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1973 Colima Earthquake
On January 30, 1973, at 15:01 ( UTC–6), a magnitude 7.6 earthquake struck beneath the Sierra Madre del Sur range in the Mexican states of Colima, Jalisco and Michoacán. On the Mercalli intensity scale, the earthquake reached a maximum intensity of X (''Extreme''), causing serious damage in the region. At least 56 people were killed and about 390 were injured. The event is commonly referred to as the Colima earthquake. Tectonic setting Off the west coast of Mexico is the Middle America Trench; a convergent plate boundary where the Cocos and Rivera plates subducts beneath the North American Plate at a rate of ~6-9 cm/yr. The interface of this plate boundary is a huge thrust fault known as a megathrust which occasionally produces large megathrust earthquakes and tsunamis. Earthquake The January 30 earthquake ruptured a shallow-angle section of the megathrust near a triple junction with the Rivera Plate. Its location places it very close to the rupture patch of the 1941 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Central Time Zone
The North American Central Time Zone (CT) is a time zone in parts of Canada, the United States, Mexico, Central America, some Caribbean Islands, and part of the Eastern Pacific Ocean. Central Standard Time (CST) is six hours behind Coordinated Universal Time (UTC). During summer, most of the zone uses daylight saving time (DST), and changes to Central Daylight Time (CDT) which is five hours behind UTC. The largest city in the Central Time Zone is Mexico City; the Mexico City metropolitan area is the largest metropolitan area in the zone and in North America. Regions using (North American) Central Time Canada The province of Manitoba is the only province or territory in Canada that observes Central Time in all areas. The following Canadian provinces and territories observe Central Time in the areas noted, while their other areas observe Eastern Time: * Nunavut (territory): western areas (most of Kivalliq Region and part of Qikiqtaaluk Region) * Ontario (province): a port ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
North American Plate
The North American Plate is a tectonic plate covering most of North America, Cuba, the Bahamas, extreme northeastern Asia, and parts of Iceland and the Azores. With an area of , it is the Earth's second largest tectonic plate, behind the Pacific Plate (which borders the plate to the west). It extends eastward to the Mid-Atlantic Ridge and westward to the Chersky Range in eastern Siberia. The plate includes both continental and oceanic crust. The interior of the main continental landmass includes an extensive granitic core called a craton. Along most of the edges of this craton are fragments of crustal material called terranes, which are accreted to the craton by tectonic actions over a long span of time. It is thought that much of North America west of the Rocky Mountains is composed of such terranes. Boundaries The southern boundary with the Cocos Plate to the west and the Caribbean Plate to the east is a transform fault, represented by the Swan Islands Transform Fault unde ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tecomán
Tecomán is a city and seat of the municipality of Tecomán in the Mexican state of Colima Colima (), officially the Free and Sovereign State of Colima ( es, Estado Libre y Soberano de Colima), is one of the 31 states that make up the 32 Federal Entities of Mexico. It shares its name with its capital and main city, Colima. Colima i ..., about 50 km south of the city of Colima. In the 2005 census the city had a population of 112,726 people. It is the third-largest community in the state of Colima. The municipality has an area of 834.77 km² (322.31 sq mi). Near the coast on Federal Highway 200, it is situated a rich agricultural industries region and is known as the "lime capital of the world". Due to its soaring homicide rate, Tecomán became the deadliest municipality in Mexico in 2016. Economy The main economic activities of the area are: * Agriculture: Limes, coconuts, tamarind, mango and bananas. * Livestock: Cattle, pigs, sheep, goats and apiculture. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gulf Of Mexico
The Gulf of Mexico ( es, Golfo de México) is an oceanic basin, ocean basin and a marginal sea of the Atlantic Ocean, largely surrounded by the North American continent. It is bounded on the northeast, north and northwest by the Gulf Coast of the United States; on the southwest and south by the Mexico, Mexican States of Mexico, states of Tamaulipas, Veracruz, Tabasco, Campeche, Yucatan, and Quintana Roo; and on the southeast by Cuba. The Southern United States, Southern U.S. states of Texas, Louisiana, Mississippi, Alabama, and Florida, which border the Gulf on the north, are often referred to as the "Third Coast" of the United States (in addition to its Atlantic and Pacific Ocean, Pacific coasts). The Gulf of Mexico took shape approximately 300 million years ago as a result of plate tectonics.Huerta, A.D., and D.L. Harry (2012) ''Wilson cycles, tectonic inheritance, and rifting of the North American Gulf of Mexico continental margin.'' Geosphere. 8(1):GES00725.1, first p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hawaii
Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only state geographically located within the tropics. Hawaii comprises nearly the entire Hawaiian archipelago, 137 volcanic islands spanning that are physiographically and ethnologically part of the Polynesian subregion of Oceania. The state's ocean coastline is consequently the fourth-longest in the U.S., at about . The eight main islands, from northwest to southeast, are Niihau, Kauai, Oahu, Molokai, Lānai, Kahoolawe, Maui, and Hawaii—the last of these, after which the state is named, is often called the "Big Island" or "Hawaii Island" to avoid confusion with the state or archipelago. The uninhabited Northwestern Hawaiian Islands make up most of the Papahānaumokuākea Marine National Monument, the United States' largest protected ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tide Gauge
A tide gauge is a device for measuring the change in sea level relative to a vertical datum. It its also known as mareograph, marigraph, sea-level recorder and limnimeter. When applied to freshwater continental water bodies, the instrument may also be called a limnimeter. Operation Sensors continuously record the height of the water level with respect to a height reference surface close to the geoid. Water enters the device by the bottom pipe (far end of the tube, see picture), and electronic sensors measure its height and send the data to a tiny computer. Historical data are available for about 1,450 stations worldwide, of which about 950 have provided updates to the global data center since January 2010. At some places records cover centuries, for example in Amsterdam where data dating back to 1700 is available. When it comes to estimating the greater ocean picture, new modern tide gauges can often be improved upon by using satellite data. Tide gauges are used to measure ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seismograph
