A 9-hour circulation test that followed stimulation proved fluid flow and energy transfer from an EGS reservoir in hot dry granite …
Mineral Geothermometer
A secondary mineral phase whose stability is defined by a lower and sometimes an upper temperature threshold. Common mineral geothermometers comprise clays, zeolites and epidote, with crystal structures that contain a hydroxyl (OH–) or water (H2O) molecule. The temperature ranges of mineral geothermometers are calibrated from investigations of a large number of drilled geothermal resources where mineral zonations and temperature gradients have been determined.
Geothermal Glossary
Word of the Week – Diorite
Diorite Dark colored, coarse grained, intrusive rock that contains less silica than granite and that is mostly made of plagioclase, biotite, hornblende, pyroxene, and minor to nil quartz.
Word of the Week – Direct Use
Direct use The utilization of geothermal heat as an energy resource, e.g., to heat (or cool) a building such as a greenhouse, for drying, for manufacturing.
Word of the Week – Directional Drilling
Directional Drilling The practice of steering the trajectory of a well during drilling from vertical to a deviated angle, including horizontal drilling used for oil and gas production from poorly permeable rocks. Directional drilling may also be used to maneuver...