摘要
车排子油田钻遇地层时代依据不足,地层划分与对比认识多有分歧。如前人在车探1井等井中所划分的莫老坝组无年代学依据。车探1井中同时出现莫老坝组和包古图组2个分属不同小区的地层,使车排子油田与盆北缘包古图小区地层系统对比混乱。笔者于车探1井3538~3774 m井段原划莫老坝组的岩心取孢粉样品分析,样品中裸子植物花粉含量为53.50%,蕨类植物孢子含量为46.50%,主要孢粉组合为Cyathidites minor-Osmundacidites-Deltoidospora-Pinuspollenites-Disacciatrileti-Cycadopites,时代为中侏罗世。结合岩石组合、孢粉时代及区域对比,将原定“上石炭统莫老坝组”重新厘定为中侏罗统西山窑组。取消“莫老坝组”一名后,车排子油田全部地层序列与包古图地层小区具有可比性。
In Chepaizi oilfield, the stratigraphic age is insufficient, while the views of stratigraphic division and correlation have divergence, for example, the Molaoba formation in well Chetan 1, divided by predecessors, has no Stratigraphic-Time basis. Molaoba formation and Baogutu formation, which belong to different areas, occur simultaneously in well Chetan 1, resulting in the stratigraphic system correlation between the whole oilfield and Baogutu area become very confusion. Sporopollen samples were taken from the cores of the 3 538~3 774 m well section of well Chetan 1 that divided as Molaoba formation for analysis. The results show that content of gymnosperm pollen and fern spore in the samples is 53.50% and 46.50%, respectively The main sporopollen assemblage is Cyathidites minor-Osmundacidites-Deltoidospora-Pinuspollenites-Disacciatrileti-Cycadopites, suggesting that the age of the formation is Middle Jurassic. Combined with rock assemblage, sporopollen age and regional correlation, the original “Molaoba formation of Late Carboniferous” should be redefined as Xishanyao formation of Middle Jurassic. After canceling the name of “Molaoba formation”, all stratigraphic sequences of Chepaizi oilfield are similar to Baogutu stratigraphic area.
作者
张誉洋
李永军
郑孟林
段丰浩
徐倩
郭文建
余海涛
任海姣
王韬
ZHANG Yuyang;LI Yongjun;ZHENG Menglin;DUAN Fenghao;XU Qian;GUO Wenjian;YU Haitao;REN Haijiao;WANG Tao(School of Earth Science and Resources,Chang’an University,Xi'an 710054,Shaanxi,China;Research Institute of Exploration and Development,Xinjiang Oilfield Company,PetroChina,Karamay 834000,Xinjiang,China)
出处
《西北地质》
CAS
CSCD
北大核心
2022年第2期157-165,共9页
Northwestern Geology
基金
新疆油田公司2020—2021年油气勘探科技外协项目“西部隆起石炭系建造与演化及其在盆地内部的响应与对比”(20201021)。
关键词
车排子油田
车探1井
孢粉化石
西山窑组
莫老坝组
Chepaizi oilfield
Well Chetan 1
sporopollen fossils
Xishanyao formation
Molaoba formation
