天津蓟县高于庄组微亮晶(MT)碳酸盐岩的沉积环境及成因探讨  

Discussion on the Sedimentary Environment and Origin of the Microsparite Carbonates of Mesoproterozoic Gaoyuzhuang Formation in Jixian Area,Tianjin,China

作　　者：王德海[1] 孟祥化[2] 郭峰[2] 任国选[2] 葛铭[2] 

机构地区：[1]吉林大学地球科学学院,长春130061 [2]中国地质大学沉积盆地研究所,北京100083

出　　处：《吉林大学学报（地球科学版）》2009年第6期1023-1030,共8页Journal of Jilin University：Earth Science Edition

基　　金：国家自然科学基金项目(40572073;40172043);中国地质调查局地质调查项目(200313000055);国际地质对比计划项目IGCP447(SC/GEO/546/447)

摘　　要：微亮晶(MT)碳酸盐岩是发育在中、新元古代的特殊碳酸盐岩,全球分布广泛,MT构造由纯净、等粒的微亮晶方解石组成。天津蓟县中元古界高于庄组发育丰富的MT碳酸盐岩,并且在浊积岩中发现新的MT类型。详测高于庄组剖面,通过米级旋回类型划分、沉积环境、费希尔图解、扫描电镜、电子探针研究,并结合海平面变化、Sr和C同位素研究表明:原生MT构造主要发育在碳酸盐岩台地潮下型,深水非对称型米级旋回中上部的泥晶灰岩、细粉屑灰岩、钙质泥岩以及浊积岩球体的核心部位;MT碳酸盐岩主要发育在米级旋回海平面上升的高水位时期,87Sr/86Sr值较低(小于0.70967),δ13C值为(0±1)‰的古海水环境中。Abundant microsparite（MT） carbonates was found in the Mesoproterozoic Gaoyuzhuang Formation in Jixian area, Tianjin City. A new type of MT was also found in turbidites. Meter-scale cycle and sedimentary environment were analyzed by using technologies of profile detailed measured, fischer plot, scanning electron microscope, electron probe and isotopes of Sr and C. Primary MT structures of Gaoyuzhuang Formation were mainly developed in the subtidal of carbonate mesa, midupper meter-scale cycle of deep-water asymmetric type（micrite and calcareous mudstone ） and core of the turbidites. The MT carbonates were developed during HST stage of meter-scale cycle in paleo-ocean sedimentary environment with the low ^87Sr/^86Sr value（ 〈0. 709 67） and δ^13C value（（0±1）‰）.

关 键 词：高于庄组 中元古代 微亮晶碳酸盐岩 蓟县 矿物学 

分 类 号：P618.13[天文地球—矿床学]