BS ISO 4657:2022 pdf download – Assessment specification of coalbed methane resources.
BS ISO 4657 specifies the objectives, tasks, work processes, classification, report preparation and acceptance of coalbed methane (CBM) resource evaluation.
5.3.2 Geologic map compiling
On the basis of data collection,collation and analysis,the basic geologic maps shall be compiled for the evaluation of CBM resources,such as coal seam structure contour map,coal seam burial depth map,coal seam isopach map,strati graphic correlation profile and CBM gas content map.
5.3.3 Comprehensive analysis
The geological condition analysis includes the regional tectonic characteristics,sedimentary characteristics,strata and coal seam distribution,coal characteristics and coal rank,coal reservoir characteristics (porosity,permeability,gas content,temperature,pressure,etc.)，rock characteristics of the roof and floor of coal seam and hydrogeological characteristics.They provide a geological basis for the evaluation methods selection and key parameters value assignment.
5.4 CBM resource calculation
The volumetric method shall be used for resource calculation if there is adequacy of geological data which meets requirements of the calculation.
5.4.2 Principles for input parameters value assignment for volumetric method