Sand Boil
A “Sand Boil” is a cone-shaped deposit of sand that is formed during an earthquake. A Sand Boil occurs when subsurface sand layers liquefy and are then blown to the surface through cracks.
A “Sand Boil” is a cone-shaped deposit of sand that is formed during an earthquake. A Sand Boil occurs when subsurface sand layers liquefy and are then blown to the surface through cracks.

Vapor Intrusion Vapor Intrusion occurs when harmful soil contamination changes phase from liquid to vapor underground and moves upward through geologic layers and building foundations, accumulating within indoor air.

Surface-Wave Magnitude “Surface-Wave Magnitude” is the magnitude of an earthquake that scientists estimate using measurements of the amplitude of surface waves.

Oblique-Slip Fault Oblique-Slip Fault: In geology, an oblique-slip fault is a fault that moves parallel to the strike or dip of the fault plane.

Juvenile Water Juvenile Water: In geology, juvenile water is water derived directly from magma, introduced into the Earth’s surface through geological processes such as magmatic and volcanic activity. Since juvenile water is derived from Earth’s center, its characteristics, are associated with higher temperatures and pressures.

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.

Trench Dam Trench Dam: Per the Los Angeles Department of Building and Safety (LADBS) Methane Code, Ordinance Number 175790, a trench dam is part of a methane mitigation system. A trench dam is essentially a subsurface barrier that exists within a furrow or ditch, that is adjacent to the foundation of a building in a…