Lanliao fault belt on the east margin of Puyang Depression is a tensile fault belt formed in Yenshan Epoch.The belt
being 140 km long and 6-8 km wide
is situated close to a deep-depressed oil-generating belt in the west and the Luxi Uplift in the east.Most of the Mesozoic and Upper Paleozoic are absent in its upper wall
but sediments of various geological times are well preserved on its foot wall.The 3rd member of the Neogene Sha-hejie Formation is the main source rock.Along the fault belt
a lot of nose structures and subaqueous fans developed on the footwall
and buried-hills and bioherms on the upperwall.Hydrocarbon could be found on both walls.The main types of hydrocarbon traps in the study area are faulted-nose structure formed by basement uplift of the footwall
fault-nose resulted from the slope of slumping conglomerate on steep slope