Exploration breakthrough and enlightenment of the Yacheng Formation in the Yacheng 13-1 Low Uplift, Qiongdongnan Basin

doi:10.3969/j.issn.1006-6535.2025.04.004

Abstract

Abstract: In recent years, significant breakthroughs have been made in natural gas exploration of the Yacheng Formation in the Yacheng 13-1 Gasfield. To further summarize geological understanding of Yacheng Formation accumulation and promote field expansion and reserve growth, based on new drilling, seismic, and analytical test data, the geological conditions for accumulation in the Yacheng Formation of the Yacheng 13-1 Gasfield were systematically analyzed. The results indicate that the Yacheng Formation reservoirs in the Yacheng 13-1 Gasfield are mainly braided river delta channel sandstones and conglomerates, with large-scale sand body development and good physical properties. The structural top is covered by Meishan Formation mudstone, and the updip direction of the flank is segmented by mudstone barriers, forming a good reservoir-seal combination, representing a typical structural-stratigraphic trap. Since the trap is located at the structural high of the Yacheng Formation, it benefits from dual hydrocarbon supply from source rocks in the Yanan Sag and the Yinggehai Basin, providing excellent conditions for hydrocarbon migration and accumulation. The breakthrough of Yacheng Formation natural gas in Well YC13-10-C also confirms the characteristics of differential enrichment and three-dimensional accumulation of the Yacheng Formation in the Yacheng 13-1 Gasfield. Therefore, around existing gas-bearing structures or gas reservoirs, conducting three-dimensional exploration research on structural-stratigraphic traps from high to low positions will be an important direction for the next step of rolling natural gas exploration within this area and similar gas reservoirs. This understanding has certain guiding significance for the next step of exploration in the Yacheng 13-1 Gasfield.

Key words: exploration breakthrough, Yacheng Formation, structural-stratigraphic trap, Yacheng 13-1 Gasfield, Qiongdongnan Basin

CLC Number:

TE122.1

REN Lijuan, HE Xiaohu, ZHANG Yazhen, XIE Chao, WANG Lifeng, CAI Quansheng. Exploration breakthrough and enlightenment of the Yacheng Formation in the Yacheng 13-1 Low Uplift, Qiongdongnan Basin[J]. Special Oil & Gas Reservoirs, 2025, 32(4): 33-40.

