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Submarine Landslide
Submarine landslides are marine landslides that transport sediment across the continental shelf and into the deep ocean. A submarine landslide is initiated when the downwards driving stress (gravity and other factors) exceeds the resisting stress of the seafloor slope material, causing movements along one or more concave to planar rupture surfaces. Submarine landslides take place in a variety of different settings, including planes as low as 1°, and can cause significant damage to both life and property. Recent advances have been made in understanding the nature and processes of submarine landslides through the use of sidescan sonar and other seafloor mapping technology.Hampton, M & Locat, J (1996) Submarine landslides. Reviews of Geophysics, 34, 33–59.Locat, J & Lee, HJ (2002) Submarine landslides: Advances and challenges. Canadian Geotechnical Journal, 39, 193.Mason, D, Habitz, C, Wynn, R, Pederson, G & Lovholt, F (2006) Submarine landslides: processes, triggers and hazar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multibeam Echosounder
A multibeam echosounder (MBES) is a type of sonar that is used to map the seabed. It emits acoustic waves in a fan shape beneath its transceiver. The time it takes for the sound waves to reflect off the seabed and return to the receiver is used to calculate the water depth. Unlike other sonars and echo sounders, MBES uses beamforming to extract directional information from the returning soundwaves, producing a swath of depth soundings from a single ping. History and progression Multibeam sonar sounding systems, also known as ''swathe'' (British English) or ''swath'' (American English), originated for military applications. The Sonar Array Sounding System (SASS) was developed in the early 1960s by the US Navy, in conjunction with General Instrument to map large swaths of the ocean floor to assist the underwater navigation of its submarine force. SASS was tested aboard the USS ''Compass Island'' (AG-153). The final array system, composed of sixty-one one degree beams with a swa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Natural Gas
Natural gas (also called fossil gas or simply gas) is a naturally occurring mixture of gaseous hydrocarbons consisting primarily of methane in addition to various smaller amounts of other higher alkanes. Low levels of trace gases like carbon dioxide, nitrogen, hydrogen sulfide, and helium are also usually present. Natural gas is colorless and odorless, so odorizers such as mercaptan (which smells like sulfur or rotten eggs) are commonly added to natural gas supplies for safety so that leaks can be readily detected. Natural gas is a fossil fuel and non-renewable resource that is formed when layers of organic matter (primarily marine microorganisms) decompose under anaerobic conditions and are subjected to intense heat and pressure underground over millions of years. The energy that the decayed organisms originally obtained from the sun via photosynthesis is stored as chemical energy within the molecules of methane and other hydrocarbons. Natural gas can be burned fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hurricane Camille
Hurricane Camille was the second most intense tropical cyclone on record to strike the United States, behind the 1935 Labor Day hurricane. The most intense storm of the 1969 Atlantic hurricane season, Camille originated as a tropical depression on August 14, south of Cuba, from a long-tracked tropical wave. Located in a favorable environment for strengthening, the storm quickly intensified into a Category 2 hurricane before striking the western part of Cuba on August 15. Emerging into the Gulf of Mexico, Camille underwent another period of rapid intensification and became a Category 5 hurricane the next day as it moved northward towards the Louisiana–Mississippi region. Despite weakening slightly on August 17, the hurricane quickly re-intensified back into a Category 5 hurricane before it made landfall a half-hour before midnight in Bay St. Louis, Mississippi. At peak intensity, the hurricane had peak 1-minute sustained winds of 175 mph (280 km/h) and a mi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hurricane
A tropical cyclone is a rapidly rotating storm system characterized by a low-pressure center, a closed low-level atmospheric circulation, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain and squalls. Depending on its location and strength, a tropical cyclone is referred to by different names, including hurricane (), typhoon (), tropical storm, cyclonic storm, tropical depression, or simply cyclone. A hurricane is a strong tropical cyclone that occurs in the Atlantic Ocean or northeastern Pacific Ocean, and a typhoon occurs in the northwestern Pacific Ocean. In the Indian Ocean, South Pacific, or (rarely) South Atlantic, comparable storms are referred to simply as "tropical cyclones", and such storms in the Indian Ocean can also be called "severe cyclonic storms". "Tropical" refers to the geographical origin of these systems, which form almost exclusively over tropical seas. "Cyclone" refers to their winds moving in a circle, whirling round ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Grand Banks
The Grand Banks of Newfoundland are a series of underwater plateaus south-east of the island of Newfoundland on the North American continental shelf. The Grand Banks are one of the world's richest fishing grounds, supporting Atlantic cod, swordfish, haddock and capelin, as well as shellfish, seabirds and sea mammals. Significance The Grand Banks of Newfoundland are a group of underwater plateaus south-east of Newfoundland on the North American continental shelf. These areas are relatively shallow, ranging from in depth. The cold Labrador Current mixes with the warm waters of the Gulf Stream here, often causing extreme foggy conditions. The mixing of these waters and the shape of the ocean bottom lifts nutrients to the surface. These conditions helped to create one of the richest fishing grounds in the world. Fish species include Atlantic cod, swordfish, haddock and capelin; shellfish include scallop and lobster. The area also supports large colonies of seabirds such as north ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earthquake
