Volcanic Rock (Igneous) Definition A “Volcanic Rock” is an igneous rock that is finely crystalline and glassy (or aphanitic). To illustrate, volcanic rocks result from volcanic action at the earth’s surface. Typically, this also includes igneous intrusions that are “near-surface,” which may otherwise be considered plutonic. This action results in a final rock that is…

Provenance Provenance: In the field of geology, and the branch of geomorphology, the term “provenance” means the place of origin from which the constituent materials of sedimentary rock or facies are derived.

Soil Compaction Testing or Soil Density Testing Soil compaction testing, or soil density testing, is the process by which the density property of a soil mass is increased in the field by various means, and monitored by a professional geologist in accordance with local building department specifications. During the placement of engineered backfill material, density…

Licensed Professional Geologist A “Licensed Professional Geologist” or a “Certified Professional Geologist” is a person who is certified by a State and/or Federal agency (such as the California Department of Consumer Affairs, Board for Professional Engineers, Geologists & Land Surveyors), and has proven be educated, formally trained and professionally competent per government standards, to practice…

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…

Liquid Limit (LL) “Liquid Limit (LL)” in the field of geological engineering, refers to the upper limit of the “plastic state.” This is a separation of the plastic phase and viscous liquid phase when measuring soil consistency. Mathematically, it is the water content (basing on the percent of dry weight), at which two sections of…