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In situ coal gasification using chemical high explosives to fracture coal at depth is described. The one-dimensional Lagrangian elastic-plastic brittle-failure computer program SOC is used to compute epsilon/sub f/, the total failure-induced shear strain, for coal. epsilon/sub f/ is then associated with shot-induced fracture in coal and the corresponding permeability change. In laboratory experiments permeability was measured as a function of radius from the shot, postshot. Epoxy was injected into the shot hole, the coal sectioned, and the observed cracks compared with calculations. The shot-induced cavity radius agreed well with the calculated value. The radius for major changes in appearance of the coal corresponded to an epsilon/sub f/ of about 0.05, and the epoxy-filled fracture radius to about 0.02. Permeability data are questionable, but significant increases were observed to an epsilon/sub f/ of 0.005. The primary measurements in the field experiment were preshot and postshot permeability, preshot and postshot fracture frequency in cores, acoustic velocity as a function of depth, penetration of dye from the shot hole, ease of drilling post-shot holes, attenuation of acoustic waves pasing through the shot region, and electrical resistivity and attenuation of electrical signals passing through the shot region. All of these measurements were made as a function of radius. Increased permeability, increased fracturing, increased acoustic attenuation, decreased sound speed, easier drilling, and dye from the shot hole were found within a radius corresponding to an epsilon/sub f/ of about 0.01. Laboratory and field experiments were found to agree within measurement uncertainty, and it appears that calculated epsilon/sub f/ can be associated with shot-induced effects within reasonable error.