The Study Of Sedimentary Microfacies And Reservoir Evaluation Of Upper Jurassic In Smarker Area Of Amu-Darya Basin

Smaker area is located in the northeast region of the Amu Darya Basin. According to the exploration, the Upper Jurassic carbonate reef reservoir of the Amu Darya Basin has wide oil and gas potential, but the geology research is relatively weak. In this paper, on the basis of previous research results, it will use the sedimentology, reservoir geology, geophysics, and other theories, combined with the dill core, logging, seismic and related geological data, to study the detailed stratigraphic correlation, sedimentary facies and reservoir characteristics of the Upper Jurassic, classify and evaluate the reservoir, and point out the high quality reservoir of this area eventually, in order to provide the basis for further exploration and development.On the basis of the detailed analysis about group lithology and electric characteristics in the Upper Jurassic Karloff - Oxford, referring to previous research results, making full use of three-dimensional seismic data, stratigraphic principles and methods of application, here divide the Karloff - Oxford bottom-up into 8 lithologic groups to establish the stratigraphic framework in this area, and analysis the characteristics of each stratigraphic section finely.Whereas the research of the core description, thin section analysis, logging features, seismic data and regional analysis of sedimentary background, we mention that the Karloff - Oxford group develops carbonate platform, platform margin, front slope facies types, and can be divided into 7 sub-facies and 13 microfacies. Then through analyzing the single well facies, profile facies and the distribution of seismic characteristics, we define the distribution of the sedimentary characteristics of facies and evolution history of the Karloff - Oxford group, and establish the sedimentary facies mode of the area.Using the information of cast thin sections, scanning electron microscopy, physical property, mercury penetration and other data, to do the research of reservoir rock characteristics, reservoir space type, porosity and permeability characteristics, pore structure characteristics. It suspects that the primary reservior rock are reef limestone and limestone particles, the main pore space type is corrosion, followed by cracks and caves, physical property is good , the porosity and permeability are moderate, and the pore structure is moderate pore throat. Then the passage analyzes the controlling factors of reservoir development. Referring to the general characteristics of sedimentary facies, reservoir characteristics and the lower limit of effective reservoir properties, we do the classification and evaluation of the Karloff - Oxford group reservoir. The reservoir is divided into three categories, the mainly ones areâ…¡andâ…¢, the best one is in XVm section, XVp is the middle section, and XVac section is poor. The eastern reef platform of Michael McNair anticline is mainlyâ… andâ…¡reservoir, which are large scale, good physical properties, and with good exploration potential.