Rigidity Definition Rigidity – In geotechnical engineering and engineering geology, rigidity represents the ratio of the shear stress and the amount of angular rotation that it produces, within a rock sample.

Index Fossil Definition An Index fossil, in the field of paleontology, refers to a fossil that identifies and dates the stratigraphic unit that it is observed to exist in. Index fossils can combine a wide geographic range. And they can really narrow down the classifications of most stratigraphic units.

Hydro-Geology (Hydrogeology) Hydro-Geology (Hydrogeology): Hydrogeology is a branch of geology that relates to the study of the earth’s natural groundwater and surface water systems. Whereby geologists study the physical and chemical properties of unconfined aquifers, confined aquifers, river systems, lake beds, oceanwater, natural geysers, and more.

Volcanology Volcanology: Volcanology is a branch of geology that focuses on the study of volcanos. In volcanology, geologists conduct field and laboratory investigations to learn about continental, coastal, and submarine volcanic activities. In fact, volcanology ties into many other branches of geology. For instance, a volcanologist may study the geochemistry of igneous rocks, such as…

Alquist-Priolo Earthquake Fault Zoning Act Alquist-Priolo Earthquake Fault Zoning Act: The Alquist-Priolo Earthquake Fault Zoning Act is a law that assists geologists to define “active faults” versus “potentially active faults.” The process entails using the same aging criteria as the United States Geological Survey (USGS) and the California Geological Survey (CGS). In fact, California policy requires…

Settlement Definition In the field of geology, The term settlement means a gradual downward movement of the ground surface. This is generally due to soil compression at on a larger scale, atdepths that are below the ground surface.