四川盆地须家河组致密砂岩气自生伊利石年龄分布与成藏时代

doi:10.7623/syxb201511006

石油学报 ›› 2015, Vol. 36 ›› Issue (11): 1367-1379.DOI: 10.7623/syxb201511006

四川盆地须家河组致密砂岩气自生伊利石年龄分布与成藏时代

张有瑜^1,2,3, 陶士振¹, 刘可禹^1,2,3,4, 罗修泉¹

1. 中国石油勘探开发研究院北京 100083;
2. 中国石油天然气集团公司盆地构造与油气成藏重点实验室北京 100083;
3. 提高石油采收率国家重点实验室北京 100083;
4. CSIRO Earth Science and Resource Engineering Bentley Australia P.O. Box 1130

收稿日期:2015-05-03 修回日期:2015-09-01 出版日期:2015-11-25 发布日期:2015-12-05
通讯作者: 张有瑜,男,1955年8月生,1982年获中南大学学士学位,1988年获中国地质大学(北京)硕士学位,现为中国石油勘探开发研究院教授级高级工程师,主要从事油气储层自生伊利石K-Ar、Ar-Ar测年、He、Ar同位素质谱分析和含油气盆地黏土矿物研究。Email:ngms@petrochina.com.cn
作者简介:张有瑜,男,1955年8月生,1982年获中南大学学士学位,1988年获中国地质大学(北京)硕士学位,现为中国石油勘探开发研究院教授级高级工程师,主要从事油气储层自生伊利石K-Ar、Ar-Ar测年、He、Ar同位素质谱分析和含油气盆地黏土矿物研究。Email:ngms@petrochina.com.cn
基金资助:
中国石油天然气股份有限公司科技攻关项目"油气勘探新领域、新理论、新方法、新技术"(2011A-0207)资助。

Authigenic illite age and hydrocarbon accumulation time in Xujiahe Formation sandstone reservoirs (Upper Triassic), Sichuan Basin

Zhang Youyu^1,2,3, Tao Shizhen¹, Liu Keyu^1,2,3,4, Luo Xiuquan¹

1. PetroChina Research Institute of Petroleum Exploration and Development, Beijing 100083, China;
2. CNPC Key Laboratory of Basin Structure and Hydrocarbon Accumulation, Beijing 100083, China;
3. State Key Laboratory of Enhanced Oil Recovery, Beijing 100083, China;
4. Earth Science and Resource Engineering, Commonwealth Scientific and Industrial Research Organization, Bentley P. O. Box 1130, Australia

Received:2015-05-03 Revised:2015-09-01 Online:2015-11-25 Published:2015-12-05

摘要/Abstract

摘要：

利用自生伊利石K-Ar、Ar-Ar测年技术对四川盆地须家河组致密砂岩气藏的成藏年代进行测定与研究,并对其演化规律进行深入探讨。须家河组砂岩储层自生伊利石普遍发育,主要为片丝状、短丝状、丝状,具有明显的自生成因特征并且纵、横向分布稳定。须家河组砂岩储层自生伊利石年龄数据明显分为2组,具有2期成藏特征。早期成藏为晚侏罗世-早白垩世(97~145 Ma),广泛分布于川西、川中广大地区,是主要成藏期;晚期成藏为晚白垩世(78~83 Ma),仅见于川西南端平落坝、白马庙气田须家河组二段。主要成藏期也即早期成藏,主力储层须家河组二段、须家河组四段、须家河组六段基本一致,并明显具有连续成藏特征:纵向上,自下而上依次变晚,须家河组二段略早(平均133 Ma)、须家河组四段略晚(平均127 Ma),须家河组六段主要分布在广安气田,与须家河组四段相比也基本具有下早上晚的成藏特征(须家河组四段平均139 Ma,须家河组六段平均134 Ma);平面上,川西须家河组二段由北向南依次变晚,中坝、新场、大邑气田的自生伊利石平均年龄分别为136 Ma、134 Ma和133 Ma(川西南端的平落坝、白马庙气田属于晚期成藏),川中须家河组二段、须家河组四段由东向西依次变晚,东部的广安、合川、荷包场气田略早,中西部的磨溪、充西-莲池、金华、八角场气田略晚。自生伊利石年龄分布特征表明,烃源岩埋深,即生、排烃时间,是须家河组砂岩气藏成藏早晚的最主要控制因素,埋深大、生、排烃早,则年龄大、成藏早,反之则年龄小、成藏晚。岩性对成藏具有一定的控制作用,但分布局限。构造抬升作用主要表现在成藏后期的调整阶段,年龄由东向西变小,即成藏由东向西变晚,与现今埋深即东高西低的构造特征不一致现象,是由成藏后期的构造差异抬升作用所致。

