Recovery of tectonic traces and its influence on coalbed methane reservoirs: A case study in the Linxing area, eastern Ordos Basin, China

摘要

The physical properties of coal reservoirs, i.e., porosity, permeability, fractures, and coal structures, are generally evaluated based on its structural morphology, however, its tectonic evolution history plays a much more important role. The key problems associated include the time when the dominant variations on properties of coal occurs and how to quantitatively characterize the influences of different tectonic movements. Based on field joint observations and well logging (micro-resistivity imaging logging (MIL), interval transit time (DT24), density (DEN), and natural gamma-ray (GR)) interpretations, the paleotectonic stress fields and tectonic traces were recovered and the present coal structures were identified. Subsequently, the quantitative correlation between the tectonic deformation and coal reservoir property were established with fluid intrusion tested porosity and permeability and scanning electron microscope (SEM) results.