琼东南盆地中生界潜山天然气成藏模式

doi:10.19657/j.geoscience.1000-8527.2022.050

摘要/Abstract

摘要：

琼东南盆地基底潜山勘探面临地质年代不清、储层非均质性强及成藏条件复杂等难题。通过开展区域大地构造演化、基底锆石测年、潜山储层描述及成藏动力分析,明确潜山储层发育区及有利成藏区。研究表明,在印支运动、燕山运动及喜山运动叠加控制下,松南低凸起、陵南低凸起大面积发育印支期的花岗岩潜山储层,平面上北西、北东及近东西向三组断裂、裂缝交错切割成网,纵向上形成的风化带-裂缝带总厚度超300 m的双层结构,明确裂缝储层发育的关键因素为脆性矿物和双向流体改造。基于早渐新世古地貌及烃源岩沉积模拟实验研究,提高了崖城组陆源海相烃源岩TOC分布预测精度,明确了中央坳陷优质烃源灶分布规律。综合分析潜山-古近系储层、构造脊展布和崖城组烃源灶的时空配置关系,建立了“松南低凸起源外高潜山天然气长距离侧向有限运聚模式”及“陵南低凸起源边低潜山近距离高效运聚模式”,提出源边低潜山的L26-B是下步勘探的有利目标。

关键词: 印支期, 基底潜山, 裂缝储层, 陆源海相烃源岩, 成藏模式

Abstract:

The exploration of basement buried hill in Qiongdongnan basin is facing many problems, such as unclear geological age, strong reservoir heterogeneity and complex accumulation forming conditions. Through regional tectonic evolution, basement zircon dating, buried hill reservoir description and accumulation forming dynamic analysis, the development area and favorable accumulation area of buried hill reservoir are identified. The study shows that under the superimposed control of Indosinian, Yanshanian and Himalayan orogenic movements, Indosinian granite buried hill reservoirs are widely developed in Songnan low uplift and Lingnan low uplift. In plane view, three groups of faults and fractures in NW, NE and near EW directions are cut into a network, forming a double-layer structure with a total thickness of more than 300 m in weathering fracture zone vertically. It is clear that brittle minerals and bidirectional fluid transformation are the key factors for the development of fractured reservoirs. Based on the Early Oligocene paleogeomorphology and source rock sedimentary study, the accuracy of TOC distribution prediction of terrigenous marine source rocks in Yacheng Formation is improved, and the distribution law of high-quality hydrocarbon source in central depression is clarified. By comprehensive analysis of the relationship between the distribution of Paleogene burial hill reservoir and space-time configuration with Yacheng Formation hydrocarbon source stove, two natural gas accumulation models are established, which are “long-distance lateral migration and high buried hill limited-accumulation outside the source” and “short-distance migration and low buried hill efficient-accumulation alongside the source”.So L26-B is the the potential prospect.

Key words: Indosinian, basement buried hill, fractured reservoir, terrigenous marine source rock, hydrocarbon accumulation model

中图分类号:

甘军, 季洪泉, 梁刚, 何小胡, 熊小峰, 李兴. 琼东南盆地中生界潜山天然气成藏模式[J]. 现代地质, 2022, 36(05): 1242-1253.

GAN Jun, JI Hongquan, LIANG Gang, HE Xiaohu, XIONG Xiaofeng, LI Xing. Gas Accumulation Model of Mesozoic Buried Hill in Qiongdongnan Basin[J]. Geoscience, 2022, 36(05): 1242-1253.

图/表 11

图1 琼东南盆地构造纲要图[4]

Fig.1 Structural outline of Qiongdongnan basin[4]

图2 琼东南盆地中生代构造演化模式

Fig.2 Mesozoic tectonic evolution model of Qiongdongnan basin

表1 琼东南盆地基底锆石测年数据[22-23]

Table 1 Zircon dating data of basement in Qiongdongnan Basin[22-23]

盆地	构造单元	井名	井段/m	地层时代	岩性	同位素年龄/Ma
琼东南盆地	松涛凸起	Y9	2 697~2 850	白垩纪	花岗岩	106.9±1.1
	松涛凸起	S34-A	2 736~2 753	白垩纪	花岗岩	98.4±1.7~100±1.6
	松南低凸起	Y8-1	2 948~3 088.62	三叠纪	花岗岩	239~250
		Y8-3	2 948~3 088.62	三叠纪	花岗岩	239~250
		Y1-1	3 768~3 826	三叠纪	花岗岩	241.7~261.7

