Alquist-Priolo Earthquake Fault Zoning Act

Alquist-Priolo Earthquake Fault Zoning Act

Alquist-Priolo Earthquake Fault Zoning Act: The Alquist-Priolo Earthquake Fault Zoning Act is a law that assists geologists to define “active faults” versus “potentially active faults.” The process entails using the same aging criteria as the United States Geological Survey (USGS) and the California Geological Survey (CGS). In fact, California policy requires zoning any potentially active fault that possesses a relatively high potential for ground rupture, for future public reference. The law was originally passed in 1972 as the “Alquist-Priolo Special Studies Zones Act.” Currently, it has undergone some reform, and is now referred to as the “Alquist-Priolo Earthquake Fault Zoning Act.”

The Alquist-Priolo Earthquake Fault Zoning Act commonly applies to the seismology, engineering geology, and geotechnical branches of geology.

Fault Investigations

As per the CGS, strike-slip faults and dip-slip faults may be categorized as “active,” “potentially active,” or “inactive.” Active faults show displacement within the past 11,000 years. Potentially active faults show displacement within the last 1.6 million years. And inactive faults show no evidence of displacement within the last 1.6 million years.

Similar Posts

  • Tsunami

    Tsunami Tsunami: In the seismology branch of geology, a tsunami is an oceanic wave (gravitational) that is produced by seismic activity on the ocean floor. Common triggers of tsunamis are large-scale short­ duration earthquakes, volcanic eruptions, or other submarine earth movements such as subsidence and slope failure.

  • Milliequivalent per liter

    Milliequivalent per liter Milliequivalent per liter (meq/L): A unit used to express the chemical equivalence of the concentration of solutes in a solution. It is calculated by dividing the concentration of a substance (in mg/L) by its equivalent weight. This measurement helps in understanding the reactive capacity of ions in the solution.

  • Metamorphic Rock

    Metamorphic Rock Definition In the field of geology, the term “Metamorphic Rock” refers to a rock classification that is the result of the alteration of prior existing sedimentary rocks or igneous rocks. The alteration process is “metamorphosis, and can take place by various methods and environments. The metamorphosis process produces specific metamorphic rocks, on the…

  • Dry Strength

    Dry Strength “Dry Strength” is a value that represents the strength of a soil sample, when dry, as determined by the crushing test. There is a common geotechnical engineering laboratory procedure for determining the cohesiveness or plasticity of a sample with organic or inorganic clays and silts.  

  • Hydrogen Sulfide Soil Gas

    Hydrogen Sulfide Soil Gas (In Natural Gas) Hydrogen Sulfide: Hydrogen sulfide (H2S) soil gas geologically occurs upon the thermal and microbial decomposition of subsurface organic material deposits. It is typically identifiable in biogenic and petrogenic natural gas sources, along with higher concentrations of methane soil gas. Additionally, nitrogen, oxygen, hydrogen, ethane, and isobutane exist within natural…

  • Darcy’s Law

    Darcy’s Law In the field of geology, Darcy’s Law is the universal and basic equation representing groundwater flow through a study area. Darcy’s Law Formula Q = KiA The following variables and coefficients apply to this formula: “K” = Hydraulic Conductivity; “Q” = Discharge Rate; “A” = Area of Cross-Section that Water Flows;