摘要
提出松辽盆地营城组自下而上应划分为 3段 ,即中基性火山岩及含煤碎屑岩段、酸性火山岩段、含煤碎屑岩及中基性火山岩段。其中酸性火山岩段中的流纹岩是区域地层划分对比的标志岩性。首次在松辽盆地三站地区深层中发现孢粉化石 ,其孢粉组合特征可与松辽盆地东南缘九台地区、北部北安地区营城组孢粉组合对比。孢粉组合中出现了Appendisisporitessp 、Aequitriraditessp 、Pilo sisporitessp 、Klukisporitessp 等早白垩世特有或在早白垩世繁盛的分子 ,特别是Cicatricosisporitesaustraliensis (Balme)Potonie的含量高达 31 8% ,以及没有出现原始被子类花粉这一特征 ,可将三站地区营城组时代进一步确定为早白垩世中期 (大致相当巴列姆期 )。据孢粉化石所属母体植物的生态特征 ,推测该区营城组沉积时属温暖湿润的亚热带气候 。
The Yingcheng Formation in Songliao Basin might be divided into three members from bottom to top,namely meso basaltic volcanics coal bearing clastic rock member, acidic volcanics member(AVM) and coal bearing clastic rocks meso basaltic volcanics member.Among them,the rhyolite of AVM is an indication of regional correlation of Lower Cretaceous. Spore and pollen fossils were found for the first time in the Sanzhan area of Songliao Basin.The character of this fossils assemblage is similar to those contemporary assemblages in Jiutai area,which located in the southeast margin of Songliao Basin and Beian area in the north part of Songliao Basin.Some special genera which limited to or prosperd in early Cretaceous are found in the present assemblage: naming as Appenisisporites,Aequitriadites,Pilosisporites,Klukisporites,etc. Especially,Cicatricosisporites Australiensis(Balme) Potonie amounts to 31.8% of total spores and pollens.Furthermore, there aren't any angiosperm pollens. Thus the age of Yingcheng Formation might be of middle stage in Early Cretaceous(Barremian).According to the ecological characters of spore and pollen vegetation,the climate might be warm and humid,belonging to the sub tropical enviromment during the deposition of Yingcheng Formation in the present area; but aridity climate from the south disturbs irregularly.
出处
《大庆石油地质与开发》
CAS
CSCD
2002年第2期12-14,共3页
Petroleum Geology & Oilfield Development in Daqing
