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.

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.

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.

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.

Recurrence Interval Meaning In the field of geology, the term “Recurrence Interval” refers to the average time interval that occurs between two recorded events of seismic activity, of equal magnitude, along the same fault.

Ultramafic Definition In the study of geology, the term “ultramafic” refers to an igneous rock that comprises up to 90% mafic minerals, or more.