APPLICATION OF MICROELEMENTS ANALYSIS IN IDENTIFYING SEDIMENTARY ENVIRONMENT——TAKING QIANJIANG FORMATION IN THE JIANGHAN BASIN AS AN EXAMPLE
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摘要: 湖泊沉积岩中的粘土矿物、泥岩和膏岩中的微量元素组成对沉积环境的水文变化很敏感,可以有效揭示湖平面的变化。封闭盐湖的沉积记录在垂向上以显著的岩性变化为特征,它们取决于河水补给与蒸发、沉淀和渗透之间的平衡作用,并导致湖平面的相应变化和湖岸线的频繁迁移。文中选取江汉盆地潜江组中对沉积环境反映最为敏感的硼(B)、锶(Sr)、钡(Ba)、钛(Ti)、铁(Fe)、磷(P)、锰(Mn)等微量元素指标,分析其在不同层序、不同体系域的变化特征,并讨论其环境意义。沉积岩中B含量一般比岩浆岩高,在页岩中其含量可达135×10-6,砂岩中较低,一般为(1~40)×10-6。Sr元素在咸水中含量一般为0.8‰~1‰,在淡水中的含量一般为0.1‰~0.3‰。Abstract: The compositions of microelements in clay minerals,mud rock and gypsum in lake sediments are very sensitive to the change of sedimentary environment.It may reveal lake-level change.The lithology change of sediment in saline lake in vertical is distinct,this change is controled by the balance in supply,evaporation and sediment of the river,which lead to the change of lake level.The paper mainly introduces using microelements,B,S,Ba,Ti,Fe,P,Mn etc.,in the Qianjiang Sag of the Jianghan Basin as an indication for sedimentary environment change to analyse the characteristics of change in different sequence and different systems tract,and discusses paleoclimate and sedimentary environment in different sequence.The content of B in sedimentary rock is more then in igneous rock commonly.The content of B is 135×10-6 in shale and(1~40)×10-6 in sand rock.The content of Sr is 0.8‰~1‰ in saline lake and 0.1‰~0.3‰ in freshwater.
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Key words:
- microelements /
- saline lake /
- paleoclimate /
- sedimentary environment /
- Qianjiang Formation /
- the Qianjiang Sag /
- the Jianghan Basin
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[1] Miller E K,Blum J D,Friedland A J.Determination of soil exchanheable-cation loss and weathering rates using Sr isotope[J].Nature,1993,362:438~441 [2] Bailey S W,Hornbeck J W,Priscoll C T,et al.Calcium inputs and transport in a base poor forest ecosystem as interpreted by Sr isotopes[J].Water Resource Res,1996,32:707~719 [3] Reinhardt E G,Blenkinsop J,Patrerson R T.Assessment of a Sr isotope(87Sr/86Sr)vital effect in marine taxa from Lee Stocking Islandt Bahamas[J].Geo-Marine Letters,1998,18(3):241~246 [4] 张义纲.油气地球化学的若干展望[J].石油实验地质,2005,27(5):484~489 [5] 孙镇城,杨藩,张枝焕等.中国新生代咸化湖泊沉积环境与油气生成[M].北京:石油工业出版社,1997 [6] 谭红兵,于升松.我国湖泊沉积环境演变研究中元素地球化学的应用现状及发展方向[J].盐湖研究,1999,(3):58~65 [7] Couch E L.Calculation of paleosalinities from boron and clay mineral data[J].AAPG Bull,1971,55(10):1829~1837 [8] 邓宏文,钱凯.沉积地球化学与环境分析[M].兰州:甘肃科学技术出版社,1993.34~35 [9] 刘群.中国中、新生代陆源碎屑:化学岩型盐类沉积[M].北京:科学技术出版社,1987.240~244 [10] 中国科学院贵阳地化所译.锶同位素地球化学[M].北京:科学出版社,1975.208 [11] 马宝林,王琪.青海湖现代沉积物的元素分布特征[J].沉积学报,1997,15(3):120~125 [12] 袁宝印,陈克造.青海湖的形成与演化趋势[J].第四纪研究,1990,(3):233~243 [13] 赵克斌,孙长青.油气化探在天然气勘探中的应用[J].石油实验地质,2004,26(6):574~579 [14] 张涛,云露.邬兴威等.锶同位素在塔河古岩溶期次划分中的应用[J].石油实验地质,2005,27(3):299~303 -
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