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Piendamó Fault
The Piendamó Fault ( es, Falla de Piendamó) is an oblique dextral strike-slip fault in the department of Cauca in southwestern Colombia. The fault is part of the megaregional Romeral Fault System and has a total length of and runs along a variable average north to south strike of 341.6 ± 18 in the Central Ranges of the Colombian Andes. Etymology The fault is named after Piendamó, Cauca.Paris et al., 2000a, p.23 Description The Piendamó Fault is part of Romeral Fault System in southwestern Colombia. The fault is located at the base of the mountain front of the western slope of the Central Ranges, north of the city of Popayán. The fault displaces volcanic pyroclastic deposits and mud flows of the Tertiary to Quaternary Popayán Formation. It forms an outstanding topographic and tectonic block bounded by two intersecting faults. The fault forms an outstanding prismatic-tectonic mountain block composed of pyroclastic flow and ash-fall deposits. This block is boun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piendamó, Cauca
Piendamó is a municipality in the departments of Colombia, department of Cauca Department, Cauca in southwestern Colombia. History The town of Piendamó was founded by Pedro Antonio Sandoval on April 2, 1525. Piendamó was formerly called Tunía and as such an encomienda of the list of conquistadors in Colombia, conquistadors Sebastian de Belalcázar, Francisco Arévalo, Pedro Matta and Pedro de Velasco y Martínez de Revilla, Pedro de Velasco. In 1917, the construction of the railway line that would link the city of Cali with the city of Popayán began, approving the layout for the site where Piendamó is today. At the beginning of 1924 the first locomotives arrived in this town and with them a large number of merchants, immigrants and settlers from the department of Valle del Cauca and the coffee region. Description The municipality is located in the Cauca Basin in the valley of the Cauca River at an altitude of above mean sea level. It borders Silvia, Cauca, Silvia in the ... [...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] |
Strike-slip Faults
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] |
Thrust Faults
A thrust fault is a break in the Earth's crust, across which older rocks are pushed above younger rocks. Thrust geometry and nomenclature Reverse faults A thrust fault is a type of reverse fault that has a dip of 45 degrees or less. If the angle of the fault plane is lower (often less than 15 degrees from the horizontal) and the displacement of the overlying block is large (often in the kilometer range) the fault is called an ''overthrust'' or ''overthrust fault''. Erosion can remove part of the overlying block, creating a ''fenster'' (or ''window'') – when the underlying block is exposed only in a relatively small area. When erosion removes most of the overlying block, leaving island-like remnants resting on the lower block, the remnants are called ''klippen'' (singular ''klippe''). Blind thrust faults If the fault plane terminates before it reaches the Earth's surface, it is referred to as a ''blind thrust'' fault. Because of the lack of surface evidence, blind thr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Seismic Faults Of Colombia
Seismology (; from Ancient Greek σεισμός (''seismós'') meaning " earthquake" and -λογία (''-logía'') meaning "study of") is the scientific study of earthquakes and the propagation of elastic waves through the Earth or through other planet-like bodies. It also includes studies of earthquake environmental effects such as tsunamis as well as diverse seismic sources such as volcanic, tectonic, glacial, fluvial, oceanic, atmospheric, and artificial processes such as explosions. A related field that uses geology to infer information regarding past earthquakes is paleoseismology. A recording of Earth motion as a function of time is called a seismogram. A seismologist is a scientist who does research in seismology. History Scholarly interest in earthquakes can be traced back to antiquity. Early speculations on the natural causes of earthquakes were included in the writings of Thales of Miletus (c. 585 BCE), Anaximenes of Miletus (c. 550 BCE), Aristotle (c. 340 ... [...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] |
Rosas-Julumito Fault
