河北平泉中元古界高于庄组生境型及古环境  

Habitat types and palaeoenvironments of the Mesoproterozoic Gaoyuzhuang Formation in Pingquan,Hebei Province

作　　者：郭华[1,2] 杜远生[1,2] 黄俊华[1,2] 杨江海[2] 黄虎[2] 陈玉[2] 周瑶[2] 

机构地区：[1]中国地质大学(武汉)生物地质与环境地质教育部重点实验室,湖北武汉430074 [2]中国地质大学(武汉)地球科学学院,湖北武汉430074

出　　处：《古地理学报》2010年第3期269-280,共12页Journal of Palaeogeography：Chinese Edition

基　　金：中国石油化工股份有限公司海相油气勘探前瞻性项目(编号:G0800-06-ZS-319);国家自然科学基金项目(编号:40621002);"高等学校学科创新引智计划"项目(编号:B08030)联合资助

摘　　要：河北平泉中元古界高于庄组海相碳酸盐岩地层中发育大量不同形态类型的微生物岩,主要包括柱状叠层石、层纹状叠层石、核形石、纹理石以及凝块石,它们各自不同的宏体和微观构造特征代表了不同的水体深度和环境水动力条件。通过野外实测观察、室内偏光显微镜下254块岩石薄片的微相分析以及碳、氧同位素的分析测定,研究了整个高于庄组沉积时期菌藻类生物的演化过程。在综合考虑岩性岩相特征、生物碎屑的含量、颗粒的保存状态以及微生物岩的宏体和微观特征等因素的基础上,将整个高于庄组划分为18个生境型,沉积相带演化从潮上带至内陆架的上部。河北平泉中元古界高于庄组地层序列中菌藻类生物含量的变化以及碳同位素的迁移规律清楚地记录了高于庄组沉积时期大规模的海进—海退的旋回沉积过程以及短期内频繁的海平面升降变化。通过分析生境型在地层剖面的分布特征以及生物与环境之间的相互作用关系,为今后研究生物与环境之间的协同演化以及更有效地进行烃源岩的评价提供了良好的基础资料。Various types of morphological microbialites were developed in the marine carbonate rocks of the Mesoproterozoic Gaoyuzhuang Formation in Pingquan of Hebei Province. They mainly include five different types, namely, columnar stromatolites,laminated stromatolites, oncolites, biolaminates and thrombolites, which are characterized by their own special macro-and micro-structures, and thus can be taken as an indicator of varied water-depth and depositional environments. In this paper, we have conducted the field measurement of the Gaoyuzhuang Formation, analyzed 254 thin sections and C-O isotopes and made researches on the evolution processes of microbe and algae during the depositional period of the Gaoyuzhuang Formation. On the basis of lithologic facies features, the bioclastic magnitude, the grain preservation situation and the macro-and micro-characters of various microbialites, the whole Gaoyuzhuang Formation was divided into 18 habitat types, mainly occurring from supertidal to the upper shelf settings. The changes in bioclastic magnitude and C-isotope in the Gaoyuzhuang Formation illustrate clearly a transgression-regression cycle. Analyses of distribution feature of habitat types in the depositional sequence and the interaction between organism and environment have provided basic materials for further study of the coordinated evolution of organism and environment, and better evaluation of hydrocarbon source rocks.

关 键 词：微生物岩 生境型 碳同位素 古环境 高于庄组 河北平泉 

分 类 号：P588[天文地球—岩石学]