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1973 Ragay Gulf Earthquake
The 1973 Ragay Gulf earthquake occurred at around 16:30 local time (UTC +8). It was measured as magnitude 7.4 Mw on the moment magnitude scale. It had a maximum intensity of IX (''Violent'') on the MMI, according to the National Geophysics Data Center, while according to the Philippine Institute of Volcanology and Seismology, the tremor had an intensity of VIII (''Very Destructive'') on the PHIVOLCS Earthquake Intensity Scale. It killed 14 people, injured 100 others, and caused an estimated $2 million in damages. Earthquake The epicenter was located around 17 km east northeast of San Andres on the Ragay Gulf with a depth of 33 km (20.5 mi). It was due to the movement of one of the Philippines' largest fault; the Philippine Fault System with the focal mechanism corresponding to strike-slip. Surface rupture and fissures The earthquake produced an onshore surface rupture 30 km along the Guinayangan segment of the Philippine Fault. It also caused left-lat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fault (geology)
In geology, a fault is a planar fracture or discontinuity in a volume of rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust result from the action of plate tectonic forces, with the largest forming the boundaries between the plates, such as the megathrust faults of subduction zones or transform faults. Energy release associated with rapid movement on active faults is the cause of most earthquakes. Faults may also displace slowly, by aseismic creep. A ''fault plane'' is the plane that represents the fracture surface of a fault. A ''fault trace'' or ''fault line'' is a place where the fault can be seen or mapped on the surface. A fault trace is also the line commonly plotted on geologic maps to represent a fault. A ''fault zone'' is a cluster of parallel faults. However, the term is also used for the zone of crushed rock along a single fault. Prolonged motion along closely spaced faults can blur the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
