The Method Of Characterizing Reservoir Heterogeneity By Integrating Well-to-Seismic And Its Application In The Second And Third Kinds Of Blocks In Chaoyanggou Oilfield

For the high water cut development stage of old oilfields, remaining oil prediction is the core problemto ensure a stable oil production and improve production yield. Influenced by tectonic and reservoirheterogeneity, remaining oil distribution is highly scattering and local enrichment. The key to optimize wellnet injection-production relationship and remaining oil tapping is increase the precision of reservoirheterogeneity cognition by integrating various devices to characterize faults, micro-amplitude structure andthe distribution of sand bodies between wells. Second and third kinds of blocks in Chaoyanggou Oilfieldhave typically low porosity and permeability, high dense fracture, well breakpoints combined rate is onlyreach80%, small scale and quickly changed sand body. Logging methods cannot only describe distributioncharacteristics of sand body, so renewed reservoir heterogeneity characterization by integrate logs andseismic data is needed.In this thesis, based on the main study area, which is second and third kinds of blocks in ChaoyanggouOilfield, the study of reservoir heterogeneity characterization of seismic and logging was carried out. Onthe foundation of standardized logging data, calibrated geology horizon by logs and seismic, then finehorizon interpretation, small faults and micro-amplitude structure characterized by various methods, gradedcharacterization of different scale channel sand bodies and the3D fine geologic modeling technologieswere used to determined spatial distributions of micro-structures between wells and fractures. Predicted thedistribution of sand bodies between wells and the characteristics of porosity, permeability and saturationreasonably and accurately, then we made the fine geologic research process for second and third blocks inChaoyanggou Oilfield which can effectively guide the adjustment in development, increase the designwells’density.The main achievements and innovations are as follows:(1) Standardized acoustic curves by the methodcalled “double standard layer”, reconstructed density curve and improved the integration of well andseismic data calibration’s quality in three steps by the amount of fine-tuning through fine syntheticseismogram. Aiming at the difficulties in seismic reflect stability of fluvial facies, large scale finelyinterpreted standard layers by flattening and frequency band filtering section. Realized the fineinterpretation of sedimentary units’ interface by trend-surface interpolation method based on standardlayers’ control;(2) Based on the explain idea “Guided by the well breakpoint, assisted by multiple attributefusion slices”, profile located by well breakpoints, plane oriented by attribute fusion slices, finely interpreted by continual arbitrary lines and spatial closured by3D visualization, so that we can fulfilled thegoals of small fault characterizations gradually from point-line-plane. We can effectively identify the smallfaults which displacement less than5m and the breakpoint combined rate is more than90%;(3) Under theguidance of well layered and controlled by top and bottom interface of sandstone group finely interpretedby seismic, we located the micro-structure morphology between wells by the space variable speed mappingtechnology, which controlled structure error within2‰;(4) The method which combined the forward andinversion discussed the seismic attributes analysis and inversion method’s vertical and lateral resolution fordifferent scale of sand body, providing the basis for the characterization of different scale of channel sandbody by integration of logs and seismic. We predicted the sand stone by the seismic inversion andparameter optimization, combined the best sparse pulse wave impedance with geostatistical stochasticinversion, improving the accuracy and reliability of reservoir prediction. Tested by the new drilling andposterior wells, prediction rate of channel sand bodies whose thickness are more than3m reaches above80%;(5)“Controlled by well points’ micro-facies and guided seismic attributes’ tendency” was used tocharacterize the continuity, extending length and direction of small channels.“Integrated the thickness andslice of inversion sand body” was used to characterize the width, morphology and combination of largechannels.“Combination of seismic recognition marks and attribute slice” was used to characterize thesingle channel boundary among compound sand body. Integration of logs and seismic perfectedmicro-facies of44sedimentary units in the south of Chao44Block and improved the cognizance’saccuracy of the channel sand body distribution’s characteristics;(6) Based on the characterization ofstructure and sand body heterogeneity by logs and seismic, we used the technology on the basis ofstochastic modeling controlled by facies to realized the heterogeneity description of porosity, permeabilityand saturation properties;(7) The outcomes of characterization of faults, micro-amplitude structure,channel sand body and the reservoirs’ physical parameters by combination of wells and seismic, whicheffectively guided the tapping of remaining oil, accomplished the design of well net injection-productionrelationship and infill wells for second and third typical blocks, provided technical support for the old oilfields’fine tapping.