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…

Silicates Definition In the fields of geology and mineralogy, the term “silicates” refers to compounds whose crystal structure contains SiO4 tetrahedra. Silicates are either isolated or joined to form groups, rings, single or double chains, sheets, or three-dimensional frameworks.

Natural Gas Natural Gas: In geology, natural gas means combustible hydrocarbon gas that forms by natural geological or biological processes. To illustrate, natural gas that forms by geological processes is the thermal decomposition of buried organic materials. Whereas natural gas that forms via biological processes entail the microbial decomposition of buried organic material. Natural gas…

Phaneritic Definition In geology, the term Phaneritic applies to the texture of an igneous rock. A phaneritic plutonic rock has grains that are large enough to be seen with the naked eye. In fact, this indicates there was a slower rate of magmatic cooling.

Asthenosphere Asthenosphere: The asthenosphere underlies the lithosphere. The Asthenosphere comprises the upper mantle, where isostatic adjustments are made, and where magma is generated. It is also in this part of the earth, where seismic waves strongly attenuate.

Water Table Water Table: In the hydrogeology branch of geology, the water table represents the surface of an unconfined groundwater aquifer, where the hydraulic pressure is equal to atmospheric pressure. Additionally, a water table is present in a perched groundwater zone. Although, there is no water table in a confined aquifer.