Figure 4
From: Cloud-fracture networks as a means of accessing superhot geothermal energy
An excellent fracture pattern, representing a cloud-fracture network, following the first experiment at 450 °C under normal-faulting stress. (a) The sample impregnated with the fluorescent resin. (b,c) Even blue fluorescence over cross-sections of both the σ1–σ2 and σ1–σ3 planes of the sample. (d–l) Optical microphotographs of a thin section of the σ1–σ2 plane cross-section near and far from the borehole, using uncrossed polarized, crossed polarized and UV light.
