Twinning Definition
Twinning is the observed intergrowth of multiple crystals in a symmetrical fashion. This term applies to the examination of rock thin sections, in the field of optical mineralogy.
Twinning is the observed intergrowth of multiple crystals in a symmetrical fashion. This term applies to the examination of rock thin sections, in the field of optical mineralogy.

Regression Regression: In geology, regression is the formation of a specific sequence of sedimentary and metamorphic layers, that are the result of ocean water withdrawing from the land. To illustrate, when regression occurs over millions of years, geologists find a layer of limestone, overlain by shale, and overlain again by limestone. The opposite of regression is…

Seismic Moment Seismic Moment: In the seismology branch of geology, seismic moment represents a measure of the size of an earthquake, depending on the area of rupture, the rigidity of the rock, and the amount of slip from faulting.

Cation Cation: In the fields of chemistry and geochemistry, a cation is a positively charged ion. The oppositely charged ion is an anion.

Transgression Transgression: In geology, the term transgression is the formation of a specific sequence of sedimentary and metamorphic layers, that are the result of ocean water advancing onto land. To illustrate, when transgression occurs over millions of years, geologists find a layer of sand, overlain by shale, and overlain again by limestone. The opposite of…

Atmosphere Atmosphere: The atmosphere of a terrestrial planet is an outermost series of layers that comprises gaseous phase elements within part of the planet’s gravitational field. For instance, the Earth’s atmosphere exists in the air spaces that are approximately 95 kilometers above the ground surface. And within it, are the troposphere, stratosphere, mesosphere, and thermosphere….

Soil Compaction Testing or Soil Density Testing Soil compaction testing, or soil density testing, is the process by which the density property of a soil mass is increased in the field by various means, and monitored by a professional geologist in accordance with local building department specifications. During the placement of engineered backfill material, density…