Shallow Gas Accumulation Discipline in Heidimiao Layers of Daqing Changyuan in Northern Songliao Basin

5th Annual International Workshop on Materials Science and Engineering

Sun, Hailei^1

Exploration and Development Research Institute, Daqing Oilfield Company Limited, Daqing

163712, China^1

关键词: Accumulation model;    Formation mechanism;    Gas exploitation;    Heavy hydrocarbons;    Horizontal distribution;    Hydrocarbon source rocks;    Reservoir fractures;    Sedimentary environment;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/585/1/012064/pdf
DOI  :  10.1088/1757-899X/585/1/012064

来源: IOP

【 摘 要 】

Shallow gas has been a hotspot in present natural gas exploitation and development due to its shallow depth, low cost of exploitation and development, high production and good benefits. Combined data of core, log, 3D seismic and indoor analysis experiments have been studied. Results indicated: In northern region of Daqing Changyuan, shallow gas can be defined as oil type associated gas from underlying reservoir while in the southern region as mainly degradation gas of crude oil mixed with oil type gas of heavy hydrocarbon component from bacteria degradation in early stage. Main accumulation-affected factors of shallow gas in Daqing Changyuan contain: (1) accumulation of shallow gas was based on early large reservoir as source of gas, which was formed by supply of many high-quality hydrocarbon source rocks; (2) many reservoir cap combinations in prograded delta front sedimentary environment controlled accumulation location; (3) quaternary structural trap related with source reservoir fracture controlled horizontal distribution of shallow gasaccumulation. Gas reservoir was defined as structural gas reservoir.Consequently, for degradation gas reservoir and associated gas reservoir of southern and northern Daqing Changyuan respectively, formation mechanism and accumulation model have been founded.