Search results
Results From The WOW.Com Content Network
Seismic intensity scales categorize the intensity or severity of ground shaking (quaking) at a given location, such as resulting from an earthquake.They are distinguished from seismic magnitude scales, which measure the magnitude or overall strength of an earthquake, which may, or perhaps may not, cause perceptible shaking.
In other words, the earthquake zoning map of India divides India into 4 seismic zones (Zone 2, 3, 4 and 5) unlike its previous version, which consisted of five or six zones for the country. According to the present zoning map, Zone 5 expects the highest level of seismicity whereas Zone 2 is associated with the lowest level of seismicity.
Isoseismal map for the 1968 Illinois earthquake. The irregular distribution of shaking arises from variations of geology and ground conditions. The Earth's crust is stressed by tectonic forces. When this stress becomes great enough to rupture the crust, or to overcome the friction that prevents one block of crust from slipping past another ...
A type of seismic zone is a Wadati–Benioff zone which corresponds with the down-going slab in a subduction zone. [2] The world's greatest seismic belt, known as the Circum-Pacific seismic belt, [3] is where a majority of the Earth's quakes occur. Approximately 81% of major earthquakes occur along this belt.
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
The effects of any one earthquake can vary greatly from place to place, so many MMI values may be measured for the same earthquake. These values can be displayed best using a contoured map of equal intensity, known as an isoseismal map. However, each earthquake has only one magnitude.
It is often used within earthquake engineering (including seismic building codes) and it is commonly plotted on seismic hazard maps. [6] In an earthquake, damage to buildings and infrastructure is related more closely to ground motion, of which PGA is a measure, rather than the magnitude of the earthquake itself.
The U.S. Geological Survey (USGS) reported that a magnitude 5.8 M w earthquake hit Virginia on Tuesday, August 23, 2011, at 17:51:04 UTC (1:51 pm Eastern Daylight Time). The quake occurred at an approximate depth of 3.7 miles and was centered in Louisa County (location at 37.936°N, 77.933°W), 5 miles SSW of Mineral, Virginia and 37 miles NW of Richmond, Virginia's capital. [3]