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.

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…

Permeability “Permeability” in engineering geology and geotechnical engineering refers to the property of a soil sample (or porous rock) which relates to transmitting a fluid within. Permeability measures the relative case of flow under unequal pressure. Permeability is calculated using Darcy’s Law.

What is a Concrete Slab and Buttress Dam? A Concrete Slab and Buttress Dam is a freshwater-retaining structure comprising reinforced concrete slabs that are supported in-place by buttresses. The foundation of a Concrete Slab and Buttress Dam receives a large load. Thus, the foundation must be structurally sound, impervious, and competent. The alternative types of dams…

What is an Embankment Dam? An Embankment Dam is a freshwater-retaining structure comprising excavated rock, soil, or a combination of rock and soil from nearby geological formations.  In fact, Embankment Dams are known as an “Earthfill Dam” when filled with soil, and a “Rockfill Dam” when filled with rocks. Earthfill Dams are most common. The…

“Test” Definition in Paleontology In the field of paleontology, a subsidiary of geology, the term “test” refers to the external hard part of an invertebrate.