绥中36-1油田成藏条件及勘探开发关键技术

Accumulation conditions and key technologies for exploration and development of Suizhong 36-1 oilfield

绥中36-1油田是渤海湾陆相断陷湖盆中最大的古近系东营组油田,具有埋藏浅、规模大、层系单一、油品较稠等油藏特征。自1987年钻探发现以来,历经油藏评价阶段、产能建设阶段、综合调整阶段,截至2020年底,累计探明石油地质储量3.05×10^(8)t,累计生产原油9 000×10^(4)t,目前稳产350×10^(4)t/a以上。充足油源供给、优质储-盖组合、优势运移通道和良好保存条件是绥中36-1油田形成的关键地质条件,其中,邻近的极富烃辽中凹陷为绥中36-1油田提供充足的油源,东营组二段最大湖泛期沉积的泥岩与三角洲砂岩形成优质储-盖组合,NE向继承性发育的伸展-走滑大断裂控圈、封闭能力强,继承性鼻状构造与烃源岩大面积接触构成了油气向圈闭运聚的高速公路。针对海上首个大型整装稠油油藏形成的海上大型三角洲稠油试验区开发技术、海上稠油油田综合调整技术组合等系列实用性关键技术为绥中36-1油田的开发和产能建设提供了技术保障。

Suizhong 36-1 oilfield is the largest oilfield in the Paleogene Dongying Formation in the continental faulted Bohai Bay Basin, characterized by shallow burial, large scale, single layer series and heavy oil. Since the discovery of drilling in 1987, Suizhong 36-1 oilfiled has experienced the stages of oil reservoir evaluation, productivity construction and comprehensive adjustment. By the end of 2020, the cumulative proved geological reserves reached 3.05×10^(8)t and the cumulative production of crude oil amounted to 9 000×10^(4)t. At present, the stable yield is above 350×10^(4)t/a. Adequate oil source supply, high quality reservoir-cap combination, favorable migration pathway and good preservation conditions are the key geological conditions for the formation of Suizhong 36-1 oilfiled. Specifically, the adjacent Liaozhong sag with extremely rich hydrocarbon resources provides sufficient oil source for Suizhong 36-1 oilfiled, a high quality reservoir-cap combination is formed by mudstone and delta sandstone deposited in the largest lake flooding period in the second member of Dongying Formation, the extensional strike-slip fault with inherited development in NE direction has strong trap-controlling and sealing ability, and a large-area contact between the inherited nose structure and source rock form a highway for hydrocarbon migration to traps. Additionally, a series of practical key technologies, such as the development technology of the first offshore large-scale delta heavy oil test area formed by large integrated heavy oil reservoirs, and the comprehensive adjustment technologies combination of offshore heavy oil fields, provide technical support for the development and productivity construction of Suizhong 36-1 oilfiled.