
第29卷
第3期
2015年6月
现代地质 GEOSCIENCE
Vol. 29
Na3 Jun.2015
内蒙古东部中二叠世吴家屯组海平面相对
变化的泥岩地球化学证据
明承栋,侯读杰2,赵省民3,宋健,邓坚3,吴赛赛3(1.中海油能源发展股份有限公司工程技术分公司,广东深圳518067;2.中国地质大学(北京)
能源学院,北京100083;3.中国地质调查局油气资源调查中心,北京100029;
4.中国石油大学(北京)地球科学学院,北京102249)
摘要:对内蒙古东部中二叠统吴家屯组泥岩进行了微量元索和有机地球化学研究,显示研究区吴家电组水体的古盐度范围为16.6%e~28.7%e,主要为半威水沉积。微量元素及其比值可以反映古盐度和古水深的变化,两者受海平面相对变化的影响;且古盐度、海平面相对升降在沉积相上有较好的响应。利用定量计算的古盐度和反映古盐度的St/Ba B/Ga值等编制了海平面相对变化曲线,显示研究区吴家屯组发生了2次海侵海退旋回,海侵发生在吴家屯组底部和中部。根据沉积相分析,结合地球化学指标V/(V+Ni)值、稀土元素Cem及饱和烃气相色谱,表明区内吴家电组主体
为缺氧、还原的浅海陆棚环境,该环境有利于有机质的保存和烃源岩的发育。关键词:吴家电组;泥岩;地球化学;古盐度;海平面变化;内蒙古东部
文章编号:10008527(2015)03062310
中图分类号:TE122.1
文献标志码:A
Sea-Level RelativeMovement of Middle Permian WujiatunFormation in
EasternInnerMongolia:EvidencefromMudstonesGeochemistry MING Cheng-dong', HOU Du-jie’, ZHAO Xing-min', SONG Jian', DENG Jian', WU Sai-sai?
(1. Ener Tech-Drlling & Production Co. CN00C, Shenzhen, Guangdong 518067, China; 2. School gf Energy Resources, China Unitersity of Geosciences, Bejing 100083, Chino:
3. Oil & Gas Sursey, China Geological Suney, Beijing 100029, Chin;
4. College of Geosciences, China Unitersily of Petroleum(Bejing) , Bejing 102249, Chine)
Abstract: Through studying the ICP- MS trace elements and organic geochemistry of the Middle Permian Wujia-tun Formation mudstones in eastem Inner Mongolia, it indicates that Wujiatun Formation mainly belongs to semi-salt water sedimentary environment; the range of palaeosalnity is 16. 6%e to 28. 7%e, The paleosalinity and the change of water depth are showed by the trace elements and their ratios, which are impacted by the relative change of sea- level. Palaeosalinity and relative change of sea-level have a good correlation with sedimentary fa-cies evolution. Using the quantitative calculation palaeosalinity and the values of Sr/ Ba and B/Ga which reflect the paleosalinity and the water depth, the curve of relative change of sea-level of Wujiatun Formation was estab-lished. The Wujiatun Formation had undergone two transgression-regression cycles and the transgressions took place in the bottom and middle part of Wujiatun Formation. According to the geochemical index of V/(V + Ni) values, rare earth element Ceamm and saturated hydrocarbon gas chromatogram, combined with sedimentary faci-
收稿日期:201406-23;改回日期:2015-0120;责任编辑:孙义梅。
基金项目:中国地质调查局项目"天山-兴象构造带石炭-二叠系对比研究"(1212011120966):国土资源部公益性行业科研专
项项目(201311022)。
作者简介:明承栋,男,硕士,1987年出生,矿产普查与勘探专业,从事沉积与油气地球化学研究。
Email;med495274550@163.com。
通信作者:侯读杰,男,博士,教授,1964年出生,石油地质学专业,从事油气地球化学及油气成爵研究。
Email: hdj@ cughb, edu, eno