The Application Of Stochastic Modeling In Cbm Exploration And Development Research

The thesis establish visual geological model using the stochastic simulation technique, and make a fine description of coal bed methane reservoir, this offer reference for CBM exploration and development。Depending on the current status of coal bed methane exploration and development in China and foreign counties, especially combined with the author’s recent work practice in Hancheng area, analyze the distribution of coal rank, properties of coal petrography and characteristics of coal quality, the region has high coal seam maturity, Ro is generally between1.8%-2.1%, mostly lean coal, a small amount of coal for the poor; Vitrinite content is high, accounting for69%, secondly, inertinite is accounting for19%, the whole region has no exinite.Make Formation stratigraphic classification and correlation, we think the end of the5#coal seam as the bottom of the Shanxi Formation, the end of11#coal seam as the bottom of Taiyuan Formation, and the formation of Shanxi and Taiyuan is classified into Lower Permian; Analyze the region’s sedimentary environment through a single well deposition and on-site core observation, that Shanxi Formation is meandering river deposits and Taiyuan Formation belongs to land and sea deposits which is cross each other. Based on the standardization of log curve in the region, study the relationship between industrial composition of coal reservoirs, physical parameters, gas content and well logs, they have certain relationships with density、natural gamma、resistivity curve, and establish the model of quantitative interpretation; Calculate parameter values of various properties through the quantitative interpretation model, and make variogram analysis in the Petrel software, based on the structure model, select appropriate randomized algorithms to make stochastic simulation of the property parameters.Contrast to3#、5#and11#coal seam, the simulation shows:3#is the thinnest, average thickness is1.60m, ash content is the highest with average content23.63%, coal and rock evolution degree is relatively low, the average of Ro is1.96%, gas content is at the middle level, average gas content10.95m3/t;5#has medium thickness, average thickness is2.75m, ash content is lowest with an average content of19%, coal and rock evolution degree is middle, average Ro is1.98%, gas content is lowest with an average content9.69m3/t;11#is the thickest, average thickness is5.03m, medium ash content with an average content of21.34%, coal and rock evolution level is highest, average Ro is1.99%, and the gas content is highest, average content11.15m3/t.