Transgression Transgression: In geology, the term transgression is the formation of a specific sequence of sedimentary and metamorphic layers, that are the result of ocean water advancing onto land. To illustrate, when transgression occurs over millions of years, geologists find a layer of sand, overlain by shale, and overlain again by limestone. The opposite of…

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…

Contact Metamorphism Contact Metamorphism – Metamorphism is associated with the intrusion of an igneous mass. Metamorphic changes are caused principally by heat, but also by magma composition and deformation related to the intrusion. Pressures are relatively low (<3000 bars) while temperatures range from 200°C to 1000°C.

Perched Groundwater Perched Groundwater – In geology, “perched groundwater” refers to unconfined groundwater which separates from an underlying body of groundwater by an unsaturated zone or vadose zone.

Zoning Mineralogy Definition Zoning is a variation of crystal composition that is a characteristic of feldspars. To illustrate, the center of a feldspar mineral is formed by a high-temperature phase, whereas the exterior is formed by a low-temperature phase.

Zeolites Definition In geology, zeolites are a group of hydro-alumino-silicate minerals that are compositionally analogous to the feldspars. Zeolites typically comprise sodium (Na), calcium (Ca), or potassium (K) as chief metals. And zeolites also tend to develop within basalt cavities, lake sediments, oceanic sediments, and volcanic tuff. Modern Economical uses of the Zeolites Modernly, zeolites…