PDF(9165 KB)
琼东南盆地断阶带地貌控制下的辫状河三角洲发育特征——以宝岛凹陷北坡渐新统陵水组三段为例
邓孝亮, 汪紫菱, 尤丽, 詹冶萍, 周晨
海相油气地质 ›› 2025, Vol. 30 ›› Issue (1) : 30-40.
PDF(9165 KB)
PDF(9165 KB)
琼东南盆地断阶带地貌控制下的辫状河三角洲发育特征——以宝岛凹陷北坡渐新统陵水组三段为例
Development characteristics of braided river delta under geomorphic control of fault step zone in Qiongdongnan Basin: taking the 3rd member of Oligocene Lingshui Formation in the northern slope of Baodao Sag as an example
琼东南盆地深层渐新统陵水组是南海海域下一步勘探的重点。基于岩心、测录井和三维地震资料，系统解剖了琼东南盆地宝岛凹陷北部陵水组沉积特征，明确陵水组可细分为2个三级层序，其中陵三段沉积为一个完整的三级层序，发育低位、海侵和高位体系域。控凹的F12断层差异活动形成的断层同向转换带以及转换斜坡控制着神狐隆起和海南隆起物源的注入，并控制了陵三段规模各异的西、东多支大型辨状河三角洲群的发育。断阶带在低位晚期和高位期主要发育辫状河三角洲前缘水下分流河道沉积，砂体厚度大，粒度较粗，分选较好，物性较好，为优质储层发育层段。由此建立宝岛凹陷北部断阶带陵三段深水盆地多级断裂控物源，转换断阶控砂体展布的发育模式。陵三段大型三角洲前缘水下分流河道优质储集体直接覆盖于崖城组烃源岩之上，与沟通烃源岩的断裂形成有利输导体系，又被后期拗陷期沉积的厚层海侵浅海泥岩覆盖，形成的优质储盖组合和输导体系是形成宝岛凹陷大型气田的关键。
Qiongdongnan Basin, a passive continental deep-water basin in the north of the South China Sea, is an important natural gas base in China. The deep Oligocene Lingshui Formation in Qiongdongnan Basin represent a primary target for forthcoming exploration in the South China Sea, however, due to limited exploration efforts, the sedimentary system of the Lingshui Formation remains inadequately characterized. Based on core, logging and 3D seismic data, the sedimentary characteristics of Lingshui Formation in northern slope of Baodao Sag, Qiongdongnan Basin are systematically dissected. It is clear that Lingshui Formation can be subdivided into two third-order sequences. The sedimentation of the 3rd member of Lingshui Formation is a complete three-order sequence with low, transgressive and high system domains. Under the control of the fault co directional transition zone and transition slope formed by the differential activity of F12 fault, several large differentiated river delta groups of different scales in the west and east are developed in the 3rd member of Lingshui Formation. The fault step zone mainly developed the underwater distributary channel of braided river delta front in the late low and high system tracts, and it is a high-quality reservoir development interval with the thickness of sand body being large, the particle size being coarser, the separation being better, and the physical property being better. Therefore, the development model of multistage fault-controlled material source and transition fault-controlled sand body distribution of the 3rd member of Lingshui Formation in the northern fault step zone of Baodao Sag is established. The high quality reservoir of large-scale delta distributary channel of the 3rd member of Lingshui Formation directly covers the source rock of Yacheng Formation and forms a favorable transport system with source rock-linked fault. And it is covered by thick transgressive shallow-sea mudstone deposited in late depression period. High-quality reservoer-cap combination and transport system are the key to forming large gas fields in Baodao Sag, and are worth of more attention in the future exploration.
辫状河三角洲 / 断阶带 / 陵水组三段 / 古近系 / 宝岛凹陷 / 琼东南盆地
braided river delta / fault step zone / the 3rd member of Lingshui Formation / Paleogene / Baodao Sag / Qiongdongnan Basin
| [1] |
谢玉洪. 南海北部陆缘盆地深水区油气勘探新认识及攻关方向[J]. 天然气工业, 2024, 44(1): 13-25.
|
| [2] |
屈红军, 张功成, 孙晓晗, 等. 中国深水盆地油气勘探及成藏研究进展: 以中国南海北部为例[J]. 西北大学学报(自然科学版), 2022, 52(6): 1028-1043.
|
| [3] |
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.
