Reservoir Property Controling Factors And Classification Of Triassic Baikouquan Formation Of West Slope In Mahu Sag,Junggar Basin

Exploration practice indicates that the Triassic Baikouquan Formation in the slope zone of Mahu depression of Junggar Basin is characterized as fan-controlled large-area accumulation and becomes a new base to increase oil and gas reserves and production for Xinjiang oilfield.but glutenite reservoir property controling factors is not clear and the evaluation of reservoir is difficult.This study use the ideas of reservoir geology and well logging geology,through the comprehensive research of a large number of core data,analysis and testing data,well logging and mud logging data,The study conducts the following work:the analysis lithology and lithofacies,the research of the control factors of reservoir property and reservoir classification,the standard of classification of Mahu sag coarse clastic particle size were established according to 61 key wells cores were observed in the study area and,according to the characters of lithological facies,glutenite reservoir property control factors and influence mechanism are clear,establish the classification criteria of glutenite,clear the influence of diagenesis on reservoir physical property.Research has made the following conclusion:(1)according to statistics of 23 wells 1635 lithologic sample,the porosity > 7% accounted for more than 70% in the study area reservoir lithology is mainly for fine conglomerate,sandstone and conglomerate,fine breccia in small advantage.(2)the study find the control factors of low porosity,low permeability reservoir is mainly clay content,granularity separation and diagenesis.Clay content is the most important factors of reservoir physical property,the change of porosity and permeability a linear relationship with Clay content;Moderate granularity is the key to form high quality reservoirs,the physical property of fine conglomerate and sandstone is best;Secondary dissolution on reservoir can obviously change physical property.(3)the study combine reservoir discovered in the west slope area with the logging response of reservoir physical parameters,establishing the classification of glutenite reservoir evaluation method and standard of porosity and permeability,according to microscopic petrology and productivity prediction,a successive classificate evaluation standard for the quantitative characterization are established.