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1811–1812 New Madrid Earthquakes
The 1811–1812 New Madrid earthquakes () were a series of intense intraplate earthquakes beginning with an initial earthquake of moment magnitude 7.2–8.2 on December 16, 1811, followed by a moment magnitude 7.4 aftershock on the same day. Two additional earthquakes of similar magnitude followed in January and February 1812. They remain the most powerful earthquakes to hit the contiguous United States east of the Rocky Mountains in recorded history.Historic Earthquakes New Madrid Earthquakes 1811–1812 ''USGS'' The earthquakes, as well as the of their occurrence, were named for the [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Woodcut
Woodcut is a relief printing technique in printmaking. An artist carves an image into the surface of a block of wood—typically with gouges—leaving the printing parts level with the surface while removing the non-printing parts. Areas that the artist cuts away carry no ink, while characters or images at surface level carry the ink to produce the print. The block is cut along the wood grain (unlike wood engraving, where the block is cut in the end-grain). The surface is covered with ink by rolling over the surface with an ink-covered roller (brayer), leaving ink upon the flat surface but not in the non-printing areas. Multiple colors can be printed by keying the paper to a frame around the woodblocks (using a different block for each color). The art of carving the woodcut can be called "xylography", but this is rarely used in English for images alone, although that and "xylographic" are used in connection with block books, which are small books containing text and images in t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arkansas
Arkansas ( ) is a landlocked state in the South Central United States. It is bordered by Missouri to the north, Tennessee and Mississippi to the east, Louisiana to the south, and Texas and Oklahoma to the west. Its name is from the Osage language, a Dhegiha Siouan language, and referred to their relatives, the Quapaw people. The state's diverse geography ranges from the mountainous regions of the Ozark and Ouachita Mountains, which make up the U.S. Interior Highlands, to the densely forested land in the south known as the Arkansas Timberlands, to the eastern lowlands along the Mississippi River and the Arkansas Delta. Arkansas is the 29th largest by area and the 34th most populous state, with a population of just over 3 million at the 2020 census. The capital and most populous city is Little Rock, in the central part of the state, a hub for transportation, business, culture, and government. The northwestern corner of the state, including the Fayetteville–Springdaleâ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kentucky Bend
The Kentucky Bend, variously called the New Madrid Bend, Madrid Bend, Bessie Bend, or Bubbleland, is an exclave of Fulton County, Kentucky, encircled by the states of Tennessee and Missouri. It is a portion of a peninsula defined by an oxbow loop meander of the Mississippi River, and its inclusion in the state of Kentucky stems from uncertainties of the course of the Mississippi River when the boundary between Tennessee and Kentucky was established. Kentucky Bend is the extreme southwestern corner of Kentucky. The peninsula is traversed by the southern line of latitude of the state of Kentucky, at the banks of the Mississippi River. The only highway into the area is Tennessee State Route 22, whose continuation into Kentucky Bend at one time was signed as Kentucky State Route 313. As of the 2020 census, the population was 9 persons in this area, tabulated as the Kentucky Bend Census County Division. The mailing address of the area is Tiptonville, Tennessee. New Madrid, Missou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Waterfall
A waterfall is a point in a river or stream where water flows over a vertical drop or a series of steep drops. Waterfalls also occur where meltwater drops over the edge of a tabular iceberg or ice shelf. Waterfalls can be formed in several ways, but the most common method of formation is that a river courses over a top layer of resistant bedrock before falling on to softer rock, which Erosion, erodes faster, leading to an increasingly high fall. Waterfalls have been studied for their impact on species living in and around them. Humans have had a distinct relationship with waterfalls for years, travelling to see them, exploring and naming them. They can present formidable barriers to navigation along rivers. Waterfalls are religious sites in many cultures. Since the 18th century they have received increased attention as tourist destinations, sources of hydropower, andparticularly since the mid-20th centuryas subjects of research. Definition and terminology A waterfall is gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reverse Fault
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] |
Reelfoot Rift
