Growth Fault Growth Fault: In geology, a growth fault is a strike-slip fault or dip-slip fault that moves contemporaneously with deposition. This causes the throw (amount of vertical displacement) to increase with depth and the strata to be thicker on the downthrown side as compared to the upthrown side.

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,…

Hardpan (Caliche) “Hardpan” is a highly dense and solid layer of soil near the ground surface, which is usually comprised of clay or silty-clay soils. Hardpan forms by cementation over time, during the process of precipitation of insoluble substances such as calcium carbonates, silica, iron oxides, and other organic matter. “Hardpan” is a term mostly…

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…

Unconfined Aquifer Unconfined Aquifer: In the hydrogeology branch of geology, an unconfined aquifer is an aquifer that has a water table. In fact, an unconfined aquifer can only be the uppermost hydrogeologic unit and is particularly one that has no hydraulic head (or pressure) that is equal to atmospheric pressure. To illustrate, depth to groundwater…