Asthenosphere Asthenosphere: The asthenosphere underlies the lithosphere. The Asthenosphere comprises the upper mantle, where isostatic adjustments are made, and where magma is generated. It is also in this part of the earth, where seismic waves strongly attenuate.

Hydraulic Conductivity (K) “Hydraulic Conductivity” (K), in hydrogeology and hydrology, represents the capacity of a porous medium (such as soil) to transmit water, as per Darcy’s Law. To illustrate, the rate at which fluid can move through a permeable medium (such as soil), depends on the properties of that soil (such as intrinsic permeability) and…

Geosyncline Geosyncline: In geology, a geosyncline is a large-scale indentation in the Earth’s crust that is filled with sediments. A geosyncline forms due to the gradual sinking of the Earth’s crust, causing sediment from adjacent areas to gather inside. An example of a geosyncline is the Appalachian Mountains.

Topple Definition Topple – Slope movement due to forces that cause an overturning moment about a pivot point below the center of gravity of the unit.

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…

Impervious Membrane in Methane Mitigation Impervious Membrane: In accordance with the Los Angeles Department of Building and Safety (LADBS) Methane Code, Ordinance Number 175790, an impervious membrane is a continuous methane gas barrier. It is a crucial part of the methane mitigation process and underlies a building to impede the vapor intrusion of methane soil gas….