In the field of geology, a rock stratigraphic unit, or a lithostratigraphic unit, is a geologic formation that is identifiable by a specific lithology, as well as a consistent stratigraphic position. For example, the Monterey Formation is a rock stratigraphic unit, as it tends to consistently comprise the same gravel and sand types, and consistently makes contact with other geologic formations, as it spans across the entire western portion of California.
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…
Poorly Graded Soil Poorly Graded: In the soil classification process of geology, poorly graded soil represents a sedimentary soil sample that only displays one or a few of the numerous other possible grain sizes for that soil classification, in accordance with the Unified Soil Classification System (USCS). For example, a poorly graded sand (SP) may…
Degree of Saturation (SR) “Degree of Saturation” (SR) is an engineering geology term and refers to the ratio of the volume of water to the total volume of void space. The Degree of Saturation or SR-value ranges from 0% to 100% (0% being completely dry, and 100% being fully saturated). Degree of Saturation Formula Degree…
What is a Concrete Arch Dam? A Concrete Arch Dam is a curved freshwater-retaining structure that is concave in the hydro-geologically down-gradient direction, and uniformly thick from the base to top. With Concrete Arch Dams, a major part of the water load value gets distributed to the abutments of the dam. Thus, Concrete Arch Dams…
Aphanitic Definition Aphanitic: In geology, the term aphanitic describes the texture of plutonic or volcanic igneous rocks, with grains that are not visible to the naked eye. In fact, an aphanitic texture is usually the result of faster cooling and solidification of liquid magma.
Juvenile Water Juvenile Water: In geology, juvenile water is water derived directly from magma, introduced into the Earth’s surface through geological processes such as magmatic and volcanic activity. Since juvenile water is derived from Earth’s center, its characteristics, are associated with higher temperatures and pressures.
