The Clastic Reservoir Characteristics Of Cretaceous In SDQ Work Area

In this thesis, we used Sandaoqiao depression’s contiguous3D post-stack time migration seismic data, guided by Drilling, well logging, seismic, laboratory analysis and production of dynamic data, to carry out sequence stratigraphic division. Under the control of sequence stratigraphic, we carry out the fine structure interpretation, reservoir prediction, sand distribution and reservoir quality evaluation. By means of analyzing oil and gas forming conditions and factors of the main exploration, we can establish the hydrocarbon accumulation model of study area and found out lots of favorable targets for comprehensive evaluation.3-D seismic research area of the SDQ structural position is Kuqa Depression, Tarim Basin northeast depression area and Shaya uplift binding site, gently fold in the south of Kuqa depression with the southwest corner, and the western of Shaya uplift the Yakela fault block. The3-D seismic coverage research area is531.4km2in the2000years. The presence of the technical difficulties:First of all, the geological and seismic conditions of research work are complex. Secondly strong heterogeneity of the Mesozoic and Cenozoic clastic reservoirs in sedimentary reservoir characteristics is not clear. Finally the reservoir characteristics are relatively weak. These reasons result in the implementation of the goals of the Mesozoic-Cenozoic traps and Evaluation difficult. Moreover, the impact of the quality of seismic data, the implementation of the clastic trap is difficult, especially for lithology stratigraphic traps looking still at the exploratory stage.According to the current work area difficulties, the following technical means are used for research. Through the sedimentary facies study, reservoir characteristics and trap the implementation of the three aspects of the research work, deepen understanding on the Yakela fault block in the western part of the Mesozoic-Cenozoic trap condition, improve the accuracy of the implementation of the clastic trap, in particular to strengthen the lithology the stratigraphic traps implementation to reduce the risk of exploration and development, and to lay the foundation for the next step exploration and development. The paper is relying on "the Yakela fault block in the western part of the Mesozoic-Cenozoic favorable target evaluation". First of all, the use of horizontal slices, coherent body technology, spectral decomposition techniques, edge detection and others can identify complex faults for fine structural. Make full use of existing wells to produce synthetic, we can establish an accurate velocity model used for depth conversion. Layer flattening technology is used for studying the tectonic evolution history of the work area. Then, seismic attributes, various attribute information of the target layer is extracted to identify the favorable sedimentary facies and reservoir. Then, Well data and stratigraphic model used as constraints. Sparse spike inversion method generates the absolute acoustic impedance data and identifies favorable reservoir by Sand body fluoroscopy. For the fault of area develops and sedimentation changes rapidly, we will use EarthModel FT module of Jason software to establish three-dimensional structure model and carry out high-resolution inversion.Based on these studies above, we summarized the favorable reservoir conditions of forming reservoir:Firstly, sufficient oil source is the material basis. Secondly, good reservoir and reservoir conditions are important conditions. Thirdly, the construction site and favorable reservoir configuration is the key. Fourthly, regional cap rock is needed to form good storage conditions. Fifthly, good combination of source、reservoir and cap is favorable factors. Lastly, Valley slope break zone control sequence LST and HST sand body lithologic reservoirs in a favorable position in the distribution.Based on these studies above, we summarized the following understanding: Firstly, from the drilling, logging data, the Cretaceous Baxigai Formation lithology contain brown-red, green, gray, gray-fine-grained, fine-grained sandstone. The components are mainly of sandstone lithic sandstone, and less of quartz sandstone. Pore Types of reservoir are primary intergranular porosity and a small amount of dissolution pores. Baxigai group, the average porosity of about10%and permeability differences, the maximum penetration rate of372, while the minimum permeability of only0.04; the reservoir is strong heterogeneity. Secondly, for small faults in the work area, the use of seismic coherence analysis can be a better solution to the fault plane mix and profile interpretation. Small faults interpretation is more useful to study fault-controlled low-amplitude structure. Lastly, Sandaoqiao seismic data due to the low frequency of the target layer seismic conventional constrained inversion is difficult to obtain good results. This study to improve the resolution method for inversion:first post-stack seismic data by Billiton frequency processing to improve the resolution of seismic data; Then there are the high-resolution wavelet extraction with wavelet well constrained inversion model-based method to improve the resolution of the seismic inversion; Finally, using a variety of inversion methods were compared, the purpose of thin reservoir identification method.