摘要
吉木萨尔致密油层具有致密、特低渗、层厚、砂泥岩薄互层发育等特点,由于储集层条件、改造工艺等多重限制,常规压裂工艺改造难以实现该类油藏的商业开采。分析了致密油藏地质特征与改造难点,借鉴国外致密油藏成功开发经验,针对储集层物性极差无自然产能等特点,提出"大型压裂"与"体积压裂"复合改造新理念,兼顾形成复杂缝与高导流主力长缝,扩大改造体积,提高单井产量。2012年,在吉木萨尔凹陷致密油层,探索了水平井分段压裂和直井分层压裂两种改造模式,优选及配套了系列工具、工艺及技术,实现了改造理念。现场累计改造6井35层,均获工业油流,其中水平井分15级压裂,压后产量达71.79 m3/d,是直井分层压后产量的7倍左右,成为准噶尔盆地致密油藏勘探实现重大突破的标志,同时也为致密油藏后期大规模开发积累了重要经验。
The dense oil reservoir in Jimusaer sag is characterized by compact, ultra-low permeability, thick, thin sand-shale interbed, etc. Owing to many restrictions of the reservoir condition and modification process, etc., using the conventional fracturing modification is diffi- cult to realize the commercial exploitation of such a reservoir. This paper investigates the geological characteristics of the reservoir and its difficuhy for modification, introduces the successful experiences for development of dense reservoirs abroad, and proposes a new idea of composite modification of ＂large-scale fracturing plus volume fracturing＂ for the reservoir with very poor petrophysical property and with- out natural productivity by depletion drive, comprehensively taking account of complex fractures and high flow-conductive major long frac- ture in order to enlarge fracturing volume and improve single well production. For this purpose, two approaches of horizontal well segment fracturing and vertical layered fracturing in the dense oil reservoir in Jimusaer sag were performed, and a series of tools, techniques and technologies were optimized and equipped in 2012, with the cumulative modification of 6 wells and 35 layers in the field, from which the commercial oil flows were obtained. The horizontal well＇ s fracturing was performed by 15 levels, the production after fracturing reached 71.79 m3/d, amounting to about 7 times that of vertical wells by layered fracturing approach. These successful pilot tests have become marks of major breakthrough for exploration of the dense oil reservoir in Junggar basin, meanwhile, provided significant experiences for late large-scale development of such reservoirs.
出处
《新疆石油地质》
CAS
CSCD
北大核心
2013年第6期710-712,共3页
Xinjiang Petroleum Geology
关键词
吉木萨尔凹陷
致密油藏
体积改造
分层压裂
分段压裂
Jimusaer sag
dense reservoir
volume modification
layered fracturing
segment fracturing
