Abstract

We present a simple methodology for estimating key petrophysical characteristics of partially molten (igneous) porous media using microgranular (microdiritic) enclaves from the Ross of Mull granite, Scotland, as examples. A number of enclaves have been infiltrated by granitic melt while still partially molten, with the infiltration (porosity) network now preserved as frozen-in granitic melt. By serial sectioning through individual enclaves, we show that the preserved infiltration channel network is interconnected in three dimensions. Using image analysis techniques, we have estirnated the porosity () of individual enclave sections and obtained the variation in porosity with depth. Simple representation of the pore-channel network on a branch and node chart allows useful petrophysical characteristics including the connectivity, genus and tortuosity of the network to be estimated. Computer-enhanced reconstructions of the pore network in three dimensions are shown that provide a powerful way of visualizing complex geometries in porous media.