Propylitic Alteration

A term borrowed from studies of hydrothermal ore deposits that refers to an assemblage of secondary hydrothermal minerals which forms in igneous rocks. This assemblage is made up of chlorite, illite, feldspar (both Na and K-rich varieties), epidote, calcite and pyrite, imparting a dark green tint to the appearance of altered rocks. It is commonly developed in volcanic-plutonic sequences that host high-temperature geothermal reservoirs.

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Word of the Week – Tephra

Word of the Week – Tephra

Tephra Airborne particles of rock and ash produced by an explosive volcanic eruption. Tephra commonly deposits as a blanket that drapes over the underlying topography.

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Word of the Week – THMC

Word of the Week – THMC

THMC Acronym that stands for thermal, hydrological, mechanical, and chemical effects that is evaluated simultaneously when running numerical simulations of reservoir behavior during...

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