Dilatancy
“Dilatancy” is the increase in the bulk volume of a soil substance during deformation. Dilatancy is caused by the change from a close-pack structure to an open-pack structure.
“Dilatancy” is the increase in the bulk volume of a soil substance during deformation. Dilatancy is caused by the change from a close-pack structure to an open-pack structure.

Focus (Hypocenter) Focus (Hypocenter): In the seismology branch of geology, a focus, or hypocenter, refers to the specific place where an earthquake rupture originates. The focus, or hypocenter, underlies the epicenter when an earthquake occurs at a dip-slip fault, strike-slip fault, oblique-slip fault, or listric fault. In the event of an earthquake, geologists, and seismologists…

Body-Wave Magnitude Body-Wave Magnitude: A method for determining earthquake size from the amplitude of body waves. The body-wave magnitude focuses on P-waves and S-waves, which travel faster through the Earth’s crust and mantle.

Waterproofing Barrier System Definition A waterproofing barrier system guarantees full protection to walls, foundations, and methane mitigation systems that are below grade and are susceptible to moisture penetration. Typically, the best way to protect a retaining wall against moisture is the application of a waterproofing barrier on the backside of it, after pouring concrete, but…

Thrust Fault Thrust Fault: In the field of geology, a thrust fault is a reverse fault in which the fault plane dipping angle is less than 45 degrees. Thrust faults are dip-slip faults, and can also be listric faults. For instance, the fault underlying the western embankment of the historical St. Francis Dam in Saugus,…

Regression Regression: In geology, regression is the formation of a specific sequence of sedimentary and metamorphic layers, that are the result of ocean water withdrawing from the land. To illustrate, when regression occurs over millions of years, geologists find a layer of limestone, overlain by shale, and overlain again by limestone. The opposite of regression is…

Seismology Seismology: (seis·mol·o·gy) a branch of geology and geophysics that relates to earthquakes, including but not limited to their causes, effects, hazards, and mitigation techniques. Seismologists at the United States Geological Survey (USGS) use cutting-edge technology to measure seismic wave properties and geological hazards that trigger them or are triggered by them. In turn, seismology…