Contact Metamorphism Contact Metamorphism – Metamorphism is associated with the intrusion of an igneous mass. Metamorphic changes are caused principally by heat, but also by magma composition and deformation related to the intrusion. Pressures are relatively low (<3000 bars) while temperatures range from 200°C to 1000°C.

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.

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.

Soil Creep Definition Soil Creep is a type of landslide that entails the slow and gradual movement of a soil mass (or even some loose rock) materials.

Dry Density (ρd) “Dry Density” (ρd) is a value that represents the density of soil when it is completely dry. To illustrate, it equates to (“bulk density” / 1) + “water content.” This is a common geotechnical engineering laboratory procedure. Dry Density Formula Dry Density = [(Bulk Density ÷ 1) + (Water Content)]

Unobstructed Opening Definition in Methane Mitigation Unobstructed Opening: Per the Los Angeles Department of Building and Safety (LADBS) Methane Code, Ordinance Number 175790, an unobstructed opening is a permanent clearance or gap in the walls, floors, or ceiling of a structure, to allow for direct fresh airflow. In methane mitigation plan applications, this does not…