The Los Alamos Scientific Laboratory (LASL) is involved in a broad spectrum of oil shale-related activities for the Department of Energy (DOE), including the bed preparation design of a modified in-situ retort. This aspect of oil shale research has been identified by the DOE as one of the limiting technologies impeding commercial, in-situ development of oil shale.

The retort bed must have uniform particle size, permeability, and void distributions to allow proper retorting and optimum resource recovery. Controlled fracturing using chemical explosives and carefully designed blasting schemes are the only feasible methods to attain this distribution. Our approach to the bed preparation problem is a coordinated research program of explosives characterization, dynamic rock mechanics, predictive computer modeling, and field verification tests.

The program is designed to develop the predictive fracturing capability required for the optimum rubbling of the shale. It takes advantage of the large computing facilities at Los Alamos and the considerable expertise in explosives and computer hydrocodes developed here for other energy and national defense programs. As these codes are developed for oil shale and refined, they are tested with field verification experiments. Tests with up to four boreholes and single-decked charges conducted at the Colony Mine in Colorado in conjunction with ARCO and TOSCO, have demonstrated the ability to predict rock behavior. Larger experiments with more boreholes and decked charges will be done at the Anvil Points Mine near Rifle, Colorado. These field tests will calibrate the fracture modeling cod s and confirm their validity to predict explosive fracturing, including the effects of existing joints and fractures in the oil shale. The experiments will also include fluid flow tests to verify the three-dimensional models of multiphase flow that are under development at LASL.

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