Relationship between tertiary volcanic rocks and hydrocarbons in the Liaohe basin, People's Republic of China

The Liaohe basin is a Tertiary rift developed on a paleohigh, characterized by widespread volcanic rocks and active fault subsidence. Source rocks con sist of mudstone of Paleogene age, and reservoir rocks consist of volcanic rocks, sandstones of Tertiary age, and buried hills of Mesozoic-Paleozoic a ge. Traps are a combination of structural and stratigraphic, with drape fea tures being dominant. Cap or seal rocks consist of volcanic rocks and mudst ones of Paleogene age. Source maturation and migration timing are closely l inked to the volcanic episodes. The higher geothermal gradient provided by magmatic activity resulted in early maturation of source rocks. These hydro carbons are locally reservoired in volcanic rocks. These favorable hydrocar bon-play parameters make the Liaohe basin an attractive hydrocarbon provinc e.