Technique And Application Of Seismic Reservoir Prediction Of Marine Facies Carbonate

The carbonate reservoir is the most important domain of the exploartaion and production of oil and gas in the world, which occupies approximately a half of the reserves and output of the globe. Exploration and reserches in the past years shows that marine facies carbonate reservoir developed in Cambrian-Ordovician system of Lower Palezoic in Tarim basin are distributed over large areas and have a wide range of structural, and have adequate source of oil and gas and with the excellent base of oil geology, which are the most important series of strata of the reservoir exploration in platform-basin region of Tarim basin and have a huge potential of exploration. Tazhong area is one of the important areas of reservoir exploration of marine facies carbonate of Tarim basin. Reserovoir of reef-shoal facies in Lianglitage formation of upper Ordovician series is found in well Shun2 and well Shun6 in the west of Katake uplift in Shunxi area, which have good show of oil and gas; Industrial gas flow have been obtained in well Zhong1 in Yingshan formation of lower Ordovician series and well Gulong2 in Yijianfang formation of middle Ordovician series, all this show a wide exploration prospect in non-main part of No.1 slope break belt of Tazhong area, but recently the extent of reservoir exploration and research are not nearly enough, the comprehensive research aiming at it is benefit for widening the thinkway of reservoir exploration in Tazhong area and has important realistic meaning.Based on the theories of reservoir geology of carbonate reservoir and geophyics, the paper describes in detail the physicality, pore structure, typed of reservoir space and geophysical characters of carbonate reservoir of Ordovician series in non-main part structure area of No.1 slope break belt in Tazhong area through the drilled wells in the work areas, and analysises systematically the main controlling factors of development of carbonate reservoir, and points out the multiformity of carbonate reservoir in research areas, which are divided into reef-shoal type and karst type on the macroscopical level, while fissure-pore type, fissure-hole type and cave type on the microscopic level. The reservoir in this area has the characters of low porosity and permeability, large transversal change and strong heterogeneity. Sedimentary facies zones, diagenesis and tectonism are the main controlling factors of reservoir development.In Tazhong area of Traim basin(Shunxi, Ka1, Gucheng are the main research areas), reef-shoal reservoir in the upper Ordoviaian Lianglitage formation and karst reservoir in the lower Ordoviaian Yingshan formation Yingshan formation and fracture-cavity reservoir in the middle Ordoviaian Yijianfang formation are the researching targets in this paper, drawing lessons from past researches of carbonate reservoir, the emphasis is changed from the researches on"point"to researches on"face", the main thinkway of research is confirmed that"seeking benefit facies zones→confirming benefit reservoir→researching properties of reservoir filud". Integratly using information of geology, log, seismic and so on, researches are carried out including distribution principle of benefit lithology, model construction of different types of reservoir, fine structural interpretation, fault combination, paleogeomorphogloic analysis, seismic facies analysis, prediction of reef-shoal sedimentary facies, division of fassil karst, prediction of benefit karst zones, extraction of multi seismic attributes and optimition of effective ones through principal component analysis, poststack wave impedance inversion with the integration of seismic and wells, prediction of fault/micro-fault developmental zones of using technique of multiple dimensioned crack identification such as coherence, similarity, body-curvature and other attributes, description of reservoir space using 3D visualization, which are used for seismic reservoir integrated evalutation, confirmation of benefit exploration areas and providing of drilling targets, which are under the guide of theories of multidisciplinary including petrophysics, geophysics and seismic reservoir prediction and on the base of research result and analysis of sedimentary and structure. Through the application research of new techniques and new methods of reservoir prediction in the research area, assorted techniques series of carbonate reservoir prediction is summarized and quantification of reservoir description is gradually realized. Integrating the results of technologies and methods mentioned above and drawing the superposition map of predicted benefit zones, the reservoir are classified as three types and the main standards of classification are emphasized by the different kind of reservoir in research areas; Proving the theory and technical support for research of carbonate reservoir prediction in Tazhong area through the contrast and summary of the characters of seismic attributes and applicability of methods and techniques of carbonate reservoir in each working area of Tazong area; Verifying the benefit prosects of marine facies carbonate reservoir exploration in Ordovician system of non-main part of No.1 slope break belt of Tazhong area and expanding the depth and scope of reservoir prediction in Tazhong area by the synthetically research of Tazhong researching areas in Tarim basin. This research obtains a preferable effect and a sort of seimic prediction techniques of carbonate reservoir and an assorted workflow are initially formed, which can provide important reference value for researches in similar areas.