关键词: 须家河组砂岩储层, 自生伊利石, K-Ar测年, 未真空封装Ar-Ar测年, 成藏年代

Abstract:

K-Ar and Ar-Ar dating technologies of authigenic illite are used to determine and study the hydrocarbon accumulation time of tight sandstone gas reservoirs in Xujiahe Formation, Sichuan Basin, and its evolutionary laws are deeply discussed. The authigenic illite of sandstone gas reservoirs in Xujiahe Formation is widely developed, mainly shaped in plate filamentous, short filamentous and filamentous forms, and characterized by significant authigenic origin as well as stable vertical and lateral distribution. The ages of authigenic illite in sandstone reservoirs of Xujiahe Formation were divided into two distinct groups indicating two-phase hydrocarbon accumulation characteristics. The early-phase accumulation occurred in Late Jurassic-Early Cretaceous (97-145 Ma), widespread in the western and central Sichuan Basin, i.e., the main accumulation phase. The late-phase accumulation occurred in Late Cretaceous (78-83 Ma), and only in Member 2 of Xujiahe Formation, Pingluoba and Baimamiao gas fields in the southwestern Sichuan Basin. In terms of major reservoirs in the main accumulation phases, i.e., the early accumulation phases, Member 2, Member 4 and Member 6 of Xujiahe Formation are basically consistent with significant continuous accumulation characteristics. Vertically, the accumulation is progressively later from lower to upper reservoirs, i. e., Member 2 of Xujiahe Formation presents earlier accumulation (133 Ma on average), while Member 4 of Xujiahe Formation shows later accumulation (127 Ma on average). Member 6 of Xujiahe Formation is mainly developed in Guang'an gas field with basic accumulation characteristics of earlier in the lower while later in the upper, as compared with Member 4 of Xujiahe Formation (139 Ma and 134 Ma on average in Member 4 and Member 6). Horizontally, the accumulation of Member 2 of Xujianghe Formation in western Sichuan Basin is progressively later from north to south. The average ages of authigenic illite in the Zhongba, Xinchang and Dayi gas fields are 136 Ma, 134 Ma and 133 Ma respectively (Pingluoba and Baimamiao gas fields in the southwestern Sichuan Basin show late-phase accumulation). The accumulation of Member 2 and Member 4 of Xujiahe Formation in the central Sichuan Basin is progressively later from east to west. Guang'an, Hechuan and Hebaochang gas fields in the east present slightly earlier accumulation, while Moxi, Chongxi-Lianchi, Jinhua and Bajiaochang gas fields in the central-western area show later accumulation. The age distribution characteristics of authigenic illite indicate that the burial depth of source rocks, i.e., hydrocarbon generation and expulsion time, is the main controlling factor for accumulation age of sandstone gas reservoirs in Xujiahe Formation. The greater the buried depth is and the earlier the hydrocarbon generation and expulsion is, the older the ages would be and the earlier the accumulation would be, otherwise the younger the ages would be and the later the accumulation would be. Lithology had a certain control effect on hydrocarbon accumulation, but with limited distribution. The tectonic uplifting was mainly exerted in the adjustment stage during the late phase of accumulation. The age is younger from east to west, i.e., the accumulation occurred later from east to west, inconsistent with the current buried depth, i.e., the tectonic characteristics of higher in the east while lower in the west, which was caused by tectonic differential uplift in the late phase of accumulation.

Key words: sandstone reservoirs in Xujiahe Formation, authigenic illite, K-Ar dating, non-encapsulated Ar-Ar dating, accumulation age

中图分类号:

TE122

张有瑜, 陶士振, 刘可禹, 罗修泉. 四川盆地须家河组致密砂岩气自生伊利石年龄分布与成藏时代[J]. 石油学报, 2015, 36(11): 1367-1379.

Zhang Youyu, Tao Shizhen, Liu Keyu, Luo Xiuquan. Authigenic illite age and hydrocarbon accumulation time in Xujiahe Formation sandstone reservoirs (Upper Triassic), Sichuan Basin[J]. Acta Petrolei Sinica, 2015, 36(11): 1367-1379.

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四川盆地须家河组致密砂岩气自生伊利石年龄分布与成藏时代

Authigenic illite age and hydrocarbon accumulation time in Xujiahe Formation sandstone reservoirs (Upper Triassic), Sichuan Basin

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