凤台砾岩与四顶山组过渡接触关系的发现及其地质意义
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摘要
凤台砾岩的特征是砾石磨圆差、无分选，主要来自下伏四顶山组叠层石灰岩、砂屑灰岩，砾石和胶结物均以碳酸盐岩为主．在寿县李冲乡的两个剖面上，凤台砾岩与下伏四顶山组叠层石灰岩具有指状交叉的过渡接触关系，具缓坡相特征的叠层石完好地生长于砾岩之上．研究表明，凤台砾岩是在四顶山组沉积的同时，由于地震（或其他地质作用）使得四顶山组灰岩破碎形成高密度流堆积于碳酸盐台地的缓坡环境而成．
The gravel stone of Fengtai Formation is characterized by lower psephicity, no sorting, and the predominance of carbonates in stramatolith limestone, sandyclastic limestone, gravels and cements coming from the underlying Sidingshan Formation. It is found in the two sections in Lichong, Shouxian County, that the gravel stone of Fengtai Formation has a transitional contact relation with the stromatolith limestone of Sidingshan Formation. The gravel stone and the stromatolith limestone form a finger-liked cross section. Some stromatolith grows right on the gravel stone. It is concluded that the gravel stone could have been accumulated in slope of the carbonate formed by high density flow, which is mainly composed of stromatolith limestone of Sidingshan Formation broken by simultaneous earthquakes.
The gravel stone of Fengtai Formation is characterized by lower psephicity, no sorting, and the predominance of carbonates in stramatolith limestone, sandyclastic limestone, gravels and cements coming from the underlying Sidingshan Formation. It is found in the two sections in Lichong, Shouxian County, that the gravel stone of Fengtai Formation has a transitional contact relation with the stromatolith limestone of Sidingshan Formation. The gravel stone and the stromatolith limestone form a finger-liked cross section. Some stromatolith grows right on the gravel stone. It is concluded that the gravel stone could have been accumulated in slope of the carbonate formed by high density flow, which is mainly composed of stromatolith limestone of Sidingshan Formation broken by simultaneous earthquakes.
引文
1徐嘉炜．华北南部寒武系下限问题．地质论评，1958，18（1）：41～562杨清和，张友礼，郑文武等．苏皖北部震旦亚界的划分和对比．见：中国震旦亚界．天津：天津科学技术出版社，1982．231～2653斗守初，汪贵翔，任润生等．安徽凤台、霍邱地区震旦纪冰成岩的再研究．见：胡维兴，沈其韩，陈晋镳主编．前寒武纪地质，第1号，中国晚前寒武纪冰成岩论文集．北京：地质出版社，1985．119～1444王翔，王战．皖西凤台组重力流及滑塌沉积．中国区域地质，1993，（2）：131～1395乔秀夫，季强，高林志等．北中国板块东部震旦系对比．中国区域地质，1996，（3）：135～1426高劢．碳酸盐岩Pb－Pb同位素测年及其地层研究中的应用：［学位论文］．北京：中国地质大学（北京），1995
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