Thermal Liability of Hyaloclastite in the Krafla Geothermal Reservoir, Iceland: The Impact of Phyllosilicates on Permeability and Rock Strength

Figure 7

Porosity control on UCS, TXL, UTS, and Young’s modulus. (a) Comparison of UCS, TXL, and UTS peak strength of hyaloclastite for each treatment temperature. All strength test types show weakening associated with increased TT and porosity. (b) UCS results follow the general trend for igneous rocks, with TT decreasing strength proportional to the porosity increase. However, TT increases porosity, whilst hyaloclastite densifies and strengthens with depth (values show depth of sampling; [63]). (c) UTS results, regardless of TT, also fall within the general trend for igneous rocks. (d) Young’s modulus from the UCS and TXL tests follow the general trend for igneous rocks (values show depth of sampling; [63]).

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