Crude oil in the uplifts of the Huizhou depression, Pearl River Mouth Basin, South China Sea: Source and formation mechanisms

doi:10.13745/j.esf.sf.2021.9.19

Abstract

Abstract:

The Huizhou depression is the most important hydrocarbon-rich depression in the eastern Pearl River Mouth Basin, South China Sea. The uplifts, located in the southeastern margin of the Huizhou depression, are far from source rocks with no in-situ deposition of source rock strata. They are typical remotely sourced petroleum reservoirs, whose source and formation mechanisms are not yet known. This study systematically compared the biomarker compositions and isotopic characteristics between crude oil and source rock samples from the Huizhou depression. Combined with analysis of the fault-sand-unconformity migration pathways and blocking conditions, the Pathway software was used to simulate and analyze the three-dimensional hydrocarbon migration pathways, and the hydrocarbon accumulation process was analyzed in dynamic mode to overcome the limitations of static analysis. We suggest the source rock of the Wenchang formation is responsible for the crude oil in the uplifts. The crude oil samples were characterized by low C₁₉/C₂₃ tricyclic terpane ratio (<0.7), low C₂₀/C₂₃ tricyclic terpane ratio (<0.8), high C₂₇ rearranged sterane/C₂₇ regular sterane ratio (>0.25), low ETR value (<0.4), high 4-methylsterane/C₂₉ sterane ratio (BBB>4), and low bicadinane T/C₃₀ hopane ratio (<1). The simulated three-dimensional hydrocarbon migration pathways indicated that under the control of the Hui-Liu mid-ocean ridge, hydrocarbon generated in sag H26 of the Huizhou depression migrated to the Dongsha uplift along the dominant migration pathway and accumulated in the L11-1 oilfield in the uplifts far from the source rocks at the top of the mid-ocean ridge. The biomarker and carbon isotopic characteristics of crude oil samples from the uplifts were similar to those from other oilfields along the same predominant migration pathway. Therefore, we infer that the crude oil in the uplifts is predominantly sourced from the middle-deep lacustrine source rock of the Wenchang formation of sag H26.

Key words: Pearl River Mouth Basin, Huizhou depression, uplifts far from source rocks, characteristics of biomarkers, origin and source of oil and gas

CLC Number:

P597
P618.13

DUAN Wei, TIAN Jinqiang, LI Sanzhong, YU Qiang, CHEN Ruixue, LONG Zulie. Crude oil in the uplifts of the Huizhou depression, Pearl River Mouth Basin, South China Sea: Source and formation mechanisms[J]. Earth Science Frontiers, 2022, 29(5): 176-187.

Figures/Tables 15

Fig.1 Tectonic setting of the studied area. Modified after [22⇓⇓-25].

Fig.2 Map of the Huizhou depression showing the location and tectonic divisions. Modified after [26].

Fig.3 Generalized stratigraphic column for the Cenozoic succession in the Pearl River Mouth Basin. Modified after [27].

Fig.4 Variations of major biomarker parameters from different potential source rock intervals as a function of burial depth in the Huizhou depression

Fig.5 Correlation between various biomarker parameters of different source rock intervals in the Huizhou depression

Fig.6 Variations of physical property and group composition of oils with depth in the Huizhou depression

Fig.7 Illustrations showing the origin types of crude oil in the Huizhou depression

Fig.8 Distribution of oils with different origins in the Huizhou depression

Fig.9 Variation of biomarker parameters of oil from different sources with depth in the Huizhou depression

Fig.10 Variation of physical property of different sources oil with depth in the Huizhou depression

Fig.11 Structure map of the top Zhujiang formation and hydrocarbon reservoir section of the L11-1 oil field. Modified after [25].