图3 松南低凸起Y8区潜山裂缝发育应力模式与期次

Fig.3 Stress model and stages of buried hill fracture development in Y8 area of Songnan low uplift

图4 Y8-3井潜山储层薄片(蓝色充填为裂缝、孔隙)

Fig.4 Thin section of buried hill reservoir in well Y8-3

图5 琼东南盆地典型井基岩裂缝发育特征

Fig.5 Bedrock fracture development map of typical wells in deep and shallow water of Qiongdongnan Basin

图6 琼东南盆地崖城组三角洲、浅海沉积体系陆源有机质分布模式

Fig.6 Distribution pattern of terrigenous organic matter in delta, shallow marine facies system of Yacheng Formation, Qiongdongnan Basin

图7 中央坳陷崖城组烃源岩TOC分布预测图

Fig.7 TOC distribution prediction of Yacheng Formation source rocks in central depression

图8 松南、宝岛凹陷Y8区地震剖面图(剖面位置见图1)

Fig.8 Seismic profile of Y8 area in Songnan and Baodao sags

图9 松南低凸起Y8区高潜山成藏模式(剖面位置见图1)

Fig.9 Accumulation model of Y8 high buried hill in Songnan low uplift

图10 陵南低凸起L26区低潜山成藏模式(剖面位置见图1)

