Search results
Results From The WOW.Com Content Network
Also called Indianite. A mineral from the lime-rich end of the plagioclase group of minerals. Anorthites are usually silicates of calcium and aluminium occurring in some basic igneous rocks, typically those produced by the contact metamorphism of impure calcareous sediments. anticline An arched fold in which the layers usually dip away from the fold axis. Contrast syncline. aphanic Having the ...
As an example, in the magnitude 7.9 Denali earthquake of 2002 in Alaska, the epicenter was at the western end of the rupture, but the greatest damage was about 330 km (210 mi) away at the eastern end. [7] Focal depths of earthquakes occurring in continental crust mostly range from 2 to 20 kilometers (1.2 to 12.4 mi). [8]
The epicenter, or epicentre, is the point on the Earth's surface that is directly above the point where an earthquake or underground explosion originates. Epicenter or epicentre may also refer to: Blast seat, the point of detonation of an explosive device; Epicenter, a 2006 book by Joel C. Rosenberg
Map showing Earth's principal tectonic plates and their boundaries in detail. These plates comprise the bulk of the continents and the Pacific Ocean.For purposes of this list, a major plate is any plate with an area greater than 20 million km 2 (7.7 million sq mi)
Hypocenter (Focus) and epicenter of an earthquake. An earthquake's hypocenter or focus is the position where the strain energy stored in the rock is first released, marking the point where the fault begins to rupture. [3] This occurs directly beneath the epicenter, at a distance known as the hypocentral depth or focal depth. [3]
In its most general sense, the word earthquake is used to describe any seismic event that generates seismic waves. Earthquakes can occur naturally or be induced by human activities, such as mining, fracking, and nuclear tests. The initial point of rupture is called the hypocenter or focus, while the ground level directly above it is the epicenter.
Even if the depth of focus of an earthquake is very deep, it can still have a very short epicentral distance. [3] When measuring the epicentral distance of an earthquake with a small epicentral distance, first measure the reading of the initial motion of P wave, and then confirm the arrival of S wave.
It's the other way round: epicentre (or focus) = where the bomb goes off, hypocentre = point on ground vertically beneath epicentre. Astronaut 23:23, 10 August 2007 (UTC) [ reply ] If "The epicenter or epicentre is the point on the Earth's surface that is directly above the hypocenter or focus" we need a (straight) line to follow in order to ...