Search results
Results From The WOW.Com Content Network
Earthquakes. The epicenter ( / ˈɛpɪˌsɛntər / ), epicentre, or epicentrum [1] in seismology is the point on the Earth 's surface directly above a hypocenter or focus, the point where an earthquake or an underground explosion originates.
In seismology, an isoseismal map is used to show lines of equally felt seismic intensity, generally measured on the Modified Mercalli scale. Such maps help to identify earthquake epicenters, particularly where no instrumental records exist, such as for historical earthquakes. They also contain important information on ground conditions at ...
e. Epicentral distance refers to the ground distance from the epicenter to a specified point. [1] Generally, the smaller the epicentral distance of an earthquake of the same scale, the heavier the damage caused by the earthquake. On the contrary, with the increase of epicentral distance, the damage caused by the earthquake is gradually reduced. [2]
Earthquake-resistant or aseismic structures are designed to protect buildings to some or greater extent from earthquakes. While no structure can be entirely impervious to earthquake damage, the goal of earthquake engineering is to erect structures that fare better during seismic activity than their conventional counterparts.
The Modified Mercalli intensity scale ( MM, MMI, or MCS) measures the effects of an earthquake at a given location. This is in contrast with the seismic magnitude usually reported for an earthquake. Magnitude scales measure the inherent force or strength of an earthquake – an event occurring at greater or lesser depth.
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]
Earthquake casualty estimation. Recent advances are improving the speed and accuracy of loss estimates immediately after earthquakes (within less than an hour) so that injured people may be rescued more efficiently. "Casualties" are defined as fatalities and injured people, which are due to damage to occupied buildings.
Deferent and epicycle. The epicycles of the planets in orbit around Earth (Earth at the center). The path-line is the combined motion of the planet's orbit (deferent) around Earth and within the orbit itself (epicycle). In the Hipparchian, Ptolemaic, and Copernican systems of astronomy, the epicycle (from Ancient Greek ἐπίκυκλος ...