“Effective Size” (D10) is an engineering geology term. Effective Size represents a diameter that directly corresponds to the percentage, by weight, of grains that equal to 10% on the grain-size diagram. To illustrate, 10% of the soil sample particles are finer-grained, and 90% of the sample particles are coarser than the “effective size.”
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.
Cation Cation: In the fields of chemistry and geochemistry, a cation is a positively charged ion. The oppositely charged ion is an anion.
Regression Regression: In geology, regression is the formation of a specific sequence of sedimentary and metamorphic layers, that are the result of ocean water withdrawing from the land. To illustrate, when regression occurs over millions of years, geologists find a layer of limestone, overlain by shale, and overlain again by limestone. The opposite of regression is…
Underground Storage Tank (UST) Underground Storage Tank (UST): An underground storage tank (UST) is a confined container occupying any volume of space within the subsurface, for the purposes of storing liquid. Underground tanks typically support commercial and residential services and have filling ports, ventilation pipes, and connecting product pipelines. Underground storage tanks (USTs) come in different…
Hydraulic Conductivity (K) “Hydraulic Conductivity” (K), in hydrogeology and hydrology, represents the capacity of a porous medium (such as soil) to transmit water, as per Darcy’s Law. To illustrate, the rate at which fluid can move through a permeable medium (such as soil), depends on the properties of that soil (such as intrinsic permeability) and…
Tsunami Tsunami: In the seismology branch of geology, a tsunami is an oceanic wave (gravitational) that is produced by seismic activity on the ocean floor. Common triggers of tsunamis are large-scale short duration earthquakes, volcanic eruptions, or other submarine earth movements such as subsidence and slope failure.