References

[1] 吴克强,曾清波,李宏义,等.南海北部天然气成藏规律与勘探领域[J].中国海上油气,2022,34(5):23-35.
WU Keqiang,ZENG Qingbo,LI Hongyi,et al.Accumulation laws and exploration fields of natural gas in northern South China Sea[J].China Offshore Oil and Gas,2022,34(5):23-35.
[2] 吴克强,裴健翔,胡林,等.莺歌海盆地大—中型气田成藏模式及勘探方向[J].石油学报,2023,44(12):2200-2216.
WU Keqiang,PEI Jianxiang,HU Lin,et al.Accumulation model and exploration direction of medium-large gas fields in Yinggehai Basin[J].Acta Petrolei Sinica,2023,44(12):2200-2216.
[3] 侯明才,何小胡,金秋月,等.琼东南盆地中生代潜山成储主控因素及分布规律[J].石油与天然气地质,2023,44(3):637-650.
HOU Mingcai,HE Xiaohu,JIN Qiuyue,et al.Factors controlling the formation and distribution of Mesozoic buried hill reservoirs in the Qiongdongnan Basin[J].Oil & Gas Geology,2023,44(3):637-650.
[4] 张功成,纪沫,陈莹,等.琼东南盆地“气聚集带”的成藏特征与勘探潜力[J].石油学报,2024,45(1):226-240.
ZHANG Gongcheng,JI Mo,CHEN Ying,et al.Accumulation characteristics and exploration potentials of gas accumulation belt in Qiongdongnan Basin[J].Acta Petrolei Sinica,2024,45(1):226-240.
[5] 尤丽,江汝锋,龚宇,等.琼东南盆地深水海底扇岩性圈闭成藏主控因素与勘探突破[J].地球科学,2024,49(2):749-758.
YOU Li,JIANG Rufeng,GONG Yu,et al.Main controlling factors of accumulation and exploration breakthrough of deep-water submarine fan lithologic trap in the Qiongdongnan Basin[J].Journal of Earth Science,2024,49(2):749-758.
[6] 张功成,贾庆军,王万银,等.南海构造格局及其演化[J].地球物理学报,2018,61(10):4194-4215.
ZHANG Gongcheng,JIA Qingjun,WANG Wanyin,et al.On tectonic framework and evolution of the South China Sea[J].Chinese Journal of Geophysics,2018,61(10):4194-4215.
[7] 谢玉洪,童传新,范彩伟,等.琼东南盆地断裂系统特征与演化[J].大地构造与成矿学,2015,39(5):795-807.
XIE Yuhong,TONG Chuanxin,FAN Caiwei,et al.Characteristics and evolution of fault system in Qiongdongnan Basin[J].Geotectonica et Metallogenia,2015,39(5):795-807.
[8] 张焱,熊小峰,唐历山,等.琼东南盆地新生代伸展过程及其区域性差异定量研究[J].海相油气地质,2020,25(4):369-375.
ZHANG Yan,XIONG Xiaofeng,TANG Lishan,et al.Quantitative study on Cenozoic extension process and regional differences in Qiongdongnan Basin[J].Marine Origin Petroleum Geology,2020,25(4):369-375.
[9] REN Jianye,LEI Chao.Tectonic stratigraphic framework of the Yinggehai-Qiongdongnan Basins and its implication for tectonics province division in South China Sea[J].Chinese Journal of Geophysics,2011,54(6):1124-1137.
[10] 王真真,王世朝,李安琪,等.红河断裂活动对琼东南盆地环崖南凹陷构造-沉积-成藏的影响[J].海相油气地质,2021,26(1):51-59.
WANG Zhenzhen,WANG Shichao,LI Anqi,et al.Strike slip activity of Red River fault and its tectonic-sedimentary response and influence on hydrocarbon accumulation around Ya′nan Sag in the west of Qiongdongnan Basin[J].Marine Origin Petroleum Geology,2021,26(1):51-59.
[11] 周杰,杨希冰,甘军,等.琼东南盆地深水区断裂对沉积充填的控制作用[J].特种油气藏,2017,24(2):75-79.
ZHOU Jie,YANG Xibing,GAN Jun,et al.Controlling effect of faulting on sedimentary fill in the deep water areas,the Qiongdongnan Basin[J].Special Oil & Gas Reservoirs,2017,24(2):75-79.
[12] 廖计华,王华,肖军,等.琼东南盆地古近纪幕式裂陷及构造、层序和沉积的综合响应过程[J].吉林大学学报(地球科学版),2012,42(4):970-983.
LIAO Jihua,WANG Hua,XIAO Jun,et al.Episodic rifting and integrated response process of tectonic,sequence stratigraphy and sedimentary filling in Paleogene of Qiongdongnan Basin,South China Sea[J].Journal of Jilin University(Earth Science Edition),2012,42(4):970-983.
[13] YANG Yunliu,HE Yunlong,XIE Xinong,et al.Zircon U-Pb age constraints on the provenance and response to tectonics:Lower Oligocene of the western Qiongdongnan Basin,South China Sea[J].Marine and Petroleum Geology,2023,148:106059.
[14] LIU Kun,CHENG Peng,FAN Caiwei,et al.Evolutions of sedimentary facies and paleoenvironment and their controls on the development of source rocks in continental margin basins:a case study from the Qiongdongnan Basin,South China Sea[J].Petroleum Science,2023,20(5):2648-2663.
[15] 侯读杰,吴克强,尤丽,等.琼东南盆地陆源海相烃源岩有机质富集机理[J].石油与天然气地质,2024,45(1):31-43.
HOU Dujie,WU Keqiang,YOU Li,et al.Organic matter enrichment mechanisms of terrigenous marine source rocks in the Qiongdongnan Basin[J].Oil & Gas Geology,2024,45(1):31-43.
[16] 刘莹,刘海燕,杨海长,等.琼东南盆地古近纪成煤沉积体系类型及特征[J].石油与天然气地质,2019,40(1):142-151.
LIU Ying,LIU Haiyan,YANG Haichang,et al.Types and characteristics of Paleogene coal-forming sedimentary systems in Qiongdongnan Basin[J].Oil & Gas Geology,2019,40(1):142-151.
[17] 李莹,张功成,吕大炜,等.琼东南盆地崖城组沉积特征及成煤环境[J].煤田地质与勘探,2011,39(1):1-5.
LI Ying,ZHANG Gongcheng,LYU Dawei,et al.Depositional characteristics and coal forming environment of Yacheng Formation,Qiongdongnan Basin[J].Coal Geology & Exploration,2011,39(1):1-5.