DISCUSSION ON THE HYDROCARBON SOURCE ROCK CHARACTERS OF THE LIULAOBEI FORMATION ON THE FRINGES OF THE HEFEI BASIN

Based on the data of outcrops and wells on the fringes of the Hefei Basin and the synthetical analyses of stratigraphic characters, organic geochemical indexes and lithofacies paleogeography, the authors believed that the organic abundance of the Liulaobei Formation reached the standard of hydrocarbon source rocks. Its matrix type was Ⅰ-type kerogen, it mudstone was thick, its hydrocarbon percent conversion was high, and its hydrocarbon productive amount was great. Though the organic material of the Liulaobei Formation was overmature, it can still split into condensate oil and humid gas. So, it was suggested that the Liulaobei Formation can be considered as the gas source rock of the Hefei Basin. Besides, based on the stratigraphic and geophysical data, it was inferred that the Liulaobei Formation was existing in the inner of the Hefei Basin. These conclusions provided theoretical bases for exploring gas pools in the Hefei Basin.