lin;ZHANG Xun-Hua;WEN Zhen-He;MENG Xiang-Jun;WANG Ming-Jian;Qingdao Institute of Marine Geology;Laboratory for Marine Mineral Resources,Qingdao National Laboratory for Marine Science and Technology;  
Influenced by the strong back-arc extensional effect along the margin of the Pacific plate in the Cenozoic,the tectonics of the Okinawa trough is very complicated and segmented.Each segment differs from each other in hydrothermal activity,fault characteristics,volcanic rocks and expanding periods.Therefore,recognizing the tectonic activity of each segment of the Okinawa Trough is important to clarify its complex geological features.On the basis of Curie depth derived from magnetic anomaly inversion in previous work,this paper used thermal modeling to explore the deep and shallow tectonic activity of the Okinawa trough.The modeling results indicate that the deep tectonic activity intensity in the asthenosphere of the south segment is about six times that of the middle and north segments,while the shallow tectonic activityintensity is relatively weak.This conclusion is in accordance with lots of existing geological and geophysical data.Compared with the middle and northern Okinawa trough,the southern Okinawa trough(1)underwent a deeper rifting;(2)has a deeper magma source for forming seafloor volcanic rocks,a weaker extent of crystallization differentiation,and a stronger extent of assimilation and contamination with continental crust;(3)developed more large faults cutting through sedimentary basements and fewer small fractures in the interior of sediments;(4)produced weaker magmatic intrusions through sediments;(5)developed fewer hydrothermal activity areas in the seafloor;and(6)possesses stronger current seismicity and deeper hypocenters.Based on the comparative analysis of modeling results and real data,we inferred that(1)in the northern Okinawa trough,some hydrothermal activity areas have not been found so far,or have lost energy during the evolutionary process,or have been covered by the Quaternary strata,and(2)the southern Okinawa trough has a potential to develop more hydrothermal activity areas.
【Fund】: 国家重点基础研究发展计划(973)项目(2013CB429701)资助
【CateGory Index】: P736.1
Download(CAJ format) Download(PDF format)
CAJViewer7.0 supports all the CNKI file formats; AdobeReader only supports the PDF format.
©2006 Tsinghua Tongfang Knowledge Network Technology Co., Ltd.(Beijing)(TTKN) All rights reserved