AnoilflowobtainedfromtheMiddleOrdovicianFengfengFormationcarbonatereservoirinthewellKG-3,Kongxiburial-hillzonein1993markedabreakthroughinpetroleumexplorationofthehigh-matureLowerPalaeozoicstrata,NorthChina.BoththeLowermemberoftheFengfengFormationandtheSecondMemberoftheUpperMajiagouFormationintheMiddleOrdovicianaresupposedtobethemainsourcebeds.Oilgenerationpeaksrangefrom1.0%to1.6%inRo,showinga搇ageffect?ofoilgenerationinhigh-maturecarbonatesourcerocksundermulticyclictectonicmovementconditions.TheKongxiburial-hillzoneadjoinsapotentialOrdoviciansourcekitchen.TheKG-3Ordovicianburial-hillreservoirhasundergonetwooilfillingevents,i.e.,anearlyeventintheLateCarboniferous-PermianandamoresignificantlateeventintheearlyEogene.