The Rosas-Julumito Fault ( es, Falla de Rosas-Julumito) is an oblique dextral strike-slip fault in the department of Cauca in southwestern Colombia. The fault is part of the megaregional Romeral Fault System and has a total length of and runs along an average northeast to southwest strike of 026.9 ± 7 in the Central Ranges of the Colombian Andes. The fault is associated with the 1983 Popayán earthquake that partially destroyed Popayán, the capital of Cauca, and led to more than 300 fatalities. A maximum moment magnitude earthquake of 6.8 is estimated for the fault. Etymology The fault is named after Rosas, Cauca and vereda Julumito of Popayán.Paris et al., 2000a, p.24 Description The Rosas-Julumito Fault is part of the Romeral Fault System. It is a rather short section of about length, of which have active tectonic movement. The fault section parallels the Cauca-Almaguer Fault, which is one of the largest older fracture zones in western Colombia. The Rosas-Julumi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Earthquakes In Colombia
This is a list of earthquakes in Colombia. Colombia is a seismically active country and has a large seismic risk in many areas of its territory due to its location at the boundaries of the Malpelo, Panama, Caribbean, North Andes (where most earthquakes occurred) and South American Plates along the Pacific Ring of Fire. The southeastern and extreme eastern portions of Colombia are not as seismically active as the rest of the country. The first historically registered earthquake felt in Colombia occurred on September 11, 1530, around 10:00 AM, probably with the epicentre near Cumaná, Venezuela. The earthquake was documented by Gonzalo Fernández de Oviedo y Valdés in his work ''La Historia general de las Indias'' and by friar Bartolomé de las Casas in his book ''Historia de Las Indias''.Ramírez, 1975, p.63 The first documented earthquake with its epicentre in present-day Colombia territory took place in 1566,Ramírez, 1975, p.65 with the epicentre estimated around Santander ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Landslide
Landslides, also known as landslips, are several forms of mass wasting that may include a wide range of ground movements, such as rockfalls, deep-seated grade (slope), slope failures, mudflows, and debris flows. Landslides occur in a variety of environments, characterized by either steep or gentle slope gradients, from mountain ranges to coastal cliffs or even underwater, in which case they are called submarine landslides. Gravity is the primary driving force for a landslide to occur, but there are other factors affecting slope stability that produce specific conditions that make a slope prone to failure. In many cases, the landslide is triggered by a specific event (such as a heavy rainfall, an earthquake, a slope cut to build a road, and many others), although this is not always identifiable. Causes Landslides occur when the slope (or a portion of it) undergoes some processes that change its condition from stable to unstable. This is essentially due to a decrease in the She ... [...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] |
Tertiary
Tertiary ( ) is a widely used but obsolete term for the geologic period from 66 million to 2.6 million years ago. The period began with the demise of the non-avian dinosaurs in the Cretaceous–Paleogene extinction event, at the start of the Cenozoic Era, and extended to the beginning of the Quaternary glaciation at the end of the Pliocene Epoch. The time span covered by the Tertiary has no exact equivalent in the current geologic time system, but it is essentially the merged Paleogene and Neogene periods, which are informally called the Early Tertiary and the Late Tertiary, respectively. The Tertiary established the Antarctic as an icy island continent. Historical use of the term The term Tertiary was first used by Giovanni Arduino during the mid-18th century. He classified geologic time into primitive (or primary), secondary, and tertiary periods based on observations of geology in Northern Italy. Later a fourth period, the Quaternary, was applied. In the early d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mud Flow
A mudflow or mud flow is a form of mass wasting involving fast-moving flow of debris that has become liquified by the addition of water. Such flows can move at speeds ranging from 3 meters/minute to 5 meters/second. Mudflows contain a significant proportion of clay, which makes them more fluid than debris flows, allowing them to travel farther and across lower slope angles. Both types of flow are generally mixtures of particles with a wide range of sizes, which typically become sorted by size upon deposition. Mudflows are often called mudslides, a term applied indiscriminately by the mass media to a variety of mass wasting events. Mudflows often start as slides, becoming flows as water is entrained along the flow path; such events are often called flow slides. Other types of mudflows include lahars (involving fine-grained pyroclastic deposits on the flanks of volcanoes) and jökulhlaups (outbursts from under glaciers or icecaps). A statutory definition of "flood-related mudsli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