A seismometer is an instrument that responds to ground noises and shaking such as caused by earthquakes, volcanic eruptions, and explosions. They are usually combined with a timing device and a recording device to form a seismograph. The output of such a device—formerly recorded on paper (see picture) or film, now recorded and processed digitally—is a seismogram. Such data is used to locate and characterize earthquakes, and to study the Earth's internal structure. Basic principles A simple seismometer, sensitive to up-down motions of the Earth, is like a weight hanging from a spring, both suspended from a frame that moves along with any motion detected. The relative motion between the weight (called the mass) and the frame provides a measurement of the vertical ground motion. A rotating drum is attached to the frame and a pen is attached to the weight, thus recording any ground motion in a seismogram. Any movement from the ground moves the frame. The mass tends not to m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aftershock
In seismology, an aftershock is a smaller earthquake that follows a larger earthquake, in the same area of the main shock, caused as the displaced crust adjusts to the effects of the main shock. Large earthquakes can have hundreds to thousands of instrumentally detectable aftershocks, which steadily decrease in magnitude and frequency according to a consistent pattern. In some earthquakes the main rupture happens in two or more steps, resulting in multiple main shocks. These are known as doublet earthquakes, and in general can be distinguished from aftershocks in having similar magnitudes and nearly identical seismic waveforms. Distribution of aftershocks Most aftershocks are located over the full area of fault rupture and either occur along the fault plane itself or along other faults within the volume affected by the strain associated with the main shock. Typically, aftershocks are found up to a distance equal to the rupture length away from the fault plane. The pattern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seismic Gap
A seismic gap is a segment of an active fault known to produce significant earthquakes that has not slipped in an unusually long time, compared with other segments along the same structure. There is a hypothesis or theory that states that over long periods of time, the displacement on any segment must be equal to that experienced by all the other parts of the fault. Any large and longstanding gap is, therefore, considered to be the fault segment most likely to suffer future earthquakes. The applicability of this approach has been criticised by some seismologists although earthquakes sometimes have occurred in previously-identified seismic gaps. Examples Loma Prieta Seismic Gap, California Prior to the 1989 Loma Prieta earthquake( = 6.9), that segment of the San Andreas fault system recorded much less seismic activity than other parts of the fault. The main shock and aftershocks of the 1989 event occurred within the previous seismic gap. Central Kuril gap, Russia Immediately foll ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1941 Colima Earthquake
The 1941 Colima earthquake occurred on April 15 at 19:09 UTC (13:09 local time). The epicenter was located in the State of Michoacán, Mexico. The magnitude of this earthquake was put at Ms 7.7 or Mw 7.7. The intensities were X (''Extreme'') in Colima, VIII (''Severe'') in Manzanillo, and V (''Moderate'') in Mexico City. Ninety people were reported dead. The cathedral of Colima was destroyed. Many houses and public buildings in Colima, including the Federal Palace (Palacio federal) and the Hidalgo Theater (Teatro Hidalgo), were damaged. Of the 8,000 houses in the city of Colima, 900 or 2000 collapsed, according to different sources. This earthquake was an interplate earthquake between the Cocos Plate and the North American Plate. It occurred in the Colima region of the Middle America Trench. This earthquake was very close to where the 1973 Colima earthquake occurred. From the locally recorded time intervals between the arrival of the S wave and the P wave (S−P times) and f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triple Junction
A triple junction is the point where the boundaries of three tectonic plates meet. At the triple junction each of the three boundaries will be one of three types – a ridge (R), trench (T) or transform fault (F) – and triple junctions can be described according to the types of plate margin that meet at them (e.g. Fault-Fault-Trench, Ridge-Ridge-Ridge, or abbreviated F-F-T, R-R-R). Of the ten possible types of triple junction only a few are stable through time ('stable' in this context means that the geometrical configuration of the triple junction will not change through geologic time). The meeting of four or more plates is also theoretically possible but junctions will only exist instantaneously. History The first scientific paper detailing the triple junction concept was published in 1969 by Dan McKenzie and W. Jason Morgan. The term had traditionally been used for the intersection of three divergent boundaries or spreading ridges. These three divergent boundaries ideally ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earthquake Rupture
In seismology, an earthquake rupture is the extent of slip that occurs during an earthquake in the Earth's crust. Earthquakes occur for many reasons that include: landslides, movement of magma in a volcano, the formation of a new fault, or, most commonly of all, a slip on an existing fault. Nucleation A tectonic earthquake begins by an initial rupture at a point on the fault surface, a process known as nucleation. The scale of the nucleation zone is uncertain, with some evidence, such as the rupture dimensions of the smallest earthquakes, suggesting that it is smaller than 100 m while other evidence, such as a slow component revealed by low-frequency spectra of some earthquakes, suggest that it is larger. The possibility that the nucleation involves some sort of preparation process is supported by the observation that about 40% of earthquakes are preceded by foreshocks. However, some large earthquakes, such as the M8.6 1950 India - China earthquake., have no foreshocks and it re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
