缅甸D区块石油地质特征及勘探潜力

Petroleum geologic characteristis and exploration potential of  Block D in Burma

李红 曹永斌 王新云

摘要：缅甸D区块位于伊洛瓦底盆地中西部，主要勘探层系始新统发育东、西两大三角洲沉积体系，沉积相以三角洲平原〖KG-*4〗-前三角洲亚相以及浅海相为主，构造演化主要经历了始新世的统一沉降期、渐新世—中新世的差异沉降期和上新世以后的逆冲推覆期3个阶段，形成了南北走向、东西分带的“四隆二凹一斜坡” 的构造格局。烃源岩以塔本组的灰色泥岩和煤系泥岩以及朗欣组的暗色泥岩为主，有机质丰度高，具有非常好的生烃能力。蓬当组、塔本组和提林组3套储〖KG-*4〗-盖组合保证了区域油气的有效聚集和保存。圈闭类型有断层控制的背斜圈闭和砂岩透镜体圈闭两种。烃源岩热演化研究表明，区域生烃时间、运移方向、储盖组合、圈闭形成等成藏条件配置关系合理，D区块油气有利富集区主要集中在3个构造带上，分别是Patolon背斜带、Mahudaung背斜带和Thingadon复向斜带。

Abstract: Block D located in the westerncentral of Irrawaddy basin in Burma, has two major Eocene deltaic sedimentary systems with one in the east and the other in the west. The main sedimentary facies include delta plainprodelta and shallow marine facies. Block D experienced three main tectonic evolution phases including the Eocene united subsidence, the OligoceneMiocene differential subsidence and the postPliocene overthrusting. The tectonic framework of Block D is characterized by NStrending and EWzoning “four uplifts, two depressions and one slope”. The quality source rocks in Block D are dominated by the Tabyin Formation gray mudstone and coalseam mudstone, and the Laungshe Formation dark shale. They feature in high organic abundance and high hydrocarbongeneration potential. Moreover, three reservoirseal combinations in the Pengdang, Kabaw and Tabyin formations provide favorable conditions for effective hydrocarbon accumulation and preservation. 〖JP+1〗There are two trap styles in Block D, including anticline trap controlled by faults and sand lens trap. Study〖JP〗 of thermal evolution of source rocks indicates that the timing of hydrocarbon generation, migration, trap formation and reservoirseal combination is rational. The potential plays of Block D mainly occur in three structural belts including Patolon anticline belt, Mahudaung anticline belt and Thingadon synclinorial belt.

10.11743/ogg20110215