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Córdoba-Navarco Fault
The Córdoba-Navarco Fault ( es, Falla Córdoba-Navarco) is a sinistral strike-slip fault in the department of Quindío in west-central Colombia. The fault has a total length of and runs along an average north-northeast to south-southwest strike of 018.5 ± 4 in the Central Ranges of the Colombian Andes. The fault segment pertaining to the megaregional Romeral Fault System is a set of two faults that are active, causing the major 1999 Armenia earthquake with approximately 1185 fatalities. Etymology The fault is named after Córdoba and the Navarco River in Quindío.Paris et al., 2000a, p.25 Description The fault section is formed by the Córdoba and Navarco Faults, which are eastern strands of Romeral Fault System, south of the city of Armenia. These faults lie within the epicenter area of the Armenia earthquake of January 25, 1999. The faults extend through sheared cataclastic and undeformed basaltic and sedimentary Cretaceous oceanic rocks, cropping out on the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Córdoba, Quindío
Córdoba is a municipality in the eastern part of the department of Quindío, Colombia. It is located 24 km southeast of the departmental capital Armenia. Córdoba is bounded to the north by the municipality of Calarcá, to the south by Pijao, to the west by Buenavista, and to the east by the department of Tolima. Córdoba was founded in 1927 by Jesús García and Jesús Buitrago, and became a municipality in 1966 when it split from Calarcá. In 2005 it had an estimated population of 7,800, of which 4,100 live in the main urban zone. By population it is the second smallest municipality in Quindío, after Buenavista. Córdoba is home to the National Bamboo and Guadua Investigation Center (). Open to the public, the center shows the potential uses of guadua ''Guadua'' is a Neotropical genus of thorny, clumping bamboo in the grass family, ranging from moderate to very large species. Physically, ''Guadua angustifolia'' is noted for being the largest Neotropical ba ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strike (geology)
Strike and dip is a measurement convention used to describe the orientation, or attitude, of a planar geologic feature. A feature's strike is the azimuth of an imagined horizontal line across the plane, and its dip is the angle of inclination measured downward from horizontal. They are used together to measure and document a structure's characteristics for study or for use on a geologic map. A feature's orientation can also be represented by dip and dip direction, using the azimuth of the dip rather than the strike value. Linear features are similarly measured with trend and plunge, where "trend" is analogous to dip direction and "plunge" is the dip angle. Strike and dip are measured using a compass and a clinometer. A compass is used to measure the feature's strike by holding the compass horizontally against the feature. A clinometer measures the features dip by recording the inclination perpendicular to the strike. These can be done separately, or together using a tool such a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States Geological Survey
The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, and the natural hazards that threaten it. The organization's work spans the disciplines of biology, geography, geology, and hydrology. The USGS is a fact-finding research organization with no regulatory responsibility. The agency was founded on March 3, 1879. The USGS is a bureau of the United States Department of the Interior; it is that department's sole scientific agency. The USGS employs approximately 8,670 people and is headquartered in Reston, Virginia. The USGS also has major offices near Lakewood, Colorado, at the Denver Federal Center, and Menlo Park, California. The current motto of the USGS, in use since August 1997, is "science for a changing world". The agency's previous slogan, adopted on the occasion of its hundredt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercalli Intensity Scale
The Modified Mercalli intensity scale (MM, MMI, or MCS), developed from Giuseppe Mercalli's Mercalli intensity scale of 1902, is a seismic intensity scale used for measuring the intensity of shaking produced by an earthquake. It measures the effects of an earthquake at a given location, distinguished from the earthquake's inherent force or strength as measured by seismic magnitude scales (such as the "" magnitude usually reported for an earthquake). While shaking is caused by the seismic energy released by an earthquake, earthquakes differ in how much of their energy is radiated as seismic waves. Deeper earthquakes also have less interaction with the surface, and their energy is spread out across a larger volume. Shaking intensity is localized, generally diminishing with distance from the earthquake's epicenter, but can be amplified in sedimentary basins and certain kinds of unconsolidated soils. Intensity scales empirically categorize the intensity of shaking based on the effect ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moment Magnitude Scale
The moment magnitude scale (MMS; denoted explicitly with or Mw, and generally implied with use of a single M for magnitude) is a measure of an earthquake's magnitude ("size" or strength) based on its seismic moment. It was defined in a 1979 paper by Thomas C. Hanks and Hiroo Kanamori. Similar to the local magnitude scale, local magnitude/Richter scale () defined by Charles Francis Richter in 1935, it uses a logarithmic scale; small earthquakes have approximately the same magnitudes on both scales. Despite the difference, news media often says "Richter scale" when referring to the moment magnitude scale. Moment magnitude () is considered the authoritative magnitude scale for ranking earthquakes by size. It is more directly related to the energy of an earthquake than other scales, and does not saturate—that is, it does not underestimate magnitudes as other scales do in certain conditions. It has become the standard scale used by seismological authorities like the U.S. Geological ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pereira, Colombia
