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…

Intrusive Rocks In the volcanology branch of geology, intrusive rocks are igneous rocks that form and crystallize under the Earth’s ground surfaces, within other geologic formations. In fact, intrusive rocks form by the process of magma shooting through pre-existing sedimentary, igneous or metamorphic rocks. For instance, a pegmatite dyke or a batholith. On the other…

Confined Aquifer Confined Aquifer: In the hydrogeology branch of geology, a confined aquifer is an aquifer that is overlain (and underlain) by a layer of low permeability, such as clay, shale, or silty clay. In fact, the two confining layers contain the storage and flow of groundwater, such that the aquifer maintains hydraulic pressure (or…

Sedimentary Rock Definition In geology, the term “Sedimentary Rock” refers to the classification of rock that is the result of the gradual consolidation and deposition of loose particles of other rock classifications (igneous or metamorphic). Alternatively, sedimentary rocks can also form by the accumulation and precipitation of other natural chemical solutions in a depositional environment….

Mineral Assemblages Mineral Assemblages: In the field of geology and the branch of mineralogy, the term “mineral assembles” means the minerals that compose a rock, including the different kinds and their relative abundance.

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…