摘要
文中列举了海相生物实体化石、海相痕迹化石、海相生物碎屑、以及海相自生矿物等实据后 ,认为在辽河至长江间的“第二沉降带”这一南北向区间 ,在孔店组—沙河街组沉积期 ,存在一条类似于北美的白垩纪海路(Cretaceousseaway)那样的海水通道 ,通道内海水水体浅 ,且停留时间短 ,只在高位期出现。此时海域 ,宽 1 2 0— 340km ,可从下辽河延伸到江汉盆地。就储层沉积环境而言 ,此时古构造台地区 ,可形成点礁或碳酸盐岩滩坝。到低位期 ,海水即离开“第二沉降带” ,转而成为星罗棋布的湖泊和下切河流 ,并随之出现与湖泊相关特别是与下切谷相关的储层。
Evidences of marine body fossils,trace fossils and shell debris as well as marine autogenic minerals show that a Tertiary seaway might have been existed in an area what called “the Second Depression zone”by J.S. Lee between Liaohe River and Yangtze River during the sedimentary period of Kondian Formation and Shahejie Formation. The Tertiary seaway is thought to be existed only in hight stand period. The water depth of the seaway was shallow probably not very much more than fair weather wave base. The original seaway could reach 120 340 km. wide and extended from Liaohe basin in the north to Jianghan basin in the south.The Patch reef and carbonate beach or barrier which could be treated as potential reservoir have developed somewhere in higher structural areas during high stand. In contrast to high stand period, the marine water retreated from “the Second Depression” during low stand period and the original seaway became lakes in lower structural area and incised rivers scattered in palaeovalley districts followed by incised drainage. The importance of fresh and brackish water valley filled deposits are strongly emphasized in this paper in terms of new reservoir prospecting.
出处
《古生物学报》
CAS
CSCD
北大核心
2004年第1期147-154,共8页
Acta Palaeontologica Sinica
基金
郑州大学科学研究基金资助项目
