A sudden release of energy in the Earth's crust, most often caused by the abrupt slipping of rock along a fault, generating seismic waves that shake the ground and, in the largest events, can be felt across an entire region. Earthquake magnitude is measured on logarithmic scales reflecting total energy released, while shaking intensity at a given location depends on distance, depth and local geology. The vast majority of major earthquakes occur along tectonic plate boundaries, especially around the Pacific Ring of Fire.
Facts
PeriodicityNot periodic in a fixed sense; most occur as part of a sequence related in location and time to a main shock, producing clusters of aftershocks that can continue well after the initial rupture. 1 ScaleThe first scale for measuring earthquake magnitude, the Richter scale, was developed in 1935; each whole unit on modern seismic magnitude scales represents a tenfold difference in ground-shaking amplitude and roughly a thirty-two-fold difference in energy released. 1 First DescribedThe first scale for measuring earthquake magnitudes was developed by Charles Francis Richter in 1935. 1 Identification
Distinguishing AppearanceThe shaking of the Earth's surface from a sudden release of energy in the lithosphere, ranging from tremors too weak to feel to violent shaking that can propel objects and people into the air and destroy infrastructure across entire cities. 1 Connections
Associated With
Strong seismic shaking from an earthquake is a well-documented direct trigger of snow avalanches on unstable slopes.
Earthquake lights are luminous phenomena reported in the sky during or immediately before earthquake shaking, thought to arise from stress-induced electrical effects in rock; the phenomenon is defined by, and occurs during, the earthquake itself.
Earthquake-triggered landslides are one of the most common and destructive secondary hazards of strong seismic shaking on steep or saturated slopes.
Most destructive tsunamis are generated directly by large undersea earthquakes that vertically displace the seafloor and the water column above it.
Volcanic eruptions are typically preceded and accompanied by volcano-tectonic earthquakes and seismic swarms caused by magma movement through the crust, a mechanistic link volcanologists use to forecast eruptions.
Sources
1. Earthquake (Wikipedia)
WikipediaWikipedia 'Earthquake', Clusters section
Most earthquakes form part of a sequence, related to each other in terms of location and time.
Wikipedia 'Earthquake', Measurement and location section
The first scale for measuring earthquake magnitudes was developed by Charles Francis Richter in 1935.
Wikipedia 'Earthquake', lead section
Earthquakes can range in intensity, from those so weak they cannot be felt, to those violent enough to propel objects and people into the air, damage critical infrastructure, and wreak destruction across entire cities.
Wikipedia 'Earthquake', Measurement and location section (scale sentence)
The first scale for measuring earthquake magnitudes was developed by Charles Francis Richter in 1935. Subsequent scales (seismic magnitude scales) have retained a key feature, where each unit represents a ten-fold difference in the amplitude of the ground shaking and a 32-fold difference in energy.
Wikipedia 'Earthquake', Measurement and location section (first-described sentence)
The first scale for measuring earthquake magnitudes was developed by Charles Francis Richter in 1935.
View the Source Reader Challenges (0)
No disputes yet. Spotted an error or a better source? Open the first one.
Sign in to dispute this or suggest a correction.