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

Direct Shear Test A Direct Shear Test is a geotechnical engineering laboratory procedure that measures the shear strength value of a soil sample.

Subsidence “Subsidence” is a geologic condition, in which a localized mass movement occurs, resulting in the downward settlement of the earth over time. When subsidence occurs, the actual ground surface elevation is lower. This occurrence of the ground surface sinking is typically caused by groundwater table and aquifer reductions, by which the soils become more…

Seismic Risk Definition Seismic risk is the probability that a subject site will be adversely affected by any seismic hazard, such as an earthquake. Seismic risk tends to increase in areas that are more earthquake-prone and vulnerable to damage. And vulnerability refers to the potential impact on people, as well as properties. For instance, places…

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,…

Wing Dam or Wing Dike A “Wing Dam” or “Wing Dike” refers to a dam that intentionally retains a fraction of the width of a flowing water source. Unlike a conventional dam, a wind dam aims to divert the path of water flow. Additionally, a wing dike can control the velocity of water flow. For…

Methane Soil Gas Methane Soil Gas: In geology, methane soil gas refers to the confinement of CH4 within the interstitial pore spaces of subsurface soils. On Earth and potentially on Mars, methane derives from subsurface pockets of biogenic and petrogenic natural gas. To illustrate, accumulations of buried organic matter decay via microbial or thermal degradation….