琼东南盆地陵水北坡LS13-2区勘探思路与突破方向  

Philosophy and potential breakthroughs for hydrocarbon exploration in block LS13-2 on the northern slope of the Lingshui Sag,Qiongdongnan Basin

作　　者：周荔青[1] 江东辉[1] 杨鹏程[1] 张如凤 董鑫 桑亚迪 ZHOU Liqing;JIANG Donghui;YANG Pengcheng;ZHANG Rufeng;DONG Xin;SANG Yadi(Shanghai Offshore Petroleum Company,SINOPEC,Shanghai 200120,China)

机构地区：[1]中国石化上海海洋油气分公司,上海200120

出　　处：《石油与天然气地质》2024年第3期673-683,共11页Oil & Gas Geology

基　　金：中国石化集团公司科技项目(P23001)。

摘　　要：琼东南盆地陵水凹陷南坡已发现了中央峡谷千亿方级气田,证实了陵水凹陷为富生烃凹陷。而陵水凹陷北坡LS13-2区的岩性圈闭勘探虽然也取得了“点”上的突破,但“见气不见田”,勘探效果不佳。为了明确该地区的油气富集规律和有利区带,以含油气盆地分析为基础,聚焦关键成藏要素,提出了新的勘探思路,并明确了有利成藏区带。研究结果表明:工区成藏条件整体有利,具备“充足烃源、规模储层、高效输导、整体保存”的大-中型油气田形成基础,但对于中新统岩性圈闭勘探来讲,也存在“烃源岩主排烃期早于圈闭定型期,断层垂向输导能力低”的不利因素,据此建立了“早期成藏、岩性圈闭、断-砂输导”三元勘探评价要素,并评价认为探区西部断坡海底扇带具备“原生油气藏、规模岩性圈闭、断-砂高效输导”的有利成藏条件,为最有利成藏区带。The Central Canyon gas field,with reserves exceeding 100 billion cubic meters,has been discovered on the southern slope of the Lingshui Sag in the Qiongdongnan Basin,confirming the hydrocarbon-rich nature of this sag.Despite local breakthroughs,lithological reservoir exploration in block LS13-2 on the northern slope of the Lingshui Sag has yielded merely gas shows rather than substantial reserves,indicating unsatisfactory exploration outcomes.This study aims to determine the hydrocarbon accumulation patterns and play fairways in the block.By analyzing petroliferous basins and critical factors controlling hydrocarbon accumulation,we propose a novel philosophy of hydrocarbon exploration and identify paly fairways for hydrocarbon accumulation.The results indicate that block LS13-2 exhibits generally favorable conditions for hydrocarbon accumulation,which lay the foundations for the formation of large-to medium-sized oil and gas fields characterized by sufficient hydrocarbon sources,large-scale reservoirs,efficient carrier systems,and generally excellent preservation conditions.Nevertheless,the exploration of the Miocene lithologic traps faces challenges due to unfavorable factors such as the main hydrocarbon expulsion stage of source rocks occurring earlier than trap formation and the low vertical hydrocarbon transport capability of faults.Accordingly,we develop a three-dimension exploration assessment methodology consisting of early hydrocarbon accumulation,lithologic traps,and fault-sand body conduit system.The assessment results indicate that the submarine fan zone of the western ramp features favorable hydrocarbon accumulation conditions encompassing primary hydrocarbon reservoirs,large-scale lithologic traps,and efficient fault-sand body carrier systems,establishing this zone as an optimal play fairway.

关 键 词：富集规律 成藏条件 有利区带 梅山组 陵水凹陷 琼东南盆地 

分 类 号：TE122.3[石油与天然气工程—油气勘探]