In the field of geology, the term “Metamorphic Rock” refers to a rock classification that is the result of the alteration of prior existing sedimentary rocks or igneous rocks. The alteration process is “metamorphosis, and can take place by various methods and environments. The metamorphosis process produces specific metamorphic rocks, on the basis of applied temperature and pressure as well as the geochemistry and chemical content of the original rock.
Regional Metamorphism Regional Metamorphism: Metamorphism acts over large areas resulting from applied pressures of 3,000 to 10,000 bars and temperatures of 400°C to 800°C. Regional metamorphism is also referred to as dynamothermal metamorphism.
Type Section Geologic Definition In geology, the term “type section” refers to a specific stratigraphic unit, that can be compared to other parts of the geologic unit. For a type section, it’s preferred to describe the location where the geologic unit has the maximum thickness, and where the top and bottom units are observable.
Direct Shear Test A Direct Shear Test is a geotechnical engineering laboratory procedure that measures the shear strength value of a soil sample.
Phaneritic Definition In geology, the term Phaneritic applies to the texture of an igneous rock. A phaneritic plutonic rock has grains that are large enough to be seen with the naked eye. In fact, this indicates there was a slower rate of magmatic cooling.
Maximum Soil Screening Levels (MSLs) Maximum Soil Screening Levels (MSLs): MSLs are a list of risk-based hydrocarbon concentrations for soil pollution evaluations, that is developed by the California Regional Water Quality Control Board. These screening levels are based on the Leaking Underground Fuel Tanks (LUFT) Manual, for cleaning up soil contamination from leaking USTs. However, MSLs…
Liquefaction Liquefaction: Liquefaction is the process by which there is: (1) a sudden and significant decrease of shear resistance in a soil sample (cohesion-less); (2) a sudden (but temporary) increase of the pore-water pressure of a substance; and (3) a solid mass of soil that is transformed into a fluid state mass. In the event…
