京津晋冀寒武系第三统鲕粒灰岩特征及其环境意义_赵鹏沄

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中国石油化工股份有限公司海相前瞻性项目(C0800-07-ZS-162)资助

收稿日期: 2010-10-13; 修回日期: 2010-12-14; 网络出版日期: 2011-08-19 网络出版地址: /kcms/detail/11.2442.N.20110819.1638.011.html

北京大学学报(自然科学版), 第47卷, 第5期, 2011年9月　

Acta Scientiarum Naturalium Universitatis Pekinensis, Vol. 47, No. 5 (Sept. 2011)　

京津晋冀寒武系第三统鲕粒灰岩特征及其环境意义

赵鹏沄1,2 刘波2,† 秦善1

1. 北京大学地球与空间科学学院, 北京 100871;

2. 北京大学石油与天然气研究中心, 北京 100871;

† 通信作者, E-mail: bobliu@

摘要 京津晋冀地区是华北板块的主体, 该区寒武系第三统以鲕粒灰岩的广泛发育为特点。通过野外露头剖面和室内薄片观察, 对研究区鲕粒灰岩空间展布和鲕粒类型进行了详细研究。鲕粒灰岩从东到西出现的层位逐渐抬高, 具有明显的穿时性。大型鲕滩呈向西凸出的弧形带状分布, 鲕滩带主体由同心鲕鲕粒灰岩组成, 鲕滩带西侧鲕粒灰岩厚度迅速减小, 鲕粒以放射鲕居多, 鲕滩带东侧鲕粒灰岩厚度逐渐减小, 鲕粒以同心鲕占绝对优势。寒武纪第三世海侵方向是由东向西, 在研究区中部发育内缓坡的鲕粒滩环境, 西部为滩后潮坪环境, 东部为开阔海环境。

关键词 华北; 寒武系第三统; 鲕粒灰岩; 环境意义 中图分类号 P581

The Third Series of Cambrian Oolitic Limestones and Their Sedimentary Environment in Beijing, Tianjin, Shanxi and Hebei Provinces, North China

ZHAO Pengyun 1,2, LIU Bo 2,†, QIN Shan 1

1. School of Earth and Space Sciences, Peking University, Beijing 100871;

2. Institute of Oil and Gas, Peking University,

Beijing 100871; † Corresponding author, E-mail: bobliu@

Abstract The study area, geographically including Beijing, Tianjin, Shanxi and Hebei Provinces, is the main part of the North China Plate. Based on the study of outcrop and thin section observation, the distribution pattern of oolitic limestone and its ooid characteristics are presented. Olitic limestones were widely distributed in the area during the Third Series of Cambrian. Generally, the oolitic limestone elevates in strata gradually from east to west, which indicates that the oolitic limestone is diachronous. Huge oolitic shoals distribute along a western ward bulging belt from north to south, and mainly are composed of concentric ooids. In west of the belt, the thickness of the oolitic limestone decreases rapidly, and the oolitic limestone mainly is composed of radial ooids. In east of the belt, the oolitic limestone thins gradually, with majority grains of concentric ooids. The marine transgression during the Third Epoch of Cambrian took place from east to west on the North China Plate. In this background, the inner ramp ooid shoals developed in the central belt of the study area, with open sea in the east and shoal back tidal flat in the west.

Key words North China; the Third Series of Cambrian; oolitic limestone; sedimentary environment

鲕粒自17世纪早期被发现以来[1], 一直是碳酸盐岩中最引人注目的颗粒类型, 其原因不仅在于鲕粒具有特殊的宏观形态、简单的组分特征和复杂的沉积组构, 更重要的在于其对环境极其敏感, 在研究沉积环境和成岩环境时, 它是一种十分灵敏的标

志[2]。正因为如此, 国内外学者通常将鲕粒作为碳

酸盐岩微相研究和沉积环境研究的重要标准[3−9]。

寒武系按照最新的划分方案划分为四统十阶, 即第一统、第二统、第三统和芙蓉统, 取代了国际地学界沿用了近170年的上、中、下三统的传统划

DOI ：10.13209/j.0479-8023.2011.115