珠江口盆地西江凹陷番禺4洼古近系勘探重大发现及其意义
Major discoveries and significance of hydrocarbon exploration in the Paleogene reservoirs of Panyu4 subsag,Xijiang sag,Pearl River Mouth Basin
徐长贵 1高阳东 1刘军 2彭光荣 2邱欣卫 2张晓钊 2贾培蒙2
作者信息
- 1. 中国海洋石油有限公司 北京 100010
- 2. 中海石油(中国)有限公司深圳分公司 广东深圳 518054;中海石油深海开发有限公司 广东深圳 518054
- 折叠
摘要
珠江口盆地西江凹陷南部的番禺4洼是已证实的富生烃洼陷,早期的油气勘探发现主要分布在中新统珠江组以上的中—浅部层系(埋深小于3 000m).近期,中—深层古近系的油气勘探获得重大突破,在番禺10-6构造带渐新统珠海组和始新统恩平组高含砂率地层中发现了大—中型油田.为进一步指导番禺4洼古近系油气勘探,综合高精度三维地震、钻井和分析化验资料,对番禺4洼古近系砂岩油藏形成的烃源条件、储-盖组合、断层圈闭有效性及油气成藏模式等开展了系统研究,总结了珠江口盆地古近系富砂层系大—中型油气田的形成条件及勘探方向.研究结果表明:文昌组中广泛发育的半深湖—深湖亚相优质烃源岩是深层油气规模聚集的烃源基础;恩平组、珠海组均发育辫状河三角洲砂岩,分别与湖(海)泛泥岩、钙质砂岩构成了两类优质储-盖组合;伸展-走滑背景下的张扭断裂增压区和断裂带上盘的钙质胶结作用有利于富砂层段断块圈闭的侧向封堵;与构造带相邻的主通源断裂决定了油气的近距离高效优势汇聚.研究成果有效地指导了番禺10-6构造带大—中型油气田的发现,实现了番禺4洼古近系新层系的勘探突破,揭示了珠江口盆地富生烃洼陷古近系的勘探潜力,对珠江口盆地其他地区古近系高含砂率地层的勘探具有重要参考意义.
Abstract
Panyu4 subsag in the south of Xijiang sag in Pearl River Mouth Basin is proved to be rich in hydrocarbons.The early oil-gas exploration discoveries were mainly distributed in the middle and shallow strata above the Miocene Zhujiang Formation(buried depth less than 3 000 m).Recently,a major breakthrough has been made in the oil-gas exploration for Paleogene reservoirs in the middle and deep layers.Large and medium oilfields have been found in sand-rich strata of the Oligocene Zhuhai Formation and the Eocene Enping Formation in the Panyu10-6 structural belt.To further guide oil-gas exploration in the Eocene reservoirs of Panyu4 subsag,based on high-precision three-dimensional seismic,drilling and analytical data,this paper systematically studies the hydrocarbon source conditions,reservoir-cap assemblage,fault trap effectiveness and hydrocarbon accumulation mode of the Paleogene sandstone reservoirs in Panyu4 subsag,and summarizes the formation conditions and exploration direction of large and medium oil-gas fields in the Paleogene sand-rich strata in Pearl River Mouth Basin.The research results show that the extensive development of high-quality semi-deep to deep lake subfacies source rocks in Wenchang Formation provides a material basis for the large-scale accumulation of deep oil and gas.Braided river delta sandstones are developed in Enping Formation and Zhuhai Formation,which constitute two types of high-quality reservoir-cap assemblages with lake(sea)flooding mudstone and calcareous sandstone,respectively.Under the background of extension and strike-slip,the pressurization zone of transtensional fault and the calcareous cementation on the hanging wall of fault zone are beneficial to the lateral sealing of fault-block traps in the sand-rich strata.The main source faults adjacent to the structural belt determine the high-efficiency accumulation of oil and gas in short distance.The research results have effectively guided the discovery of large-medium oil-gas fields in Panyu10-6 structural belt,realized the exploration breakthrough in the new Paleogene strata of Panyu4 subsag,and revealed the exploration potential of the Paleogene hydrocarbon-rich subsag in Pearl River Mouth Ba-sin,providing important reference for the exploration of the Paleogene sand-rich strata in other areas of Pearl River Mouth Basin.
关键词
珠江口盆地/西江凹陷/番禺4洼/古近系/高含砂率地层/勘探突破/大—中型油田Key words
Pearl River Mouth Basin/Xijiang sag/Panyu4 subsag/Paleogene/sand-rich stratum/exploration breakthrough/large and medium oilfield引用本文复制引用
基金项目
中国海洋石油集团有限公司"十四五"科技重大项目(KJGG2022-0403)
中海石油(中国)有限公司前瞻基础研究项目(KJQZ-2023-2001)
中海石油(中国)有限公司重大生产性科研项目(SCKY-2023-SZ-02)
出版年
2024
NETL
NSTL
万方数据