The controlling effect of extremely thick igneous intrusions on coal and gas outburst
Abstract：Twelve fresh coal samples taken from mine numbers 7, 8, 9, and 10 under the Haizi extremely thick igneous rock were analyzed. The tests included proximate analysis, mercury porosimetry, and a quantitative analysis of the maceral. The relationship between the physical parameters and the location relative to the thick sill was established. The results show that volatile matter in the coal decreases, but ash increases, at locations near the sill. Surface area and porosity first increase and then fall abruptly when approaching the sill. This reflects magmatic intrusion into the coal seam. Vitrinite reflectance values increased nearby substantial intru- sions, as did coal rank and maturity. A thermal alteration halo is observed as far as 168 meters from the sill boundary, which is 1.4 times the sill thickness. The intrusion sill acts as a reservoir seal under which gasses are trapped that renders the coal seam prone to coal and methane outburst.
Keywords：extremely thick igneous rocktrapping effectcoal and gas outburstmacerall Vit-finite reflectance
Publication Date：2012-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：6( 42-47 )