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.

Thrust Fault Thrust Fault: In the field of geology, a thrust fault is a reverse fault in which the fault plane dipping angle is less than 45 degrees. Thrust faults are dip-slip faults, and can also be listric faults. For instance, the fault underlying the western embankment of the historical St. Francis Dam in Saugus,…

Tsunami Tsunami: In the seismology branch of geology, a tsunami is an oceanic wave (gravitational) that is produced by seismic activity on the ocean floor. Common triggers of tsunamis are large-scale short duration earthquakes, volcanic eruptions, or other submarine earth movements such as subsidence and slope failure.

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…

Active Methane Mitigation Active Methane Mitigation: Active systems refer to the mechanical and electrical components of a methane mitigation system. In fact, the definition of an Active System is available in Methane Code (Ordinance No. 175790). This is a publication by the Los Angeles Department of Building and Safety (LADBS). Moreover, further descriptions of an…

Monoculture Definition The term “Monoculture,” in the fields of farming and agriculture, refers to a cultivation system that comprises only one organism. For instance, an entire crop field that only grows carrots. In a monoculture, there is no symbiosis between different species. As a result, there isn’t any comingling with other organisms. In fact, for…

Dry Density (ρd) “Dry Density” (ρd) is a value that represents the density of soil when it is completely dry. To illustrate, it equates to (“bulk density” / 1) + “water content.” This is a common geotechnical engineering laboratory procedure. Dry Density Formula Dry Density = [(Bulk Density ÷ 1) + (Water Content)]