Coal in the Upper Permian Longtan Fm in southern Poyang depression is called bark coal

because it is rich in periblinite. The bark coal generally contains over 40% of periblinite

as well as abundant hydrogen-rich components

such as degradinite or vitrinite B and microsporinites

etc. Simulated experiment of hydrocarbon generation shows that the oil-generating rate of bark coal is as high as 413.80 kg/t

so it is one of the best source rocks for coal-derived oil. Simulated experiment of single component hydrocarbon generation verifies that the periblinite is the most favorable component fro generation of liquid hydrocarbons

and is the major contributor to oil derived from bark coal. The level of thermal evolution of the Longtan Fm in southern Poyang depression is relatively low compared with the other source rocks in southern China. The superimposition of the Cretaceous basin would have created the geological conditions for secondary hydrocarbon generation of the source rocks and late reservoiring. Oil-source correlation shows that the oil in the reservoirs in Letan 1 well is typical coal-derived oil generated from the bark coal

indicating that the prospects for exploring coal-derived oil in Longtan Fm is good in areas with favorable preservation conditions in South China.