Fig.12 Molded three-dimensional petroleum migration pathways in the Huixi semi-graben and its surrounding region

Fig.13 Ternary diagram showing the relative abundances of C27-C29 regular steranes in the oils from the L11-1 oil field and the Huizhou depression

Fig.14 Comparison of biomarkers between the oil from the L11-1 oil field and the Huizhou depression

Fig.15 Comparison of carbon isotopic characteristics between oil from the L11-1 oil field and the Huizhou depression

References 36

[1]	周兴熙. 成藏要素的时空结构与油气富集: 兼论近源富集成藏[J]. 石油与天然气地质, 2005, 26(6): 711-716.
[2]	赵文智, 张光亚, 王红军, 等. 中国叠合含油气盆地石油地质基本特征与研究方法[J]. 石油勘探与开发, 2003, 30(2): 1-8.
[3]	潘建国, 谭开俊, 王国栋, 等. 准噶尔盆地玛湖富烃凹陷源外近源油气藏内涵与特征[J]. 天然气地球科学, 2015, 26(增刊1): 1-10.
[4]	潘建国, 黄林军, 王国栋, 等. 源外远源油气藏的内涵和特征: 以准噶尔盆地盆1井西富烃凹陷为例[J]. 天然气地球科学, 2019, 30(3): 312-321.
[5]	陶士振, 李建忠, 柳少波, 等. 远源/次生油气藏形成与分布的研究进展和展望[J]. 中国矿业大学学报, 2017, 46(4): 699-714.
[6]	马小伟, 朱传真, 林玉祥, 等. 准噶尔盆地温压系统演化与油气远源成藏[J]. 石油实验地质, 2017, 39(4): 467-476.
[7]	HIGLEY D K, LEWAN M D, ROBERTS L N R, et al. Timing and petroleum sources for the Lower Cretaceous Mannville Group oil sands of northern Alberta based on 4-D modeling[J]. AAPG Bulletin, 2009, 93(2): 203-230. DOI URL
[8]	田立新, 施和生, 刘杰, 等. 珠江口盆地惠州凹陷新领域勘探重大发现及意义[J]. 中国石油勘探, 2020, 25(4): 22-30. DOI
[9]	史玉玲, 张向涛, 朱俊章, 等. 珠一坳陷近源及远源油气富集主控地质因素统计与油气运移物理模拟实验[J]. 中国海上油气, 2020, 32(5): 26-35.
[10]	郝鑫, 吴智平, 颜世永, 等. 珠江口盆地珠一坳陷浅层油气成藏模式研究[J]. 地质论评, 2017, 63(1): 113-121.
[11]	刘丽华, 李洪博, 彭辉界, 等. 珠江口盆地珠一坳陷隆控类油藏有利发育区带定量预测与评价[J]. 石油学报, 2015, 36(增刊 2): 134-144.
[12]	施和生, 代一丁, 刘丽华, 等. 珠江口盆地珠一坳陷油气藏地质特征与分布发育基本模式[J]. 石油学报, 2015, 36(增刊2): 120-133, 155.
[13]	龚晓峰, 何家雄, 莫涛, 等. 珠江口盆地珠一坳陷惠陆油区含油气系统与油气运聚成藏模式[J]. 天然气地球科学, 2015, 26(12): 2292-2303.
[14]	吴哲, 王文勇, 张忠涛, 等. 张扭性断裂带的生长过程与油气穿断运移评价: 以珠江口盆地恩平凹陷为例[J]. 海洋地质前沿, 2020, 36(1): 50-58.
[15]	田立新, 张向涛, 彭光荣, 等. 珠江口盆地阳江凹陷石油地质特征及成藏主控因素[J]. 中国海上油气, 2020, 32(1): 13-22.
[16]	杜晓东, 彭光荣, 吴静, 等. 珠江口盆地阳江东凹断层特征及其对油气成藏的影响[J]. 新疆石油地质, 2020, 41(4): 414-421.