The New Madrid Seismic Zone (), sometimes called the New Madrid Fault Line, is a major seismic zone and a prolific source of intraplate earthquakes (earthquakes within a tectonic plate) in the Southern and Midwestern United States, stretching to the southwest from New Madrid, Missouri. The New Madrid fault system was responsible for the 1811–12 New Madrid earthquakes, and has the potential to produce large earthquakes in the future. Since 1812, frequent smaller earthquakes have been recorded in the area. Earthquakes that occur in the New Madrid Seismic Zone potentially threaten parts of seven American states: Illinois, Indiana, Missouri, Arkansas, Kentucky, Tennessee, and Mississippi. Location The -long seismic zone, which extends into five states, stretches southward from Cairo, Illinois; through Hayti, Caruthersville, and New Madrid in Missouri; through Blytheville into Marked Tree in Arkansas. It also covers a part of West Tennessee, near Reelfoot Lake, extending south ... [...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] |
Meizoseismal Area
The meizoseismal area in an earthquake is the area of maximum damage. For example, in the Charleston, South Carolina, earthquake of 1886, the meizoseismal area was an area about twenty by thirty miles stretching northeast between Charleston and Jedburg and incorporating Summerville. The estimated epicenter was near Middleton Place Middleton Place is a plantation in Dorchester County, along the banks of the Ashley River west of the Ashley and about northwest of downtown Charleston, in the U.S. state of South Carolina. Built in several phases during the 18th and 19th cent .... References Seismology {{seismology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Missouri Bootheel
The Missouri Bootheel is a salient located in the southeasternmost part of the U.S. state of Missouri, extending south of 36°30′ north latitude, so called because its shape in relation to the rest of the state resembles the heel of a boot. Strictly speaking, it is composed of the counties of Dunklin, New Madrid, and Pemiscot. However, the term is locally used to refer to the entire southeastern lowlands of Missouri located within the Mississippi Embayment, which includes parts of Butler, Mississippi, Ripley, Scott, Stoddard and extreme southern portions of Cape Girardeau and Bollinger counties. The largest city in the region is Kennett. Until the 1920s, the district was a wheat-growing area of family farms. Following the invasion of the boll weevil, which ruined the cotton crop in Arkansas, planters moved in. They bought up the land for conversion to cotton commodity crops, bringing along thousands of sharecroppers. After mechanization of agriculture and other chan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soil Liquefaction
Soil liquefaction occurs when a cohesionless saturated or partially saturated soil substantially loses strength and stiffness in response to an applied stress such as shaking during an earthquake or other sudden change in stress condition, in which material that is ordinarily a solid behaves like a liquid. In soil mechanics, the term "liquefied" was first used by Allen Hazen in reference to the 1918 failure of the Calaveras Dam in California. He described the mechanism of flow liquefaction of the embankment dam as: The phenomenon is most often observed in saturated, loose (low density or uncompacted), sandy soils. This is because a loose sand has a tendency to compress when a load is applied. Dense sands, by contrast, tend to expand in volume or 'dilate'. If the soil is saturated by water, a condition that often exists when the soil is below the water table or sea level, then water fills the gaps between soil grains ('pore spaces'). In response to soil compressing, the po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caruthersville, Missouri
Caruthersville is a city in and the county seat of Pemiscot County, Missouri, United States, located along the Mississippi River in the Bootheel region of the state's far southeast. The population was 5,562, according to the 2020 census. History Caruthersville lies in Missouri's Bootheel on the Mississippi River. The word "Pemiscot" comes from the word meaning "liquid mud" in the Fox language. Mississippi waters have frequently flooded the flatlands, creating fertile alluvial land valued for farming. Settling the floodplain has resulted in periodic problems for residents, as there are regular floods despite (and because of) elaborate constructed systems of levees and flood controls. Native Americans inhabited the land of the Caruthersville area for thousands of years before European settlement. The Mississippian culture built huge earthwork mounds throughout the Mississippi Valley. One such earthwork remains in this county, rising 270 feet above sea level about four miles s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fort San Fernando De Las Barrancas
Fort San Fernando De Las Barrancas was a Spanish fort in what is now Memphis, Tennessee. Established in May 1795, the fort was erected with a garrison of 150 men to defend Spain, Spanish claims of the territory at the Chickasaw Bluff, Fourth Chickasaw Bluff. Although Spain renounced its claim to the area in Pinckney's Treaty in 1795, it occupied the fort until either 1797 or 1798, when the Spanish dismantled the fort and established Fort Esperanza across the river near modern Marion, Arkansas. References {{coord missing, Tennessee Colonial forts in Tennessee Memphis, Tennessee Spanish forts in the United States ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
