摘要
珠江口盆地珠一坳陷古近系石油资源丰富,其中的陆丰地区属于富烃凹陷。古近系石油主要蕴藏在文昌组砂岩的多种类型孔隙中,成岩作用特征决定了砂岩中发育的主要孔隙类型。以储层薄片显微定量分析为基础,结合扫描电镜、阴极发光、电子探针等分析,明确了古近系文昌组砂岩的成岩作用特征,获得了储层的各类孔隙组成及其含量分布,并进一步探索了储层主要孔隙的发育成因。文昌组砂岩主要发育颗粒溶蚀孔,其次是残余原生孔和胶结物溶孔。颗粒溶孔主要是由泥岩演化释放出的有机酸对长石溶蚀而成,其次是大气淡水造成的溶蚀;胶结物溶孔主要是由早期断裂、裂缝沟通大气淡水引起的碳酸盐胶结物的溶蚀而形成;残余原生孔的发育除与砂岩成分、结构成熟度相关度较高之外,还与地层抬升、早期压实破坏和早期油气充注形成的异常压力密切相关。研究结果表明,邻近生烃凹陷的古斜坡、古隆起及其早期断裂发育的高能相沉积砂岩是陆丰地区文昌组砂岩孔隙发育的关键。研究结果对文昌组深埋藏砂岩的储层预测具有重要意义。
There is abundant hydrocarbon resource in the Paleogene strata of Zhuyi Depression in Pearl River Mouth Basin, and the Lufeng is considered as a hydrocarbon -rich depression. The Paleogene oil mainly accumulates in the various types of sandstone pores in the Wenchang Formation. The major pore types in the sandstone is greatly dependent on the diagenesis. Based on the quantitative microscopic analysis of reservoir thin-sections, the Paleogene sandstone diagenesis patterns of Wenchang Formation were determined by combining with scanning electron microscopy, cathodoluminescence, electron probe analysis and other data. The pore classification and contents were gained to further explore the genesis of reservoir major pore types. The sandstone in the Wenchang Formation mainly contains particle dissolution pore, followed by residual primary pore and cement dissolution pore. The particle pore mainly results from the organic acid released by mudstone evolution to dissolve the feldspar, followed by the dissolution caused by atmospheric fresh water. The cement dissolution pore was mainly created by the carbonate cement erosion results from the atmospheric fresh water connected by early fault and fracture. The residual primary pore is not only highly correlated with sandstone composition and structure maturity, but also closely related to the abnormal formation pressure results from stratum uplifting, early compaction damage and early hydrocarbon changing. Re-search indicates that the paleoslope, palaeohigh and sedimentary sandstone with high-energy facies that are adjacent to the hydrocarbon generation depressions are considered as the major factors for the sandstone pore development of Wenchang Formation in Lufeng. This research could provide certain significance for the deep buried sandstone reservoir prediction in the Wenchang Formation.
作者
吕正祥
文艺
赵福
曹勤明
张琴
Lyu Zhengxiang;Wen Yi;Zhao Fu;Cao Qinming;Zhang Qin(Chengdu University of Technology y Chengdu, Sichuan 610059, China;Slate Key Laboratory of Oil and Gas Reservoir Geology and, Exploitation (Southwest Petroleum University), Chengdu, Sichuan 610059, China;CNOOC Shenzhen Branch, Shenzhen, Guangdong 518067, China)
出处
《特种油气藏》
CAS
CSCD
北大核心
2019年第3期18-23,共6页
Special Oil & Gas Reservoirs
基金
“十三五”国家科技重大专项“南海东部海域勘探新领域及关键技术”(2016ZX05024-004)