[17]	何敏, 朱伟林, 吴哲, 等. 珠江口盆地新构造运动特征与油气成藏[J]. 中国海上油气, 2019, 31(5): 9-20.
[18]	代一丁, 牛子铖, 汪旭东, 等. 珠江口盆地陆丰凹陷古近系与新近系油气富集规律的差异及其主控因素[J]. 石油学报, 2019, 40(增刊1): 41-52.
[19]	李如山, 陈胜红, 胡兴豪, 等. 油气运移中断层精细刻画的优选方法: 以南海北部珠江口盆地惠西南地区为例[J]. 海洋地质前沿, 2017, 33(10): 57-63.
[20]	彭辉界, 庞雄奇, 李洪博, 等. 珠江口盆地珠一坳陷断裂控藏定量表征与有利勘探区预测[J]. 现代地质, 2016, 30(6): 1318-1328.
[21]	代一丁, 余秋华, 李洪博, 等. 珠江口盆地珠一坳陷烃源灶控藏临界条件与控藏特征[J]. 石油学报, 2015, 36(增刊2): 145-155.
[22]	施和生, 杜家元, 梅廉夫, 等. 珠江口盆地惠州运动及其意义[J]. 石油勘探与开发, 2020, 47(3): 447-461.
[23]	胡阳. 珠江口盆地珠一坳陷新生代盆地结构与成因演化[J]. 高校地质学报, 2019, 25(1): 81-92.
[24]	米立军, 张向涛, 庞雄, 等. 珠江口盆地形成机制与油气地质[J]. 石油学报, 2019, 40(增刊1): 1-10.
[25]	施和生, 舒誉, 杜家元, 等. 珠江口盆地古近系石油地质[M]. 北京: 地质出版社, 2017.
[26]	田巍, 何敏, 杨亚娟, 等. 珠江口盆地惠州凹陷北部边界断裂复合联接和转换[J]. 地球科学: 中国地质大学学报, 2015, 40(12): 2037-2051.
[27]	刘浩冉, 朱红涛, 施和生, 等. 珠江口盆地惠州凹陷迁移型层序特征及其意义[J]. 地球科学: 中国地质大学学报, 2015, 40(5): 840-850.
[28]	朱明, 张向涛, 黄玉平, 等. 珠江口盆地烃源岩特征及资源潜力[J]. 石油学报, 2019, 40(增刊1): 53-68.
[29]	BAO X H, JI Y B, HU Y, et al. Geochemical characteristics, origins, and model of lacustrine source rocks in the Zhu 1 depression, eastern Pearl River Mouth Basin, South China Sea[J]. AAPG Bulletin, 2017, 101(9): 1543-1564. DOI URL
[30]	袁才, 彭光荣, 温华华, 等. 珠江口盆地惠州凹陷恩平组源岩特征及勘探潜力[J]. 海洋地质与第四纪地质, 2017, 37(2): 149-159.
[31]	马明, 漆家福, 张远泽, 等. 珠江口盆地新生代沉降特征及其影响因素分析[J]. 中国地质, 2019, 46(2): 269-289.
[32]	邓运华. 渤海油区稠油成因探讨[J]. 中国海上油气, 2006, 18(6): 361-364, 371.
[33]	张水昌, 龚再升, 梁狄刚, 等. 珠江口盆地东部油气系统地球化学-Ⅰ: 油组划分、油源对比及混源油确定[J]. 沉积学报, 2004, 22(增刊1): 15-26.
[34]	王芳, 包建平, 朱翠山. 珠江口盆地惠州凹陷两类原油地球化学特征对比[J]. 地球科学与环境学报, 2016, 38(2): 235-244.
[35]	HU Y, HAO F, ZHU J Z, et al. Origin and occurrence of crude oils in the Zhu1 sub-basin, Pearl River Mouth Basin, China[J]. Journal of Asian Earth Sciences, 2015, 97: 24-37. DOI URL
[36]	HINDLE A D. Petroleum migration pathways and charge concentration: a three-dimensional model[J]. AAPG Bulletin, 1997, 81(9): 1451-1481.