Method for determining gas content of coal bed gas reservoir

Abstract

The invention discloses a method for determining the gas content of a coalbed methane reservoir. First, a gas content calculation model is established according to the response characteristics of the coal core gas content, coal core component ash, density data and logging data measured by experiments, and the original Gas content: Then, considering the impact of structure and hydrodynamic action on gas content, measured formation water salinity measurement data, and established formation curvature calculation formula; using the measured formation water salinity measurement data and the established formation curvature calculation formula to The gas content is corrected to evaluate the current gas content of the coal reservoir. The present invention comprehensively considers the influence of structural strength and hydrodynamic strength in the coal reservoir to obtain the gas content of the coal seam, and can reliably obtain the original gas content of the reservoir based on the experimental component data of the gas content of the coal core, and according to the formation curvature and formation water The salinity data characterizes the impact of structure and hydrodynamics on the gas content of coal reservoirs, evaluates the current gas content, and provides reliable technical support for the current exploration and development evaluation of coalbed methane in my country.

Description

technical field [0001] The invention relates to the field of reservoir evaluation, in particular to a method for determining the gas content of a coalbed methane reservoir. Background technique [0002] With the development of coalbed methane industry and the deepening of coalbed methane exploration and development, the research on logging evaluation methods of coalbed methane reservoirs has been paid more and more attention. Since coalbed methane is a self-generated and self-storage unconventional natural gas, the evaluation methods of coal quality components and gas content are different from conventional logging evaluation methods. Scholars at home and abroad have made many achievements in this field. Take coal components. But there is no effective method for logging evaluation of coal rank and gas content. Predecessors have done a lot of work on gas content calculation, mainly using the Lange equation or the relationship between gas content and depth and using numerica...

AI Technical Summary

Problems solved by technology

However, this method has certain errors and does not consider the impact of later destruction, and structural and hydrodynamic conditions have a very important impact on the content of coalbed methane, but the research on this impact is only at the qualitative stage, and there is no Quantitative Calculation Method

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