CAJ | 학술논문

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,~(87)Sr/~(86)Sr 值较低(小于0.709 67),δ~(13)C值为(0±1)‰的古海水环境中.
미량정(MT)탄산염암시발육재중、신원고대적특수탄산염암,전구분포엄범,MT구조유순정、등립적미량정방해석조성.천진계현중원고계고우장조발육봉부적MT탄산염암,병차재탁적암중발현신적MT류형.상측고우장조부면,통과미급선회류형화분、침적배경、비희이도해、소묘전경、전자탐침연구,병결합해평면변화、Sr화C동위소연구표명:원생MT구조주요발육재탄산염암태지조하형,심수비대칭형미급선회중상부적니정회암、세분설회암、개질니암이급탁적암구체적핵심부위;MT탄산염암주요발육재미급선회해평면상승적고수위시기,~(87)Sr/~(86)Sr 치교저(소우0.709 67),δ~(13)C치위(0±1)‰적고해수배경중.
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, mid-upper 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 ~(87)Sr/~(86)Sr value( <0.709 67) and δ~(13)C value((0±1)‰).