Detrital Zircon Geochronology and Provenance of Core Sediments in Zhoulao Town,Jianghan Plain,China  

作　　者：王节涛 李长安 杨勇 邵磊 

机构地区：[1]Faculty of Earth Sciences,China University of Geosciences [2]Key Laboratory of Biogeology and Environmental Geology of Ministry of Education,China University of Geosciences

出　　处：《Journal of Earth Science》2010年第3期257-271,共15页地球科学学刊（英文版）

基　　金：supported by the National Natural Science Foundation of China (Nos. 40771213,40672206);the National Basic Research Program of China (No.2004CB720204)

摘　　要：In our study,the U-Pb age spectrum of detrital zircons from terrigenous sediments is used to determine the sources.The Middle and Upper Reaches of the Yangtze River drain the western Yangtze craton and eastern Tibetan plateau,and take lots of sediments to the Jianghan （江汉） plain.Detrital zircons collected from Zhoulao （周老） core provide an ideal sample for the provenance studies.Here we report LA-ICP-MS U-Pb ages of 125 detrital zircons from one sand sample in the core sediments,which is recovered from a depth of 86.76-88.58 m and the paleomagnetic age is about 800 kaBP,in Zhoulao Town.The 125 zircons reveal nine major age peaks of 3.0,2.5-2.3,2.0-1.7 Ga,838-723,453-415,257,212,166 and 17 Ma.Only two zircons have ages of 14.8 and 16.5 Ma,their appearance indicates that the headwater of the Yangtze River had reached the Tibetan plateau about 800 ka ago.Our results also show that the Hanjiang （汉江） River did not influence the sediments of the Zhoulao core obviously at that time.In our study,the U-Pb age spectrum of detrital zircons from terrigenous sediments is used to determine the sources.The Middle and Upper Reaches of the Yangtze River drain the western Yangtze craton and eastern Tibetan plateau,and take lots of sediments to the Jianghan （江汉） plain.Detrital zircons collected from Zhoulao （周老） core provide an ideal sample for the provenance studies.Here we report LA-ICP-MS U-Pb ages of 125 detrital zircons from one sand sample in the core sediments,which is recovered from a depth of 86.76-88.58 m and the paleomagnetic age is about 800 kaBP,in Zhoulao Town.The 125 zircons reveal nine major age peaks of 3.0,2.5-2.3,2.0-1.7 Ga,838-723,453-415,257,212,166 and 17 Ma.Only two zircons have ages of 14.8 and 16.5 Ma,their appearance indicates that the headwater of the Yangtze River had reached the Tibetan plateau about 800 ka ago.Our results also show that the Hanjiang （汉江） River did not influence the sediments of the Zhoulao core obviously at that time.

关 键 词：detrital zircon U-Pb age PROVENANCE Zhoulao core Jianghan plain 

分 类 号：P597.3[天文地球—地球化学]