Fig.10 Accumulation model of L26 low buried hill in Lingnan low uplift

参考文献 35

[1]	XU Changgui, YU Haibo, WANG Jun, et al. Formation conditions and accumulation characteristics of Bozhong 19-6 large condensate gas field in offshore Bohai Bay Basin[J]. Petroleum Exploration and Development, 2019, 46(1): 27-40. DOI URL
[2]	田立新, 刘杰, 张向涛, 等. 珠江口盆地惠州26-6大中型泛潜山油气田勘探发现及成藏模式[J]. 中国海上油气, 2020, 32(4): 1-11.
[3]	孙晓猛, 张旭庆, 张功成, 等. 南海北部新生代盆地基底结构及构造属性[J]. 中国科学: 地球科学, 2014, 44(6): 1312-1323.
[4]	龚再升, 李思田, 谢泰俊, 等. 南海北部大陆边缘盆地分析与油气聚集[M]. 北京: 科学出版社, 1997: 27-41.
[5]	何家雄, 刘海龄, 姚永坚, 等. 南海北部边缘盆地油气地质及资源前景[M]. 北京: 石油工业出版社, 2008: 17-33.
[6]	ZHENG Xiangli, XIAN Huali. Formation of the 1300 km wide intracontinental orogen and postorogenic magmatic province in Mesozoic South China: A flat-slab subduction model[J]. Geology, 2007, 35(2): 179-182. DOI URL
[7]	CUONG T X, WARREN J K. BACH Ho Field, a fractured granitic basement reservoir, Cuu Long Basin, offshore SE Vietnam: A “buried-hill”play[J]. Journal of Petrological Geology, 2009, 32(2): 129-156.
[8]	孙桂华, 高红芳, 彭学超, 等. 越南南部湄公盆地地质构造与沉积特征[J]. 海洋地质与第四纪地质, 2010, 30(6): 25-33.
[9]	YE T, WEI A, SUN Z, et al. The reservoir characteristics and their significance for deliverability in metamorphic granite buried hill: a case study from the JZS oil field in the Liaodong Bay Basin,NE China[J]. Arabian Journal of Geosciences, 2019, 12(20): 1-9. DOI URL
[10]	LUO J I, MORAD S, LIANG Z G, et al. Controls on the quality of Archean metamorphic and Jurassic volcanic reservoir rocks from the Xinglongtai buried hill, western depression of Liaohe basin, China[J]. AAPG Bulletin, 2005, 89(10): 1319-1346. DOI URL
[11]	LU B L, WANG P J, ZHANG G C, et al. Basement structures of an epicontinental basin in the northern South China Sea and their significance in petroleum prospect[J]. Acta Petrolei Sinica, 2011, 32(4): 580-587. DOI
[12]	HUANG J H, TAN X F, CHENG C J, et al. Structural features of weathering crust of granitic basement rock and its petroleum geological significance: A Case study of basement weathering crust of Dongping area in Qaidam Basin[J]. Earth Science, 2016, 41(12): 2041-2060.
[13]	周杰, 杨希冰, 杨金海, 等. 琼东南盆地松南低凸起古近系构造-沉积演化特征与天然气成藏[J]. 地球科学, 2019, 44(8): 2704-2713.
[14]	张迎朝, 甘军, 徐新德, 等. 琼东南盆地深水东区Y8-1含气构造天然气来源及侧向运聚模式[J]. 地球科学, 2019, 44(8): 2609-2616.
[15]	施和生, 杨计海, 张迎朝, 等. 琼东南盆地地质认识创新与深水领域天然气勘探重大突破[J]. 中国石油勘探, 2019, 24(6): 691-697. DOI
[16]	LU B L, WANG P J, LIANG J S, et al. Structural properties of paleo-South China Sea and their relationship with the Tethys and the Paleo-Pacific tectonic domain[J]. Journal of Jilin University (Earth Science), 2014, 44(5): 1442-1449.
[17]	张功成, 谢晓军, 王万银, 等. 中国南海含油气盆地构造类型及勘探潜力[J]. 石油学报, 2013, 34(4): 611-627. DOI
[18]	张功成. 南海北部深水区构造演化及其特征[J]. 石油学报, 2010, 31(4): 528-533. DOI
[19]	BARCKHAUSEN U, ENGELS M, FRANKE D. Evolution of the South China Sea:revised ages for breakup and seafloor spreading[J]. Marine and Petroleum Geology, 2014, 58: 599-611. DOI URL
[20]	FRANKE D, SAVVE D, PUBELLIER M, et al. The final rifting evolution in the South China Sea[J]. Marine and Petroleum Geology, 2014, 58: 704-720. DOI URL
[21]	JIAN Xincai, KAI Junzhang. A new model for the Indochina and South China collision during the Late Permian to the Middle Triassic[J]. Tectonophysics, 2009, 67(1): 35-43. DOI URL
[22]	琼东南盆地Y8-3、Y1-1井锆石定年检测报告[R]. 武汉: 中国地质大学(武汉)地球科学学院实验中心, 2021.
[23]	琼东南盆地Y8-1井锆石U-Pb 定年检测报告[R]. 上海: 上海璟晟数据处理有限公司, 2019.
[24]	董树文, 张岳桥, 李海龙, 等. “燕山运动”与东亚大陆晚中生代多板块汇聚构造--纪念“燕山运动”90周年[J]. 中国科学: 地球科学, 2019, 49(3): 913-938.
[25]	QING Ye, MEI Lianfu, SHI Hesheng, et al. The Late Cretaceous tectonic evolution of the South China Sea area: An overview, and new perspectives from 3D seismic reflection data[J]. Earth-Science Reviews, 2018, 187: 186-204. DOI URL
[26]	Y9井花岗岩K-Ar 同位素年龄结果报告[R]. 湛江: 南海西部石油公司研究院, 1993.
[27]	琼东南盆地S34-A井错石U-Pb 定年分析[R]. 湛江: 中海油能源发展股份有限公司湛江南海西部研究院, 2016.
[28]	YOU Li, XU Shouli, MAU Xuelian. Reservoir characteristics and genetic mechanisms of the Mesozoic granite buried hills in the deep-water of the Qiongdongnan Basin, Northern South China Sea[J]. Acta Geologica Sinica, 2021, 95(1): 259-267. DOI URL
[29]	甘军, 张迎朝, 梁刚, 等. 琼东南盆地深水区烃源岩沉积模式及差异热演化[J]. 地球科学, 2019, 44(8): 2627-2635.
[30]	李增学, 宋广赠, 王东东, 等. 琼东南盆地渐新统煤系(扇)辫状河三角洲特征[J]. 地球科学, 2018, 43(10): 3471-3483.
[31]	张功成, 米立军, 屈红军, 等. 中国海域深水区油气地质[J]. 石油学报, 2013, 34(增): 1-14.
[32]	张功成, 屈红军, 刘世翔, 等. 边缘海构造旋回控制南海深水区油气成藏[J]. 石油学报, 2015, 36(5): 533-545. DOI
[33]	屈童, 高岗, 徐新德, 等. 三角洲-浅海沉积体系泥质沉积规律模拟实验--以琼东南盆地崖南凹陷为例[J]. 岩性油气藏, 2022, 34(1): 24-33.
[34]	杨希冰, 周杰, 杨金海, 等. 琼东南盆地深水区东区中生界潜山天然气来源及成藏模式[J]. 石油学报, 2021, 42(3): 283-292. DOI
[35]	GAN Jun, XIONG Shuling, LIANG Gang, et al. The influence of hydrothermal activity on the long-distance migration and accumulation of hydrocarbons: A case study from the Y8 area in the Songnan-Baodao sag of Qiongdongnan Basin[J]. Energies, 2022, 15(9): 1-19. DOI URL