Dilatancy
“Dilatancy” is the increase in the bulk volume of a soil substance during deformation. Dilatancy is caused by the change from a close-pack structure to an open-pack structure.
“Dilatancy” is the increase in the bulk volume of a soil substance during deformation. Dilatancy is caused by the change from a close-pack structure to an open-pack structure.

Petrogenic Gas Petrogenic Gas: In geology, petrogenic gas refers to natural gas that is the byproduct of the thermal decomposition of biological and organic matter. In fact, this is the same process that results in the geological formation of petroleum underground. For instance, methane soil gas hazards in Los Angeles Methane Zones are typically resulting…

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

Time Stratigraphic Unit Definition A Time Stratigraphic Unit, or a Chronostratigraphic Unit, is a rock unit that is characterized by geological formations, during a specific period of time. This serves as a reference for all rocks formed during the same time period.

Perforated Horizontal Pipe in Methane Mitigation Perforated Horizontal Pipe: As per the Los Angeles Department of Building and Safety (LADBS) Methane Code, Ordinance Number 175790, a perforated horizontal pipe is a PVC or ABS pipe that contains a series of small holes or narrow openings placed equidistantly along the length of the pipe, and is…

Environmental Professional Definition Environmental Professional: As per the EPA’s All Appropriate Inquiries Rule, an environmental professional is an environmental consultant that has an accredited education in earth or natural science, at least five years of formal training under another environmental professional, a professional state license, and maintains expert knowledge in the environmental geology, sustainability, and…

Hydro-Compaction Definition (Hydrocompaction) The term “Hydro-Compaction” or “Hydrocompaction” in engineering geology refers to the process whereby soils collapse upon saturation. Hydrocompaction can also be called “Hydro-Consolidation.”