琼东南盆地是中国近海的一个在浅水区、深水区、超深水区均发现煤型大气田的盆地，探讨其天然气地质特征及勘探新领域具有重要的理论和实际意义。笔者基于区域地质、地震、钻井、地球化学测试等数据分析了琼东南盆地的成藏特征和勘探潜力。研究结果表明：琼东南盆地在崖城组沉积期具有"两隆两坳"的构造格局，崖城组的煤型烃源岩（包括煤系烃源岩和陆源海相烃源岩）是主要的烃源岩，以渐新统崖城组（扇）三角洲为中心的煤型烃源岩的生烃灶，主要沿北部坳陷北缘、中央坳陷南缘和北缘呈串珠状分布；北部坳陷北缘的煤型烃源岩的成熟度低，未进入大量生气阶段；中央坳陷南缘和北缘的煤型烃源岩均已成熟，且已进入大量生气阶段；每个（扇）三角洲发育的煤系烃源岩及其周边的陆源海相泥岩均为1个富气生烃灶。受渐新世煤型烃源岩的生烃灶控制，形成了中央坳陷南缘和北缘2个大型气聚集带；气聚集带中的凸起、断阶带、缓坡带、凹中浊积体等圈闭是煤型天然气的主要勘探领域，勘探前景巨大，天然气资源量预计超过2×10<sup>12</sup>m<sup>3</sup>。
In China, Qiongdongnan Basin is the only place where large coal type gas fields have been discovered in shallow water, deep water, and ultra-deep water areas. Therefore, it is of important theoretical and practical significance to explore the geological characteristics of natural gas and new exploration fields in the basin. Based on regional geological, seismic, drilling, and geochemical testing, the paper analyzes the accumulation characteristics and exploration potentials of Qiongdongnan Basin. The results indicate that a tectonic framework of "two uplifts and two subbasins" was formed during the deposition period of Yacheng Formation in Qiongdongnan Basin. The coal-type source rocks (including coal-measure source rocks and terrestrial marine source rocks) of Yacheng Formation are the major source rocks, and the source kitchen of coal-type source rocks in the (fan) delta of the Oligocene Yacheng Formation mainly shows a bead-like distribution along the northern margin of the northern depression, the southern and northern margins of the central depression belt. The maturity of coal-type source rocks in the northern margin of the northern depression is low and has not come up to the main gas generation stage. The coal-type source rocks at the southern and northern margins of the central depression belt are mature and have entered the main gas generation stage. Coal-measure source rocks and the surrounding terrestrial marine mudstones developed in each (fan) delta are one source kitchen. As controlled by the source kitchen of the Oligocene coal-type source rocks, two large gas accumulation belts were formed at the southern and northern margins of the central depression belt. The main exploration areas for coal-type natural gas include uplifts, step-fault belts, gentle slope belts, and turbidite bodies inside sags in the gas accumulation belt, showing great exploration prospects, and the natural gas resources are expected to exceed 2×10<sup>12</sup>m<sup>3</sup>.
|
| [4] |
吴克强, 解习农, 裴健翔, 等. 超伸展陆缘盆地深部结构及油气勘探意义: 以琼东南盆地为例[J]. 石油与天然气地质, 2023, 44(3): 651-661.
|
| [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.
|
| [6] |
尤丽, 吴仕玖, 代龙, 等. 琼东南盆地乐东—陵水凹陷梅山组海底扇高温超压储层成岩-孔隙演化[J]. 海相油气地质, 2024, 29(3): 280-290.
|
| [7] |
刘子玉, 贾万丽, 李建平, 等. 浊积扇沉积构成及主要单元储层差异:以琼东南盆地梅山组为例[J]. 地质科学, 2024, 59(5): 1268-1279.
|
| [8] |
李建平, 熊连桥, 黄琪斐, 等. 琼东南盆地梅山组浊积扇分类及其勘探意义[J]. 油气地质与采收率, 2023, 30(6): 1-12.
