Construction of Detailed 3D Geological Model of a Deposit with Difficult Geological Structures on the Basis of Basic Facies Models

Abstract

In Westem-Siberian oil-and-gas bearing basin the basic objects of working out are neocom deposition of sediment. Terrigenous deposition Jurassic the age, containing considerable stocks of hydrocarbonic raw materials, because of complexity of the structure are involved in working out not everywhere. Frequently realized for overlying neocom objects the approach to allocation of the petrosated bodies does not bring positive results at its direct transferring on objects юр ск ог оage (especially deposition of the Tyumen retinue). Deposition of the Tyumen retinue have difficult polyfacial a structure. The density of an explorative grid of chinks within a deposit when distances between chinks exceed some kilometers, is incommensurable to step-type behavior of object of research. At insufficient quantity of an actual material and representation about an object structure in ме жс кв аж ин но мspace only in general the most accessible method of its studying is modeling. For today three-dimensional computer modeling became the necessary tool at the decision of geological problems even at the initial stages of studying of a geological structure of layers The sequence of operations at construction of any three-dimensional geological model is varied, but standard where it is defined by regulating documents each stage and includes drawing up of basic geological model of an investigated site, structural modeling, lithology modeling and modeling of properties. In domestic practice for the present in work single instances on construction of geological and hydrodynamic model are conducted by multidisciplinary groups. Frequently the experts who are directly engaged 3D in modeling, facies modeling approach to a stage formally, being guided qualitative, is more rare the semiquantitative information (it is necessary to formulate correctly) about laws and features of a geological structure of object, and in a choice of methods of modeling, as a rule, are based on already tested receptions. But at modeling of difficult geological objects the insufficient attention to unique features for the given deposition can lead to a number of errors and discrepancies in model. Therefore for objects with a difficult geological structure a defining stage is creation threedimensional digital facies the model correctly reflecting basic facies model of deposition. For construction basic facies it is necessary for model to restore conditions of formation of deposition of a layer, to allocate the basic lithofacies complexes, to reveal laws of distribution sand-siltstone sand- siltstone interlayer in the allocated complexes, to analyse lithology and filtration-capacitive properties of breeds taking into account their accessory to lithofacies to zones, to estimate perspectivity of presence of potential collectors and their qualitative characteristics. In the given work the example facies interpretations and construction three-dimensional facies models of object JC2 of one of deposits of the central part of the Western-Siberian pool is resulted.