Research On The Volcanic Accumulation Of Changshen 5^th Well Area In South Songliao Basin

Under theory of volcanic rock petrology,petroleum geology Combined with gas exploration practice of southern Songliao basin,a comprehensive evaluation on the the volcanic lithology,volcanic facies,reservoir space,reservoir property,reservoir formation of well changshen 5 th have been made based on the available drilling well logging,mud logging,sidewall coring information and a series of studies such as observation of core section, log evaluation, source rock evaluation.The result shows that with the good organic matter type,high organic abundance, and favorable maturity—mature to high mature ,yingcheng formation are high quality source rocks.Oil generation threshold depth of changshen 5 th area is 1700m。Hydrocarbon generation history suggests that the main hydrocarbon generation periods of yingcheng and shahezi formation is 115Ma-90Ma and 130-100Ma respectively. Reservoir evaluation suggests that physical properties of Yingcheng section are not good for the reason that main porosity is less than 4%, permeability is low,stoneley wave fluidity index are mainly 1-6us/ft。Reservoir forming conditions and controlling factors analysis indicate that the key factor controlling petroleum accumulation in target area is fracture.