Geological and geochemical data of 13634 source rock samples from 1286 exploration wells in six representative petroliferous basins are examined to study their Active Source Rock Depth Limits (ASDL). Active source rocks and the discovered 21.6 billion tons of reserves in six representative basins in China and 52926 oil and gas reservoirs in the 1186 basins over the world are found to be distributed above the ASDL, illustrating the universality of such kind of depth limit.