Preliminary studies of Cleat Fractures and Matrix Porosity in Lakhra and Thar coals, Sindh, Pakistan
Keywords:
Cleats; CBM; Micropores; adsorption and absorption ratioAbstract
Cleats are joints and fractures or linear discontinuities forming a structural fabric that develops in coal as a result of physical and chemical changes and tectonic stresses during coalification. The cleats are known to influence the occurrence, migration, and production of coal bed methane. Cleats provide the permeability for fluid flow and successful recovery of coal bed methane gas. Micro pores (matrix) in coal are responsible for the porosity in coal.
Lakhra and Thar coal has been investigated with Scanning Electron Microscopy and results show that in Lakhra coal reticulate cleats and micropores are well developed and has the chance of having methane gas, while Thar coal due to minute size of micro pores and occurrence of micro cleat the chance of coal bed methane diminishes.
However; detailed study of cleat geometry and porosity percentage will further investigate potentials of CBM in lignitic coal of Sindh.
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