Abstract:The oil and gas exploration of Erlian Basin began in 1955, and now more than 10 oilfields have been found, such as Zhabu oilfield, Jigesen oilfield. But, difficulties exist in the exploration of Erlian Basin, due to, for example, the complex of deposit geology and the low level of proven deposits. The previous studies show that there are 50 sags with an independent sedimentary unit of their own, and with their own similar characteristics of hydrocarbon generation, migration and accumulation. But as a matter of fact, even in different subsags of the same sag, the distribution of hydrocarbon source rock and geochemistry characteristics of hydrocarbon source rock are different. This paper analyzes the data of more than 20 sags in Erlian Basin and the Lower Cretaceous hydrocarbon source rocks of more than 30 wells. And then, some common features of distribution and the geochemical characteristics of hydrocarbon source rocks are revealed, and their differences and the effects on the distribution of oil and gas are compared. It is shown that the geochemical characteristics of Lower Cretaceous source rocks have a great influence on the production and distribution of oil and gas in Erlian Basin. Therefore, for the sags with thick dark mudstone, the abundance of organic matter is basically above the medium, the organic matter type is more partial sapropel (type I or II1), and the dark mudstone is buried deeper than its oil generation threshold depth, and is more conducive to oil and gas output. The contribution of the source rocks of Aershan group to the reservoir is bigger than that of Tenggeer group, so the source rocks of Aershan group have a bigger influence on the distribution of oil and gas.
陈治军, 高怡文, 李科社, 贺永红, 刘护创, 于珺. 二连盆地下白垩统烃源岩特征及其对油气分布的影响[J]. 科技导报, 2014, 32(32): 46-53.
CHEN Zhijun, GAO Yiwen, LI Keshe, HE Yonghong, LIU Huchuang, YU Jun. Characteristics of Lower Cretaceous Source Rock and Its Effects on Hydrocarbon Distribution in Erlian Basin. Science & Technology Review, 2014, 32(32): 46-53.