Ultramafic Definition
In the study of geology, the term “ultramafic” refers to an igneous rock that comprises up to 90% mafic minerals, or more.
In the study of geology, the term “ultramafic” refers to an igneous rock that comprises up to 90% mafic minerals, or more.

Hooke’s Law “Hooke’s Law” is a geological statement relating to the elastic deformation of rocks. Hooke’s Law states the strain of an earth-material is linearly proportional to the applied stress.

Plutonic Rock (Igneous) Definition The term “Plutonic” in the field of geology refers to an igneous rock, wherein the magma had originally cooled, solidified, and crystalized underground. A plutonic rock is generally coarsely crystalline (phaneritic) and is formed during a massive geologic intrusion of magma. In fact, outcropping (or daylighting) plutonic rocks are geologic features…

Surface-Wave Magnitude “Surface-Wave Magnitude” is the magnitude of an earthquake that scientists estimate using measurements of the amplitude of surface waves.

Runoff (R) The term “Runoff” (R) in hydrogeology and geology refers to the part of rainfall which accumulates on the ground surface and naturally forms into flowing streams.

Soil Creep Definition Soil Creep is a type of landslide that entails the slow and gradual movement of a soil mass (or even some loose rock) materials.

Gap-Graded The term “Gap-Graded” is used by geologists, engineers, and soil scientists in the geotechnical engineering field to describe the gradation of a soil sample, specifically when some particle sizes are missing. Aside from being “gap graded,” a soil sample can be described as “well-graded” (also referred to as poorly sorted), or “poorly graded” (or…