Twinning Definition Twinning is the observed intergrowth of multiple crystals in a symmetrical fashion. This term applies to the examination of rock thin sections, in the field of optical mineralogy.

Consistency The term “Consistency” in the fields of engineering geology and geotechnical engineering means the degree of adhesion between soil particles within a sample, that are observed to resist deformation or rupture.

Runoff (R) The term “Runoff” (R) in hydrogeology and geology refers to the part of rainfall which accumulates on the ground surface and naturally forms into flowing streams.

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.

Poorly Graded Soil Poorly Graded: In the soil classification process of geology, poorly graded soil represents a sedimentary soil sample that only displays one or a few of the numerous other possible grain sizes for that soil classification, in accordance with the Unified Soil Classification System (USCS). For example, a poorly graded sand (SP) may…

Well Log (Boring Log) Well Log: A geological well log (or boring log) is a detailed record of subsurface materials encountered during a drilling project. Boring logs, or well logs, are written by a geologist, and describe the physical subsurface characteristics and lithological units encountered during well-plotting. Well logs include information about depth, different formations,…