Permian Hydrodynamic Field Division And Prediction Of Tight Oil Prospecting Areas In Junggar Basin

Based on geological outcrop,core,well logging,seismic and analysis test data,detailed studies of tight reservoirs in Fengcheng Formation,Fengcheng area and Lucaogou Formation,Jimsar sag was performed,focusing on tight oil distribution,tight reservoir characteristic,effective source rocks,strata pressure,physical property of crude oil and tight oil reservoirs type.The lower boundary of buoyancy-controlled accumulation is determined by adopting reservoir examples,physical property statistic analysis and physical simulation experiment,while the bottom boundary of hydrocarbon accumulation is also determined by adopting irreducible water saturation,minimum flow pore throat radius and potential difference inside and outside reservoir,which is verified by the actual exploration results.Based on the above research,main controlling factors of tight oil reservoir indicate that:(1)the hydrocarbon generating intensit y controls the critical distribution range of tight oil,the larger the hydrocarbon generation intensity the more the oil content;(2)lithology,physical property and favorable reservoir thickness are the three controlling factors of oil~bearing features in tight reservoir of study area;(3)force balance boundary controls the accumulation threshold of tight oil;(4)stable structural environment provides a basic condition for tight oil accumulation.Combined with the division of Permian hydrodynamic field,establish a limited hydrodynamic field controlling the tight oil distribution model,then predict the favorable tight oil prospecting area in Junggar Basin,which can provide a theoretical basis for the tight oil exploration and development in the whole Junggar Basin.