|
| [9] |
付超, 谢玉洪, 王晖, 等. 深水峡谷复合浊积砂体内隔夹层发育类型与沉积成因: 以琼东南盆地中央峡谷为例[J]. 天然气工业, 2023, 43(5): 23-33.
|
| [10] |
付超, 谢玉洪, 赵雨初, 等. 深水峡谷上游复合浊积砂岩储层类型及其展布规律: 以琼东南盆地中央峡谷陵水气田为例[J]. 石油与天然气地质, 2024, 45(2): 516-529.
|
| [11] |
徐长贵, 吴克强, 裴健翔, 等. 超深水超浅层天然气富集机理与成藏模式: 以琼东南盆地陵水36-1气田为例[J]. 石油勘探与开发, 2025, 52(1):44-56.
基于琼东南盆地油气勘探实践与油气地质研究新进展，综合地震、测井、钻井、岩心、井壁取心及地球化学等新资料，以陵水36-1气田为例，对超深水超浅层天然气田的气源、储-盖条件、圈闭类型、运聚特征、富集机理与成藏模式开展系统研究。研究表明：①琼东南盆地超深水超浅层天然气成因类型包括热成因气和生物气，以热成因气为主；②储层主要为第四系深水海底扇砂岩；③盖层类型有深海泥岩、块体流泥岩及含水合物地层；④圈闭类型以岩性圈闭为主，也发育构造-岩性圈闭；⑤运移通道包括断层、气烟囱、裂隙带等垂向输导通道及大型砂体、不整合面等侧向输导层，构成单一或者复合输导格架。提出超深水超浅层天然气“深浅双源供烃、气烟囱-海底扇复合输导、深海泥岩-块体流泥岩-含水合物地层三元封盖、晚期动态成藏、脊线规模富集”的天然气成藏新模式。研究取得的新认识对下步深水超浅层及相关领域或地区的油气勘探具有借鉴和启示意义。
|
| [12] |
裴健翔, 王宇. 琼东南盆地深水区第四系超浅层大型气藏盖层类型及封盖机理[J]. 地球科学, 2025, 50(1):144-157.
|
| [13] |
裴健翔, 罗威, 呙诗阳, 等. 琼东南盆地宝岛凹陷南部渐新统陵水组三段三角洲的发现及石油地质意义[J]. 石油勘探与开发, 2024, 51(2): 299-310.
基于琼东南盆地三维地震资料及钻井获取的岩性、电性、薄片及测年等分析测试数据，开展宝岛凹陷南部断阶带渐新统陵水组三段（简称陵三段）源-汇体系特征及源-汇耦合定量分析等研究。研究表明：①陵三段沉积期YL10剥蚀区发育东、西2大物源水系，在宝岛凹陷南部形成了2大优势输砂通道及2个三角洲朵叶体，整体具有西大东小的特征，可划分为初始期、昌盛期、间歇期和回春期4个演变阶段；②综合三角洲砂体发育期次、展布面积、碾平厚度及不同类型母岩区面积、成砂系数等参数进行源-汇耦合定量计算，结果显示研究区具备形成规模储集体的物质基础；③钻井揭示陵三段三角洲沉积以细砂岩为主，砂岩总厚度为109~138 m，最大单层厚度为15.5~30.0 m，砂地比为43.7%~73.0%，不同断阶间储层物性差异明显；④断阶带多期隆升背景下小物源区规模三角洲发育模式揭示幕式隆升提供充足的物源供给，物源水系及流域面积控制砂体的规模，多级活动断阶控制砂体的输送通道，局部断槽控制砂体的侧向推进方向。陵三段三角洲砂体与断块耦合形成多类型圈闭，成为凹陷南部重要的勘探突破口和新领域，有望为盆地内其他构造背景相似区域油气勘探及储层研究提供借鉴。
|
| [14] |
唐武, 谢晓军, 熊连桥, 等. 琼东南盆地深层源汇系统特征及富砂性预测:以松南低凸起中段陵三段为例[J]. 海洋地质与第四纪地质, 2024, 44(4): 123-133.
|
| [15] |
童亨茂, 范彩伟, 童传新, 等. 琼东南盆地宝岛变换带的特征、类型及其成因机制[J]. 石油与天然气地质, 2015, 36(6): 897-905.
