酒泉盆地酒西坳陷主力烃源岩分布及对油气勘探的启示

doi:10.7623/syxb201811003

石油学报 ›› 2018, Vol. 39 ›› Issue (11): 1223-1240.DOI: 10.7623/syxb201811003

酒泉盆地酒西坳陷主力烃源岩分布及对油气勘探的启示

陈建平^1,2,3, 魏军⁴, 倪云燕^1,2,3, 陈建军⁴, 邓春萍^1,2,3, 田多文⁴, 胡健^1,2,3, 黄振凯^1,2,3, 张蒂嘉^1,2,3, 韩永科¹

1. 中国石油勘探开发研究院北京 100083;
2. 提高石油采收率国家重点实验室北京 100083;
3. 中国石油天然气集团公司油气地球化学重点实验室北京 100083;
4. 中国石油玉门油田公司甘肃酒泉 735000

收稿日期:2017-10-27 修回日期:2018-04-10 出版日期:2018-11-25 发布日期:2018-12-10
通讯作者: 陈建平,男,1962年10月生,1983年获山东矿业学院学士学位,2003年获中国矿业大学(北京)博士学位,现为中国石油勘探开发研究院教授级高级工程师,主要从事油气地球化学研究工作。Email:chenjp@petrochina.com.cn
作者简介:陈建平,男,1962年10月生,1983年获山东矿业学院学士学位,2003年获中国矿业大学(北京)博士学位,现为中国石油勘探开发研究院教授级高级工程师,主要从事油气地球化学研究工作。Email:chenjp@petrochina.com.cn
基金资助:
中国石油天然气股份有限公司科技重大专项（2013E-3301）资助。

Determination of main source rocks in the Jiuxi depression of Jiuquan Basin and its implications for oil and gas exploration

Chen Jianping^1,2,3, Wei Jun⁴, Ni Yunyan^1,2,3, Chen Jianjun⁴, Deng Chunping^1,2,3, Tian Duowen⁴, Hu Jian^1,2,3, Huang Zhenkai^1,2,3, Zhang Dijia^1,2,3, Han Yongke¹

1. PetroChina Research Institute of Petroleum Exploration and Development, Beijing 100083, China;
2. State Key Laboratory of Enhanced Oil Recovery, Beijing 100083, China;
3. CNPC Key Laboratory of Petroleum Geochemistry, Beijing 100083, China;
4. PetroChina Yumen Oilfield Company, Ganshu Jiuquan 735000, China

Received:2017-10-27 Revised:2018-04-10 Online:2018-11-25 Published:2018-12-10

摘要/Abstract

摘要：

酒泉盆地酒西坳陷属于勘探程度非常高的典型含油气坳陷，其中青西凹陷青南次凹是主要生烃凹陷。随着探井数量增多和勘探深度不断加深，揭露的下沟组下部和赤金堡组越来越多，为重新认识该凹陷主力烃源岩及其生烃潜力提供了十分有利的条件。通过对青南次凹30多口探井大量烃源岩样品系统的地球化学分析和研究发现：下白垩统不同层段烃源岩的有机质丰度由上至下逐渐增高，中沟组和下沟组上段为一般烃源岩，而下沟组中段、下段和赤金堡组烃源岩有机质丰度高，且以Ⅱ₁型有机质为主，属于好和很好的优质烃源岩。下白垩统烃源岩有机质丰度总体上呈现中部最高，南、北两端略低的趋势，优质烃源岩主要分布于凹陷中部-东北部地区，下沟组中段、下段和赤金堡组均为主力烃源岩，而凹陷南部只有下沟组下段和赤金堡组属于好烃源岩，也是南部主力烃源岩；青南次凹下白垩统下沟组中段处于大量生油阶段，下沟组下段处于生油高峰阶段，赤金堡组处于成熟生油窗后期-高成熟生成凝析油气阶段；下沟组中段、下段和赤金堡组烃源岩生成并排出了大量原油，是青西凹陷主力生烃源岩，青南凹陷北部和中部中-深层具有良好的油气勘探潜力。这一认识对酒西坳陷油气精细勘探部署具有重要的指导作用。酒西坳陷的实例对中国其他高勘探程度盆地的精细勘探与研究也具有一定的启示作用。

关键词: 酒泉盆地, 酒西坳陷, 下白垩统烃源岩, 有机质丰度, 有机质类型, 成熟度, 生烃与排烃潜力

Abstract:

The Jiuxi depression in the Jiuquan Basin is a typical well-explored petroliferous depression, in which the Qingnan sag is the main petroleum generation sag. With the increase of the number of exploration wells and the depth of exploration in recent 10 years, more and more source rocks in the lower part of the Xiagou Formation and the Chijinpu Formation have been exposed, which provides valuable information for re-understanding the main source rock and its hydrocarbon generation potential in this sag. A detailed geochemical study on a large number of source rocks from more than 30 wells in the Qingnan sag has been carried out and the results indicate that the abundance of organic matter in the Lower Cretaceous source rocks increases from top to bottom, in which the source rocks in the Zhonggou Formation and the Upper Member of the Xiagou Formation are only fair source rock, while the source rocks in the Middle and Lower members of the Xiagou Formation and the Chijinpu Formation are good or very good source rocks with high content of organic matter dominated by Type Ⅱ kerogen. The organic matter abundance of the source rocks is generally the highest in the central region and slightly lower in the south and north, and the high potential source rocks are mainly distributed in the central-northeastern parts where the Middle and Lower members of the Xiagou Formation and the Chijinpu Formation are all main source rocks, while only the Lower Member of the Xiagou Formation and the Chijinpu Formation are good and main source rocks in the southern part. The Middle and the Lower members of the Xiagou Formation are at the stages of thermally mature and peak oil respectively, and the Chijinpu Formation is at the stage of late oil window to highly mature condensate. These source rocks are the main source rocks in the Qingnan sag, and have generated and expelled a large amount of crude oil. There is still good oil exploration potential in the central and northern parts of the Qingnan sag. These understandings have an important guiding role for the fine exploration of oil and gas in the Jiuxi depression. The example of the Jiuxi depression has an important enlightenment to the fine exploration and research of other well-explorated basins in China.

Key words: Jiuquan Basin, Jiuxi depression, Lower Cretaceous source rock, organic matter abundance, organic matter type, maturity, potential of hydrocarbon generation and expulsion

中图分类号:

TE122.2

陈建平, 魏军, 倪云燕, 陈建军, 邓春萍, 田多文, 胡健, 黄振凯, 张蒂嘉, 韩永科. 酒泉盆地酒西坳陷主力烃源岩分布及对油气勘探的启示[J]. 石油学报, 2018, 39(11): 1223-1240.

Chen Jianping, Wei Jun, Ni Yunyan, Chen Jianjun, Deng Chunping, Tian Duowen, Hu Jian, Huang Zhenkai, Zhang Dijia, Han Yongke. Determination of main source rocks in the Jiuxi depression of Jiuquan Basin and its implications for oil and gas exploration[J]. Acta Petrolei Sinica, 2018, 39(11): 1223-1240.

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酒泉盆地酒西坳陷主力烃源岩分布及对油气勘探的启示

Determination of main source rocks in the Jiuxi depression of Jiuquan Basin and its implications for oil and gas exploration

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