Normal Fault Normal Fault: In the field of geology, a normal fault is a type of dip-slip fault where the hanging wall moves downwards from the footwall. The average dipping angle of a normal fault ranges from 45 to 90 degrees. Normal faults are the opposite of reverse faults. Detachment Fault Detachment Fault: A detachment…

Design Methane Pressure (Soil Formation Pressure) Design Methane Pressure or Soil Formation Pressure: As per the Los Angeles Department of Building and Safety (LADBS) Methane Code, Ordinance Number 175790, Design Methane Pressure means the highest observed measurement of soil formation pressure during the methane testing process. In fact, a Design Methane Pressure measurement that is…

Unconfined Aquifer Unconfined Aquifer: In the hydrogeology branch of geology, an unconfined aquifer is an aquifer that has a water table. In fact, an unconfined aquifer can only be the uppermost hydrogeologic unit and is particularly one that has no hydraulic head (or pressure) that is equal to atmospheric pressure. To illustrate, depth to groundwater…

Strike-Slip Fault or Transform Fault Strike-Slip Fault (Transform Fault): In the field of geology, a strike-slip fault, or a transform fault, is a fault in which movement is parallel to the strike of the fault plane. The opposite of a strike-slip fault is a dip-slip fault. Left-Lateral or Right-Lateral Strike-Slip Fault A transform fault can…

Biogenic Gas Biogenic Gas: In geology, biogenic gas refers to natural gas that is the byproduct of the microbial decomposition of biological and organic matter. For instance, methane soil gas on Earth is typically a biogenic gas resulting from the decomposition of organic soil zones, landfills, marshes, and swamplands. Alternatively, natural gas can be petrogenic…

Impervious Membrane in Methane Mitigation Impervious Membrane: In accordance with the Los Angeles Department of Building and Safety (LADBS) Methane Code, Ordinance Number 175790, an impervious membrane is a continuous methane gas barrier. It is a crucial part of the methane mitigation process and underlies a building to impede the vapor intrusion of methane soil gas….