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.

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…

Diagenesis Diagenesis: In geology, diagenesis refers to the physical and chemical changes of a sedimentary formation when compaction and lithification occur over time.

Regression Regression: In geology, regression is the formation of a specific sequence of sedimentary and metamorphic layers, that are the result of ocean water withdrawing from the land. To illustrate, when regression occurs over millions of years, geologists find a layer of limestone, overlain by shale, and overlain again by limestone. The opposite of regression is…