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

Leaking Underground Storage Tank (UST) Leaking Underground Storage Tank (LUST): A leaking underground storage tank (LUST) is a known case of hazardous liquid materials released into the environment, from within an underground storage tank (UST) source. The term “LUST” commonly applies to gasoline station soil contamination cases overseen by environmental regulatory agencies. Also See: Underground…

Control Panel in a Methane Mitigation System Control Panel of a Methane Mitigation System: A methane mitigation control panel is the brain behind the active mitigation system. In accordance with the Los Angeles Department of Building and Safety (LADBS) Methane Code, Ordinance Number 175790, a control panel synchronizes methane alarm units with sensors and the…

Hydrogen Sulfide Soil Gas (In Natural Gas) Hydrogen Sulfide: Hydrogen sulfide (H2S) soil gas geologically occurs upon the thermal and microbial decomposition of subsurface organic material deposits. It is typically identifiable in biogenic and petrogenic natural gas sources, along with higher concentrations of methane soil gas. Additionally, nitrogen, oxygen, hydrogen, ethane, and isobutane exist within…

Liquid Limit (LL) “Liquid Limit (LL)” in the field of geological engineering, refers to the upper limit of the “plastic state.” This is a separation of the plastic phase and viscous liquid phase when measuring soil consistency. Mathematically, it is the water content (basing on the percent of dry weight), at which two sections of…

Degree of Saturation (SR) “Degree of Saturation” (SR) is an engineering geology term and refers to the ratio of the volume of water to the total volume of void space. The Degree of Saturation or SR-value ranges from 0% to 100% (0% being completely dry, and 100% being fully saturated). Degree of Saturation Formula Degree…

Seiche Definition The term “Seiche” in geology refers to a wave-oscillation, that comes from any surface body of water, that is initiated by an earthquake or changes in atmospheric pressure. For instance, the rippling waters of a lake or at the bay of an ocean.