Abstract: The present invention provides a method which avoids the expense and danger of previous methods used to discover gas contained in geological formations to be mined. Specifically, it has been found that increasing gas contents of evaporite samples emit increasing levels of sound when dissolved in water. By recording the sounds given off by small grab samples taken from within the mine and from the specific formation to be mined, the volume of gas in the sample can be ascertained and gas liberation during mining operations may be predicted. The method comprises the steps of: obtaining a sample; placing it into water and placing the water and sample into a sound-proof chamber; recording the acoustic emissions given off as the sample dissolves; using the recorded acoustic emissions to determine the presence and volume of gas in the sample; and predicting the volume of gas in the evaporite formation to be mined.

Abstract: The method disclosed herein relates to the removal of unwanted gases and associated fluids in underground mining operations by utilizing mine boreholes. After the mine borehole has been drilled its desired distance from the mine face, an inflatable packer assembly is inserted therein and placed to the end remote from the mine face. This assembly is made up of at least two spaced inflatable packers wherein the spacer between the packers in conjunction with the borehole defines an isolation zone. Fluid conduit members, suitably supported at the mine face, extend into the borehole and act as supply lines from the two separate fluid sources for the packer assembly and isolation zone. A fracturing fluid under high pressure is supplied to the isolation zone and an inflatable fluid is supplied to the at least two packers to rigidly mount them in the borehole. After a fracture is induced in the zone, an additional amount of fracturing fluid is injected thereinto to extend the fracture.