Welcome to Petroleum Geology Forums

This is a free online community that aims to bring petroleum professionals and geologists together and share valuable knowledge. Registration is easy so become a member now for instant free access.
  • Petroleum Geologists can stay up to date with industry related topics and exchange ideas and concepts.
  • Upstream Oil and Gas Consultants get a chance to share their expertise and gain exposure to land future projects.
  • Geology students and graduates can join the discussion and get into contact with potential future employees.

  >> Register Now





Post new topic Reply to topic  [ 1 post ] 
Rapid exhumation of basement rocks along the northern... 
Author Message

Joined: Fri Mar 11, 2011 9:00 pm
Posts: 238
Post Rapid exhumation of basement rocks along the northern...
Basin Research: Rapid exhumation of basement rocks along the northern margin of the North China craton in the early Jurassic: evidence from the Xiabancheng Basin, Yanshan Tectonic Belt

Early Mesozoic Basins in the Yanshan Fold–Thrust Belt (YFTB), located along the northern margin of the North China Craton (NCC), record significant intraplate deformation of unknown age. In this article, we present evidence for the rapid exhumation of high‐grade basement rocks along the northern margin of the NCC in the Early Mesozoic. U–Pb geochronology of detrital zircons constrains the maximum depositional ages of syntectonic sedimentary units that formed during the unroofing of basement rocks and plutons in the Xiabancheng Basin. In the Early Mesozoic, the Xiabancheng Basin recorded a dramatic transformation in depositional environments, related to a significant change in the regional tectonic setting. In this study, the tectonic evolution of the YFTB is established from paleocurrent data and U–Pb zircon ages of sandstone and granitic gravels of the Xingshikou Formation, Xiabancheng Basin. The paleocurrent direction of meandering fluvial facies in the Triassic Liujiagou and Ermaying Formations are from east to west. In contrast, the overlying Xingshikou Formation consists of alluvial fan facies with paleocurrent directions from north‐northwest to south‐southeast. The lower and middle segments of the Xingshikou Formation record rapid exhumation of basement rocks along the northern margin of the NCC. U‐Pb ages of detrital zircons within the Xingshikou Formation are characterized by three major U–Pb age groups: 2.2–2.5 Ga, 1.7–1.8 Ga and 193–356 Ma. From 193 Ma to 356 Ma, a subsidiary peak occurs at 198 ± 5 Ma, constraining the sedimentation age of the Xingshikou Formation to the Early Jurassic. Zircon from the Wangtufang pluton in the northern portion of the Xiabancheng Basin yields U–Pb ages of 191 ± 1 Ma and 207 ± 1 Ma. Within error, these crystallization ages are identical to detrital zircon ages of 206 ± 1 Ma and 206 ± 2 Ma obtained for granitic gravel clasts in the Xingshikou Formation. Thus, the Wangtufang pluton and surrounding basement rocks must have experienced rapid uplift and exhumation during the Early Jurassic. The onset of exhumation along the northern margin of the NCC occurred at ca. 198–180 Ma.

Go to Article


Thu Jan 19, 2012 12:52 pm
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 1 post ] 


Related topics 
 Topics   Author   Replies   Views   Last post 
There are no new unread posts for this topic. Rapid extensive erosion of the North Alpine foreland...

ArticlePoster

0

532

Sat Mar 12, 2011 7:40 pm

ArticlePoster View the latest post

 



Search for:
Jump to:  
cron


Content on EPGeology.com is intended for personal use only and to supplement, not replace, professional judgment. EPGeology.com disclaims any and all liability for your use of its content. As most of our content is supplied by our users we can not check copyright, and stress that copyright remains at the original owner. If you suspect copyright infringement please use the contact form to report it.
Contact || © EPGeology.com. || Powered by phpBB Asteroid Mining

phpBB SEO