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.

Latest News

Word of the Week – Numerical Modeling

Word of the Week – Numerical Modeling

Numerical Modeling Application of computational methods to solve complex problems that predict the behavior or the outcome of a real-world or physical system that evolves in space and time.

read more
Word of the Week – Normal Fault

Word of the Week – Normal Fault

Normal Fault High angle fault that results from extensional stress and forms a steeply dipping planar structure. Slip movement during an earthquake is vertical and down dip. The...

read more
Word of the Week – Packers and Plugs

Word of the Week – Packers and Plugs

Packers and Plugs Downhole devices emplaced into a well to seal zones and intervals so they can be pressurized by pumping fluid from the surface in order to stimulate fractures at a...

read more

Utah FORGE

Advancing innovative technologies to unlock Earth’s limitless geothermal energy.