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 transgression is regression.
Hydraulic Head Hydrualic Head: In the field of hydrogeology, hydrualic Head is a measure of the potential energy of a fluid at any given point in a hydraulic system. It explains the potential energy driving fluid flow by summing the elevation of the fluid and the pressure it exerts.
Darcy’s Law In the field of geology, Darcy’s Law is the universal and basic equation representing groundwater flow through a study area. Darcy’s Law Formula Q = KiA The following variables and coefficients apply to this formula: “K” = Hydraulic Conductivity; “Q” = Discharge Rate; “A” = Area of Cross-Section that Water Flows;
Single Station Methane Gas Detector Single Station Methane Gas Detector: As per the Los Angeles Department of Building and Safety (LADBS) Methane Code, Ordinance Number 175790, a single station methane gas detector is a device consisting of electrical components that are capable of measuring methane soil gas concentrations indoors, and initiating an alarm. The single…
Connate Water Definition Connate Water: In geology, connate water is groundwater that has been trapped within the pore space of a sedimentary rock since its original deposition. Connate water is also referred to as “fossil water” due to a long history of non-exposure.
Recurrence Interval Meaning In the field of geology, the term “Recurrence Interval” refers to the average time interval that occurs between two recorded events of seismic activity, of equal magnitude, along the same fault.
Epicenter Epicenter: In the seismology branch of geology, an epicenter of an earthquake is the point on Earth’s surface that is directly above the focus (or hypocenter). It is the ground surface location overlying where an earthquake rupture originates within a dip-slip fault or strike-slip fault. Shortly after an earthquake, United States Geological Survey (USGS)…