An earthquake (also known as a quake, tremor or temblor) is the shaking of the surface of the Earth resulting from a sudden release of energy in the Earth's lithosphere that creates seismic waves. Earthquakes can range in intensity, from those that are so weak that they cannot be felt, to those violent enough to propel objects and people into the air, damage critical infrastructure, and wreak destruction across entire cities. The seismic activity of an area is the frequency, type, and size of earthquakes experienced over a particular time period. The seismicity at a particular location in the Earth is the average rate of seismic energy release per unit volume. The word ''tremor'' is also used for Episodic tremor and slip, non-earthquake seismic rumbling. At the Earth's surface, earthquakes manifest themselves by shaking and displacing or disrupting the ground. When the epicenter of a large earthquake is located offshore, the seabed may be displaced sufficiently to cause ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hurricane Camile
Hurricane Camille was the second most intense tropical cyclone on record to strike the United States, behind the 1935 Labor Day hurricane. The most intense storm of the 1969 Atlantic hurricane season, Camille originated as a tropical depression on August 14, south of Cuba, from a long-tracked tropical wave. Located in a favorable environment for strengthening, the storm quickly intensified into a Category 2 hurricane before striking the western part of Cuba on August 15. Emerging into the Gulf of Mexico, Camille underwent another period of rapid intensification and became a Category 5 hurricane the next day as it moved northward towards the Louisiana–Mississippi region. Despite weakening slightly on August 17, the hurricane quickly re-intensified back into a Category 5 hurricane before it made landfall a half-hour before midnight in Bay St. Louis, Mississippi. At peak intensity, the hurricane had peak 1-minute sustained winds of 175 mph (280 km/h) and a min ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mississippi Delta
The Mississippi Delta, also known as the Yazoo–Mississippi Delta, or simply the Delta, is the distinctive northwest section of the U.S. state of Mississippi (and portions of Arkansas and Louisiana) that lies between the Mississippi and Yazoo Rivers. The region has been called "The Most Southern Place on Earth" ("Southern" in the sense of "characteristic of its region, the American South"), because of its unique racial, cultural, and economic history. It is long and across at its widest point, encompassing about , or, almost 7,000 square miles of alluvial floodplain. Originally covered in hardwood forest across the bottomlands, it was developed as one of the richest cotton-growing areas in the nation before the American Civil War (1861–1865). The region attracted many speculators who developed land along the riverfronts for cotton plantations; they became wealthy planters dependent on the labor of enslaved African Americans, who composed the vast majority of the populatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sediment
Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand and silt can be carried in suspension in river water and on reaching the sea bed deposited by sedimentation; if buried, they may eventually become sandstone and siltstone (sedimentary rocks) through lithification. Sediments are most often transported by water (fluvial processes), but also wind (aeolian processes) and glaciers. Beach sands and river channel deposits are examples of fluvial transport and deposition, though sediment also often settles out of slow-moving or standing water in lakes and oceans. Desert sand dunes and loess are examples of aeolian transport and deposition. Glacial moraine deposits and till are ice-transported sediments. Classification Sediment can be classified based on its grain size, grain shape, and c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deposition (geology)
Deposition is the geological process in which sediments, soil and rocks are added to a landform or landmass. Wind, ice, water, and gravity transport previously weathered surface material, which, at the loss of enough kinetic energy in the fluid, is deposited, building up layers of sediment. Deposition occurs when the forces responsible for sediment transportation are no longer sufficient to overcome the forces of gravity and friction, creating a resistance to motion; this is known as the null-point hypothesis. Deposition can also refer to the buildup of sediment from organically derived matter or chemical processes. For example, chalk is made up partly of the microscopic calcium carbonate skeletons of marine plankton, the deposition of which has induced chemical processes (diagenesis) to deposit further calcium carbonate. Similarly, the formation of coal begins with the deposition of organic material, mainly from plants, in anaerobic conditions. Null-point hypothesis The null ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Norway
Norway, officially the Kingdom of Norway, is a Nordic country in Northern Europe, the mainland territory of which comprises the western and northernmost portion of the Scandinavian Peninsula. The remote Arctic island of Jan Mayen and the archipelago of Svalbard also form part of Norway. Bouvet Island, located in the Subantarctic, is a dependency of Norway; it also lays claims to the Antarctic territories of Peter I Island and Queen Maud Land. The capital and largest city in Norway is Oslo. Norway has a total area of and had a population of 5,425,270 in January 2022. The country shares a long eastern border with Sweden at a length of . It is bordered by Finland and Russia to the northeast and the Skagerrak strait to the south, on the other side of which are Denmark and the United Kingdom. Norway has an extensive coastline, facing the North Atlantic Ocean and the Barents Sea. The maritime influence dominates Norway's climate, with mild lowland temperatures on the se ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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