合肥盆地金寨油浸砂岩的地球化学特征

GEOCHEMICAL CHARACTERISTICS OF JINZAI OIL-SOAKED SANDSTONE IN THE HEFEI BASIN

陈建平 冀国盛 钟建华 鲁国明 李勇

CHEN Jian-ping JI Guo-sheng ZHONG Jian-hua LU Guo-ming LI Yong

中国科学院, 长沙大地构造研究所, 湖南, 长沙, 410013 2. 中国石化, 胜利油田有限公司勘探项目管理部, 山东, 东营, 257001 3. 石油大学, 地球资源与信息学院, 山东, 东营, 257061

Changsha Institute of Geotectonics, Academia Sinica, Changsha, Hunan 410013, China 2. Department of Exploration Administration, Shengli Oilfield, SINOPEC, Dongying, Shandong 257001, China 3. College of Earth Resources and Information, China University of Petroleum, Dongying, Shandong 257061, China

该文对合肥盆地金寨油浸砂岩的宏观岩石学、有机岩石学和有机地球化学特征以及油源进行了研究。油浸砂岩发现于合肥盆地南部中侏罗统三尖铺组(J2s)地层中,为长石砂岩,油多沿细层(纹层)或层面浸染;有机质呈分散沥青或油滴状充填于孔、缝中;有机碳(C)、氯仿沥青"A"含量低,这与油气迁移以及后来遭受氧化、生物化学作用有关;有机质母质以水生生物、藻类为主,属腐泥型,为还原环境的湖泊沉积;有机质演化已达成熟阶段,油源可能来自三尖铺组的烃源岩。舒城凹陷为合肥盆地油气勘探的有利区带。

The macropetrology, organic petrology, organic geochemical characteristics and oil source of Jinzai oil-soaked sandstone in the Hefei Basin were studied in this paper. The oil-soaked sandstone, which was discovered in the Middle Jurassic Sanjianpu (J2s) strata of the South Hefei Basin, is an arkose. Oil disseminates along microlayers (laminae) or bedding planes, and organic matter infills pores and fissures taking the shapes of dispersed bitumen or oil drops. Low content of organic carbon (C) and chloroform extracted bitumen "A" is related to hydrocarbon migration as well as the oxidation and biochemism subjected afterwards. The organic mother material, which is dominated by hydrobios and algae, belongs to the sapropel type and is lake deposit under reduction environment. The evolution of organic material has got to the mature stage, and the oil source may comes from the hydrocarbon source rock of the Sanjianpu Formation. So the Shucheng Depression is the favorable zone for the hydrocarbon exploration of teh Hefei Basin.

中国科学院知识创新工程项目(KZCX-113).

https://doi.org/10.11781/sysydz200203279