Pereira () is the capital city of the Colombian department of Risaralda. It is located in the foothills of the Andes in a coffee-producing area of Colombia officially known as the " Coffee Axis". Pereira, alongside the rest of the Coffee Axis, form part of UNESCO World Heritage Site known as the "Coffee Cultural Landscape of Colombia"."Colombia green guide Michelin 2012-2013." Michelin. 2012. Accessed at Google Books 29 December 2013. It is the most populated city in the Coffee Axis. Pereira is also part of the Central West Metropolitan Area, which has 709,322 residents and is composed of Pereira and the neighboring cities of Dosquebradas and |
Risaralda Department
Risaralda () or "Rizaralde", is a landlocked department of Colombia. It is located in the western central region of the country and part of the Paisa Region. Its capital is Pereira. It was divided from the department of Caldas in 1966. Risaralda is very well known for the high quality of its coffee, and a booming industry: clothes, food, trading of goods and services. The territory is very mountainous and has many kinds of climates in a very small area. Its proximity to harbours such as Goodventure on the Pacific Ocean and to the biggest cities in Colombia – Bogota, Cali, Medellin – makes it a fast-growing economic centre. Geography Risaralda department with an area of , is located in the central sector of the central Andean region west of the country between two major poles of economic development (department of Antioquia in northern and southern Cauca Valley, extending between the central and western Cordillera), which slopes down toward the Río Cauca, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ibagué Fault
The Ibagué Fault ( es, Falla de Ibagué) is a major dextral slightly thrust fault, oblique strike-slip fault in the departments of Colombia, department of Tolima Department, Tolima in central Colombia. The fault has a total length of and runs along an average east-northeast to west-southwest strike (geology), strike of 067.9 ± 11 cross-cutting the Cordillera Central (Colombia), Central Ranges of the Colombian Andes. The fault is part of a regional shear zone and has been active in historical times, possibly associated with the 1825 Ibagué earthquake and an earthquake in 1942. Etymology The fault is named after Ibagué, the capital of Tolima Department, Tolima.Diederix et al., 2006, p.492 Description The Ibagué Fault crosses the central part and eastern slope of the Cordillera Central (Colombia), Central Ranges of the Colombian Andes, close to the city of Ibagué. The fault strikes west-southwest to east-northeast, controlling the course of the Cocora Valley, Cocora Rive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fault Scarp
A fault scarp is a small step or offset on the ground surface where one side of a fault has moved vertically with respect to the other. It is the topographic expression of faulting attributed to the displacement of the land surface by movement along faults. They are exhibited either by differential movement and subsequent erosion along an old ''inactive'' geologic fault (a sort of old rupture), or by a movement on a recent active fault. Characteristics Fault scarps often contain highly fractured rock of both hard and weak consistency. In many cases, bluffs form from the upthrown block and can be very steep. The height of the scarp formation is equal to the vertical displacement along the fault. Active scarps are usually formed by tectonic displacement, e.g. when an earthquake changes the elevation of the ground and can be caused by any type of fault, including strike-slip faults, whose motion is primarily horizontal. This movement is usually episodic, with the height of the bluf ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oceanic Crust
Oceanic crust is the uppermost layer of the oceanic portion of the tectonic plates. It is composed of the upper oceanic crust, with pillow lavas and a dike complex, and the lower oceanic crust, composed of troctolite, gabbro and ultramafic cumulates. The crust overlies the rigid uppermost layer of the mantle. The crust and the rigid upper mantle layer together constitute oceanic lithosphere. Oceanic crust is primarily composed of mafic rocks, or sima, which is rich in iron and magnesium. It is thinner than continental crust, or sial, generally less than 10 kilometers thick; however, it is denser, having a mean density of about 3.0 grams per cubic centimeter as opposed to continental crust which has a density of about 2.7 grams per cubic centimeter. The crust uppermost is the result of the cooling of magma derived from mantle material below the plate. The magma is injected into the spreading center, which consists mainly of a partly solidified crystal mush derived from earlier ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin ''creta'', "chalk", which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation ''Kreide''. The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now- extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Earth b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basalt
Basalt (; ) is an aphanite, aphanitic (fine-grained) extrusive igneous rock formed from the rapid cooling of low-viscosity lava rich in magnesium and iron (mafic lava) exposed at or very near the planetary surface, surface of a terrestrial planet, rocky planet or natural satellite, moon. More than 90% of all volcanic rock on Earth is basalt. Rapid-cooling, fine-grained basalt is chemically equivalent to slow-cooling, coarse-grained gabbro. The eruption of basalt lava is observed by geologists at about 20 volcanoes per year. Basalt is also an important rock type on other planetary bodies in the Solar System. For example, the bulk of the plains of volcanism on Venus, Venus, which cover ~80% of the surface, are basaltic; the lunar mare, lunar maria are plains of flood-basaltic lava flows; and basalt is a common rock on the surface of Mars. Molten basalt lava has a low viscosity due to its relatively low silica content (between 45% and 52%), resulting in rapidly moving lava flo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
