Full-Text Search:
Home|Journal Papers|About CNKI|User Service|FAQ|Contact Us|中文
《Journal of Chengdu University of Technology(Science & Technology Edition)》 2018-03
Add to Favorite Get Latest Update

REE characteristics of dolomites and indication of dolomitization fluid in Guanwushan Formation,NW Sichuan Basin,China

DENG Yuwei;HOU Mingcai;CHEN Anqing;MA Hualing;DONG Yixin;LUO Wen;HUANG Shuguang;State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation,Chengdu University of Technology;Northwest Sichuan Gas Field,Southwest Oil and Gas Field Branch,PCL;  
Based on the study of petrology characteristics of dolomite from three outcrops,the fluid characteristics in the formation process of dolomite in Devonian Guanwushan Formation,northwest Sichuan Basin are analyzed and its formation mechanism is investigated.Dolomite in this area can be divided into three types in terms of grain size:silty-fine grained dolomite,fine grained dolomite and medium grained dolomite.The analysis of REE shows that all the three types have low REE content expect few samples,with average of 25 ppm for silty-fine grained dolomite,18.4 ppm for fine grained dolomite and 18 ppm for medium grained dolomite.It also indicates that the dolomite possesses relatively high Y/Ho ratios(40)and most of samples lie in the ranges of 43.5~86.9,characteristic of ocean environment.The dolomite is enriched in LREE and depleted in HREE,with negativeanomalies of Eu(average 0.94),slight negative anomalies of Ce(average 0.81),positive anomalies of Y(average 2.98)and positive anomalies of La.The poor correlation of REE+Y content with Fe and Mn contents suggests a limited effect of terrigenous clastics on the dolomite.Different types of dolomite have similar REE patterns and similar to the REE patterns of limestone.The study indicates that the dolomite is formed by fluids of marine origin in a relatively close and reducing digenetic system.
【Fund】: 国家科技重大专项(2017ZX05008-005-009)
【CateGory Index】: P588.245
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