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 – Two-Phase Flow

Word of the Week – Two-Phase Flow

Two-Phase Flow A condition that is attained in production wells associated with high temperature (>200°C) geothermal reservoirs, wherein the flowing fluid comprises a mixture of steam...

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Word of the Week – Turbine

Word of the Week – Turbine

Turbine Spinning axle mounted with fan blades that converts a fluid flow stream into mechanical energy. To produce electricity, the mechanical energy from the turbine is connected to a...

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Word of the Week – Unconformity

Word of the Week – Unconformity

Unconformity Geological term that refers to an ancient surface that has been buried and now represents a discontinuity or break between coherent masses of rock or strata.

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