Full-Text Search:
Home|Journal Papers|About CNKI|User Service|FAQ|Contact Us|中文
《Acta Sedimentologica Sinica》 2018-03
Add to Favorite Get Latest Update

Diagenetic Facies and Its Geochemical Characteristics of Dolomite: A case study of Ma5_5-Ma5_1 Sub-Members of Majiagou Formation in central-eastern Ordos Basin

LI BaiQiang;WANG QiCong;ZHANG XiaoLi;WEI Wei;Department of Geology/National & Local Joint Engineering Research Center of Carbon Capture and Storage Technology,Northwest University;School of Earth Sciences and Engineering,Xi'an Shiyou University;  
It is important to study on the diagenetic facies of dolomite for the restoration of its diagenetic environment.The cores and thin sections as well as the whole rock major and trace element geochemistry,O,C and Sr isotopic compositions were analyzed to study the diagenetic facies types and lithofacies of the dolomite as well as the geochemistry of different diagenetic facies of Ma5_5-Ma5_1 sub-members of Majiagou Formation in the central-eastern Ordos Basin,respectively. The results show that the diagenetic facies of dolomite of Ma5_5-Ma5_1 sub-members in central-eastern Ordos Basin mainly include the gypsum and salt dissolution,active reflow seepage dolomitization and implicit reflux seepage dolomitization diagenetic facies in a near-surface diagenetic tract,and weathering karstific breccia diagenetic facies in an epidiagenetic tract. The former dolomite samples display lower δ~(18)O and δ~(13)C values than those of the Ordovician seawater,higher Mn and lower Fe contents,medium-strong cathodoluminescence,higher~(87)Sr/~(86)Sr ratios than the coeval seawater as well as their high Al and Ti contents may be caused by the effects of fresh water or mixed water,while the latter dolomite samples may be affected by the epigenetic coeval seawater shows relatively high Mn and significant high Fe contents,weak or non-cathodoluminescence,obvious higher~(87)Sr/~(86)Sr values than those of the coeval seawater,significant high Al and Ti contents. The results implicate that the δ~(18)O,δ~(13)C,~(87)Sr/~(86)Sr,major and trace elements are the effective indicators for identifying the diagenetic facies of dolomite.
【Fund】: 国家科技重大专项(2017ZX05005-002-004)~~
【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