The Study On Sedimentary Microfacies Of Middler Submember Of Es3 In The Pan 40 Block Of Linpan Area

The Pan 40 Block of LinPan area is located in the central plateau of Huimin Depression with Linyi footwall.South of Linnan sag.It contains many oil layers along its vertical direction.And the Middler Member of Es3 is the main oil-bearing reservoir.Since the development,it has long been in the low-yield state due to the limitation of its complexed geological conditions.Taking the LinPan area as the research area,this paper will focus on establishing an accurate stratigraphic framework and doing a sedimentary microfacies study by using sequence stratigraphy,sedimentology and the underground geology.A conclusion of various subfacies and microfacies identifiers can be expected.Finally,a sedimentary facies mold will be built accordingly.The time-frequency diagram obtained by "wavelet transform" combined with the results of the Fourier transform of the well seismic is used to determine the Middler Member of Es3 based on the drilling,well logging,seismic data.The model is established with the wavelet coefficients of different scales are obtained by using wavelet transform and datum.The research area is divided into two sandstone bodies.The two sand group is further divided into seven sub layers by adopting the cycle-thickness contrast method and equal-height time unit contrast method.A conclusion of various identifiers of subfacies and microfacies is made through observing the core,as well as analyzing the sedimentary facies and the characteristics of the logging curve.The sedimentary subfacies of the delta front from the mainly developed shallow lake facies of the Es3 submemer of Linyi footwall is identified.And it can also be subdivided into five major microfacies,including subaqueous distributary channel,underwater natural levee,mouth bar,front sheet sandand.Middler submember of Es3 in the Linyi hanging wall developed turbidite fan and lake including middle fan,outer fan and semi-deep to deep lake,which can be divided to channel,interchannel,channel lateral margin,outer fan mud,creeping turbidite sandbodies and semi-deep lake to deep lake mud microfacies.A detailed summery of the characteristics of various sedimentary micro facies is provided.Using single well phase and mineral facies section as the basis,the paper analyzes the features of the small sand body and sedimentary facies flat sedimentary microfacies distribution based on the contour map drew on the basis of the sand thickness,shale content,Space permeability and logging curve property.The two lower sub layers of two sand group are front sheet sand.Subaqueous distributary channel and mouth bar present in the two upper sub layers of one sand.The size of the underwater distributary channel and mouth bar in the one sand group from below to below are reduced in turn.A sedimentary facies model is established according to the provenance condition and the features and the evolving trend of sedimentary microfacies distribution.