Structural And Sedimentary Characteri-stics In Gao Ⅲ Of Gaotaizi Reservoir In Xingbei Development Area Of Daqing Oilfield

More and more oil and gas were found during well testing in GⅢ of gaotaizi reservoir of xingbei development zone of daqing oilfield. But reservoir belongs to external delta front micro facies, reservoir is small, fragmented, low abundance of reserves and the complex oil-water distribution. So in this paper, directed by structural geology, taking full advantage of the core, drilling, logging and high resolution seismic data, based on the integrated technology of wavelet optimization, synthetic seismogram calibration, spatial variable velocity imaging.3D integrative interpretation of horizons and faults are achieved, identification method of small faults is explored with the guidance of well fault-point data through coherence cube and three-dimensional visualization technology. Two structural maps of GⅢ group reservoir are made,93traps are identified. The research of structure development and growth index of faults shows that in xinbei the periods of fault activity can be divided into qingshankou, from yaojia to the first and two stages of nenjiang and the three and four stages of nenjiang, and shows that in xingbei three fault systems were developed and fracture has good inherit with Fuyu reservoir.In the mean time, GⅢ group reservoir has been divided into one long term dropping semi-cycle, three middle-term cycle and six short term cycle by using the method of fine stratigraphic classification and correlation, the stratigraphic framework of GⅢ group, gaotaizi reservoir in xingbei development zone has been established. The microfacies of the studied area are divided into such six types:subaqueous distributary channel; inner distal bar; outer distal bar; sheet sand; inter-sand sheet shale and front delta mud microfacies.Furthefmore, through lithology interpretation and electrical analysis, I also establish their logging facies model. Controlled by the microfacies of single wells, combined with seismic reflection bedding slices and beitang sag, the boundary of sedimentary microfacies is determined.8sedimentary time units’plane sedimentary microfacies maps of GⅢ group, gaotaizi reservoir, xingbei development zone are confirmed, precise identify the characters of reservoir distribution. Fine structure explanation for whole region is implemented These results provide solid geologic basis for the favorable exploration area prediction and the assessment of exploitation potential.