|
| [16] |
赵海涛, 童亨茂. 琼东南盆地北部地区变换带构造特征及地质意义[J]. 中国石油大学学报(自然科学版), 2021, 45(2): 11-20.
|
| [17] |
廖计华, 王华, 吕明, 等. 琼东南盆地深水区松南—宝岛凹陷同沉积断裂活动及其对沉积充填的控制[J]. 中国矿业大学学报, 2016, 45(2): 336-346.
|
| [18] |
钟佳, 杨希冰, 朱沛苑, 等. 琼东南盆地宝岛—长昌凹陷陵水组储层差异演化特征[J]. 地球科学, 2019, 44(8): 2665-2676.
|
| [19] |
邓勇, 裴健翔, 胡林, 等. 南海西部海域宝岛21-1气田的发现与成藏模式[J]. 中国海上油气, 2022, 34(5): 13-22.
|
| [20] |
尤丽, 权永彬, 庹雷, 等. 琼东南盆地深水区宝岛21-1气田天然气来源及输导体系[J]. 石油与天然气地质, 2023, 44(5): 1270-1278.
|
| [21] |
徐长贵. 中国近海油气勘探新进展与勘探突破方向[J]. 中国海上油气, 2022, 34(1): 9-16.
|
| [22] |
徐长贵, 尤丽. 琼东南盆地松南—宝岛凹陷北坡转换带特征及其对大中型气田的控制[J]. 石油勘探与开发, 2022, 49(6): 1061-1072.
基于新采集三维地震与钻井资料分析，系统解剖宝岛凹陷地质结构及其断裂体系，开展转换断阶带特征及其对天然气成藏的控制作用研究。研究结果表明：宝岛凹陷发育北部断阶带、中部凹陷带与南部斜坡带，其中，北部断阶带自西向东发育宝岛B、A、C等多个转换断阶带，控制宝岛凹陷烃源岩、圈闭、储集层、油气运移及烃类气富集。转换带主干断裂在渐新世早期崖城组沉积期的活动性控制生烃灶与生烃潜力，自西向东活动性增强且距离物源区更近，烃源岩厚度、三角洲规模呈增大趋势，发育多个生烃洼陷；主干断裂在张扭背景下发生局部挤压，形成大型鼻状构造背景下的复合型圈闭，且向东宝岛A、宝岛C圈闭规模大于宝岛B圈闭；多级断阶控制隆起区物源碎屑注入形成大型三角洲砂体，宝岛A转换带F12断裂中西段同向转换带和东段缓坡段控制两大物源碎屑注入，形成西支、东支等多个三角洲朵叶体；主干断裂控制形成的大型构造脊紧邻生烃中心，具有高效运聚特征；主干断裂组合方式、活动时间与天然气充注期次的良好匹配，控制烃类气富集。宝岛A转换带紧邻生烃洼陷宝岛27、25、21洼，发育神狐隆起物源供给的大型辫状河三角洲沉积，具有大型构造脊高效汇聚及主干断裂平行组合且停止活动时间早的特征，是烃类气优势汇聚区，实钻发现厚层优质气层，获得宝岛凹陷首个大型气田宝岛21-1的发现，证实松南—宝岛北部转换带成藏条件好，向东转换断阶带拓展勘探潜力大。
|
| [23] |
杨金海, 杨希冰, 周杰, 等. 琼东南盆地深水区松南—宝岛凹陷反转构造带发育特征及油气地质意义[J]. 海洋学报, 2019, 41(5): 97-106.
|
| [24] |
李增学, 刘莹, 李晓静, 等. 琼东南盆地古近纪泥炭沼泽破坏与重建作用对煤型源岩物质形成的控制[J]. 石油与天然气地质, 2022, 43(6): 1309-1320.
|
| [25] |
张远泽, 漆家福, 吴景富. 南海北部新生代盆地断裂系统及构造动力学影响因素[J]. 地球科学, 2019, 44(2): 603-625.
|
| [26] |
邓孝亮, 张迎朝, 陆江, 等. 文昌B凹陷北坡珠海组潮汐沉积特征及演化[J]. 沉积学报, 2020, 38(6): 1313-1326.
|
/
| 〈 |
|
〉 |
