Abstract: Pearl River Mouth Basin has still been in the stage of medium- and low-degree oil and gas exploration. In recent years, more efforts have been put on the research and evaluation of new fields in the basin and achieved a series of exploration results. We have realized new discoveries from multiple fields and types of exploration in hydrocarbon-rich depressions, i.e., the Paleogene of Wenchang A depression, Lufeng depression, Huizhou depression and Panyu 4 depression, the paleo-buried hill in Huizhou depression, as well as new depressions including Yangjiang East depression, and Kaiping depression. This has achieved large-scale reserves, thus reinforcing the reserve base for the stable development of oil fields in the east and west of South China Sea. It is clarified that the large-scale pressurization fault transitional slope zone in a fault basin indicates the main direction of exploration for large- and medium-sized oil and gas fields, thus changing the fact that no large scale reserves had been discovered in Wenchang A depression for many years. We innovatively proposed an understanding of hydrocarbon accumulation, i.e., "early fault transportation, small-scale source sink system and transformation zone controlling sand, and accumulations controlled by uplifts between depressions", guiding the discovery of the Paleogene high-yield oilfield group in the southern Lufeng sag. The establishment of exploration techniques for the fan delta-braided river delta sedimentary system has promoted the discovery of oilfield group on 10⁸t scale in the Palaeogene steep slope in the southwestern Huizhou depression. Deepening the research on reservoir-seal combination and petroleum entrapment in sand-rich series can contribute to the exploration and discovery of large- and medium-sized oil and gas fields in the new series of strata in Enping Formation of Panyu 4 depression. Innovatively establishing a model of diagenesis-mountain formation-reservoir formation-hydrocarbon accumulation for magmatic arcs in Mesozoic continental margins has guided the southwestern Huizhou depression to achieve a large-scale commercial breakthrough in the paleo-buried hills. The significant discovery of the oilfields group in East Yangjiang sag-North Enping sag is promoted by innovating the new mechanism of strong extension and weak strike slip controlling basin and hydrocarbons. Moreover, the innovative proposal of basin formation mechanism in the mode of "detachment-metamorphic core complex" is expected to form an oilfield group on a billion ton scale in the southern Kaiping belt. We have gradually developed new exploration fields such as Paleogene strata, buried hills, and new depressions and multiple technology series in Pearl River Mouth Basin, providing a solid technical support for the continuous increase of reserves and production in the eastern and western oilfields of South China Sea and opening up new prospects for new fields and new types of exploration. The resource evaluation results show that the remaining resources of the Paleogene system in hydrocarbon -rich depressions and buried hills in Pearl River Mouth Basin are mainly distributed in Huizhou 26 depression, Wenchang A depression, and etc. The crude oil resources are most abundant in the periphery of the Yangjiang-Yitong'ansha fault zone and the new depressions around Huizhou-Lufeng area.

Key words: hydrocarbon-rich depression, Paleogene, paleo-buried hill, new depression, resource potential, Pearl River Mouth Basin

摘要： 珠江口盆地油气勘探尚处于中、低勘探程度阶段，近年来，盆地加大了新领域的研究与评价力度，取得了一系列勘探成果。在富烃洼陷文昌A凹、陆丰凹陷、惠州凹陷、番禺4洼的古近系，富烃洼陷惠州凹陷的古潜山，新洼陷阳江东凹与开平凹陷等实现了多领域、多类型勘探新发现，落实了规模储量，为南海东、西部油田稳定发展夯实了储量基础。明确断陷盆地的大型增压型断裂转换斜坡带是大中型油气田勘探的主要方向，打破了文昌A凹多年未有规模发现的局面；创新提出"早断输导、小型源-汇体系及转换带控砂，洼间隆控藏"成藏认识，指导了陆丰南古近系高产能油田群的发现；建立扇三角洲—辫状河三角洲沉积体系勘探技术系列，推动了惠西南古近系陡坡带亿吨级油田群的发现；深化富砂层系储-盖组合及成藏研究，助力番禺4洼恩平组新层系取得大中型油气田勘探发现；创新建立中生代陆缘岩浆弧成岩-成山-成储-成藏模式，指导惠西南取得了古潜山规模商业突破；创新强伸展-弱走滑控盆控烃新机制，推动阳江东—恩平北油田群的重大发现；创新提出"拆离-变质核杂岩"型成盆机制，有望在开平南带形成亿吨级油田群。珠江口盆地逐渐形成古近系、古潜山、新洼陷等勘探新领域及多项技术系列，为南海东、西部油田持续增储上产提供了坚实的技术支撑，也打开了勘探新领域与新类型的勘探前景。资源评价结果显示，珠江口盆地富烃洼陷古近系及古潜山剩余资源量主要分布在惠州26洼、文昌A凹等，阳江—一统暗沙断裂带周缘及惠陆地区周缘新洼陷的原油资源最为丰富。

关键词: 富烃洼陷, 古近系, 古潜山, 新洼陷, 资源潜力, 珠江口盆地