Space-Time-Temperature Profiles for Conductive Heat Flow in Country Rock Surrounding Hot Intrusive Bodies
Temperature vs distances profiles during geological time have been calculated for a variety of realistically shaped magmatic bodies intruded into country rock. The calculations were made with a computerized finite difference formulation of the classical time dependent conductive heat-flow equation. The formulation can be adopted to numerous situations. These include: emplacement at different rates, variations in the shape of the intrusion, e.g. domed cylinders, cones, or even arbitrary shapes as determined by field measurements. The intrusions may remain in contact with or become isolated from the magma pool. Also, the thermodynamic properties of the intrusion may be adjusted, e.g. to include latent heat of fractional crystallization. The surrounding rock may be homogeneous or strata of different kinds of rock. The surface above the intrusion may assume any reasonable shape. Faulting in the surrounding rock is being included and magma convection will be added in the future.
Completed calculations of the surface heat-flow gradients are consistent with those found in regions of known geothermal activity. This calculational procedure, in conjunction with local surface and subsurface temperature and heat-flow measurements appears to provide a useful approach to evaluating geothermal energy sources and new techniques for geothermal exploration and characterization.
KeywordsLatent Heat Geothermal Exploration Dike Intrusion Center Fringe Conductive Heat Flow
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