塔里木盆地西南缘古老层系巨厚黑色泥岩的发现及勘探意义

doi:10.7623/syxb201712001

石油学报 ›› 2017, Vol. 38 ›› Issue (12): 1335-1342,1370.DOI: 10.7623/syxb201712001

• 地质勘探 • 下一篇

塔里木盆地西南缘古老层系巨厚黑色泥岩的发现及勘探意义

朱光有, 杜德道, 陈玮岩, 孙琦森, 李婷婷, 张志遥, 陈志勇

中国石油勘探开发研究院北京 100083

收稿日期:2017-11-12 出版日期:2017-12-25 发布日期:2018-01-05
通讯作者: 朱光有,男,1973年11月生,1998年获石油大学(华东)学士学位,2003年获中国石油大学(华东)博士学位,现为中国石油勘探开发研究院二级专家,主要从事深层油气地质与成藏研究。Email:zhuguangyou@petrochina.com.cn
作者简介:朱光有,男,1973年11月生,1998年获石油大学(华东)学士学位,2003年获中国石油大学(华东)博士学位,现为中国石油勘探开发研究院二级专家,主要从事深层油气地质与成藏研究。Email:zhuguangyou@petrochina.com.cn
基金资助:
国家重大科技专项"塔里木盆地奥陶系—前寒武系碳酸盐岩油气资源潜力及目标优选"（2016ZX05004-004）和中国石油天然气股份有限公司项目"塔里木盆地震旦系—寒武系油气地质综合研究及接替领域优选和风险目标评价"资助。

The discovery and exploration significance of the old thick black mudstones in the southwest margin of Tarim Basin

Zhu Guangyou, Du Dedao, Chen Weiyan, Sun Qisen, Li Tingting, Zhang Zhiyao, Chen Zhiyong

PetroChina Research Institute of Petroleum Exploration and Development, Beijing 100083, China

Received:2017-11-12 Online:2017-12-25 Published:2018-01-05

摘要/Abstract

摘要：

前寒武系是全球一个重要的含油气层系。塔里木盆地该层系埋深大，一直未取得勘探突破，是否发育优质烃源岩也不确定。塔里木盆地西南部及昆仑山前十余万平方公里范围内，已钻探30多口探井，虽然发现了和田河、巴什托普、玉北、罗斯2等海相油气田，但始终未钻遇寒武系或奥陶系烃源岩，其油气来源也存在争议。近期笔者在盆地西南部踏勘中，发现一套巨厚的黑色页岩和泥岩，出露较好。实测泥页岩厚度大于140 m （未见顶，花岗岩体侵位），有机碳含量（TOC）主要分布在0.6%~1.9%，83块样品平均TOC为1.0%。最高热解温度T_max主要分布在490~520℃，相当于R_o在1.9%~2.9%。泥岩层中黄铁矿十分富集。根据地层接触关系及同位素定年，该地层年龄可能大于517 Ma，准确定年目前正在进行，因此暂且命名为"西昆仑黑色岩系"。通过板块构造分析，这套厚层泥岩可能在塔里木盆地西南部广泛分布，其形成有可能受裂陷槽的控制。这套黑色泥岩很可能是塔西南地区重要的烃源岩，提出塔里木盆地前寒武系—寒武系具备油气成藏的地质条件，该发现必将推动塔里木盆地向深层—超深层以及古老层系开展油气勘探工作。

关键词: 西昆仑黑色岩系, 优质烃源岩, 古老层系, 深层, 塔里木盆地

Abstract:

Precambrian is an important petroliferous strata in the world wide,but no breakthrough has been achieved in exploring the Precambrian strata of Tarim Basin due to huge depth,and the existence of high-quality source rocks remains uncertain. At present,more than thirty exploratory wells have been deployed within the southwest Tarim Basin and the pediment region of Kunlun Mountains with a total area exceeding 100 000 km². Despite the discoveries of some marine hydrocarbon fields including Hetianhe,Bashituopu,Yubei and Luosi 2,the Cambrian or Ordovician source rocks are never encountered,and there is also a dispute on the hydrocarbon source. Recently,a set of black shales and mudstones with huge thickness has been found with favorable outcrops in the exploration of southwest Tarim Basin. The total thickness of mudstones is measured to be more than 140 m (the top is not seen and penetrated by granite),and the TOC (total organic carbon)mainly varies in a range of 0.6% -1.9%,and an average of 1.0% is obtained based on the results of 83 samples. T_max (maximum pyrolytic temperature)is mainly distributed within 490℃-520℃,equivalent to the R_o of 1.9%-2.9%. Pyrites are very rich in mudstone beds. According to the contact relationship of different members and isotopic chronology,the age of these strata may be determined greater than 517 Ma,primarily considered as Sinian or Nanhua system and temporarily named the "Western Kunlun black rock series". The plate tectonic analysis results show that this set of thick black mudstones is possibly distributed widely in the southwest Tarim Basin,may be controlled by rifting troughs. Thus,this set of black mudstones may be the significant source rocks in the southwest Tarim Basin,indicating the geological conditions for hydrocarbon accumulations in the Precambrian-Cambrian strata. This discovery will definitely promote the hydrocarbon explorations in the deep and ultra-deep strata of the Tarim Basin.

Key words: Western Kunlun black rock series, high-quality source rocks, old system, deep strata, Tarim Basin

中图分类号:

TE122.14

朱光有, 杜德道, 陈玮岩, 孙琦森, 李婷婷, 张志遥, 陈志勇. 塔里木盆地西南缘古老层系巨厚黑色泥岩的发现及勘探意义[J]. 石油学报, 2017, 38(12): 1335-1342,1370.

Zhu Guangyou, Du Dedao, Chen Weiyan, Sun Qisen, Li Tingting, Zhang Zhiyao, Chen Zhiyong. The discovery and exploration significance of the old thick black mudstones in the southwest margin of Tarim Basin[J]. Acta Petrolei Sinica, 2017, 38(12): 1335-1342,1370.

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塔里木盆地西南缘古老层系巨厚黑色泥岩的发现及勘探意义

The discovery and exploration significance of the old thick black mudstones in the southwest margin of Tarim Basin

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