Word of the Week – Drill Bit

Drill Bit

A tool that is placed on the end of a string of pipe to drill a well. Rotary drill bits are commonly used in oil and gas and geothermal drilling. Coring bits are used to obtain cylindrical core samples of rock that preserve mineralogical and textural features which are commonly destroyed during rotary drilling.

Word of the Week – Microseismicity


Tiny earthquakes that result from slip or shear along a fracture caused by an uneven distribution of stress. The displacements are very small scale and unfelt at the surface. They can only be detected with sensitive equipment such as geophones and accelerometers, which can be deployed on the surface or in boreholes.

Word of the Week – Granitoid


A generic term referring to hard, coarsely crystalline plutonic rock that is produced by intrusion of magma followed by a long period of slow cooling and solidification below the surface (>10 km depth). The mineralogy and composition are variable, ranging from felsic (e.g., granite) to mafic (e.g., diorite).

Word of the Week – Binary Cycle Power Plant

Binary Cycle Power Plant

A power plant in which the produced geothermal fluid passes through a heat exchanger and heats a low boiling point liquid, commonly an organic compound such as pentane, to vaporize and condense as it passes through a turbine and generate electricity. This is a closed loop power cycle, in which organic working fluid is confined and reused through the heating and cooling process.