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31-554: The district is characterized by the presence of a relatively large coastal plain , with high mountains to the east. The largest cities in Akkar are Halba, Bire Akkar and Al-Qoubaiyat . Akkar has many important Roman and Arabic archaeological sites. One of the most famous archaeological sites and the birthplace of the Roman emperor Severus Alexander (d.235) is the Tell of Arqa near

62-653: A country have become erodible. For example, on the Madagascar high central plateau , which constitutes approximately ten percent of that country's land area, most of the land area is devegetated, and gullies have eroded into the underlying soil to form distinctive gulleys called lavakas . These are typically 40 meters (130 ft) wide, 80 meters (260 ft) long and 15 meters (49 ft) deep. Some areas have as many as 150 lavakas/square kilometer, and lavakas may account for 84% of all sediments carried off by rivers. This siltation results in discoloration of rivers to

93-468: A dark red brown color and leads to fish kills. In addition, sedimentation of river basins implies sediment management and siltation costs.The cost of removing an estimated 135 million m of accumulated sediments due to water erosion only is likely exceeding 2.3 billion euro (€) annually in the EU and UK, with large regional differences between countries. Erosion is also an issue in areas of modern farming, where

124-432: A grain, such as pits, fractures, ridges, and scratches. These are most commonly evaluated on quartz grains, because these retain their surface markings for long periods of time. Surface texture varies from polished to frosted, and can reveal the history of transport of the grain; for example, frosted grains are particularly characteristic of aeolian sediments, transported by wind. Evaluation of these features often requires

155-458: A higher density and viscosity . In typical rivers the largest carried sediment is of sand and gravel size, but larger floods can carry cobbles and even boulders . Wind results in the transportation of fine sediment and the formation of sand dune fields and soils from airborne dust. Glaciers carry a wide range of sediment sizes, and deposit it in moraines . The overall balance between sediment in transport and sediment being deposited on

186-426: A hydrodynamic sorting process within the marine environment leading to a seaward fining of sediment grain size. One cause of high sediment loads is slash and burn and shifting cultivation of tropical forests. When the ground surface is stripped of vegetation and then seared of all living organisms, the upper soils are vulnerable to both wind and water erosion. In a number of regions of the earth, entire sectors of

217-470: A result, can cause exposed sediment to become more susceptible to erosion and delivery to the marine environment during rainfall events. Sediment can negatively affect corals in many ways, such as by physically smothering them, abrading their surfaces, causing corals to expend energy during sediment removal, and causing algal blooms that can ultimately lead to less space on the seafloor where juvenile corals (polyps) can settle. When sediments are introduced into

248-661: A sea coast. A fall line commonly marks the border between a coastal plain and an upland area. Some of the largest coastal plains are in Alaska and the southeastern United States . The Gulf Coastal Plain of North America extends northwards from the Gulf of Mexico along the Lower Mississippi River to the Ohio River , which is a distance of about 981 miles (1,579 km). The Atlantic Coastal Plain runs from

279-551: Is expected to be delivered to the outlet of the river. The sediment transfer and deposition can be modelled with sediment distribution models such as WaTEM/SEDEM. In Europe, according to WaTEM/SEDEM model estimates the Sediment Delivery Ratio is about 15%. Watershed development near coral reefs is a primary cause of sediment-related coral stress. The stripping of natural vegetation in the watershed for development exposes soil to increased wind and rainfall and, as

310-581: Is measured on a log base 2 scale, called the "Phi" scale, which classifies particles by size from "colloid" to "boulder". The shape of particles can be defined in terms of three parameters. The form is the overall shape of the particle, with common descriptions being spherical, platy, or rodlike. The roundness is a measure of how sharp grain corners are. This varies from well-rounded grains with smooth corners and edges to poorly rounded grains with sharp corners and edges. Finally, surface texture describes small-scale features such as scratches, pits, or ridges on

341-578: Is strategically importent as it is the northen gateway into Syria . this is why several castles were built in that area and in Syria. The most notable one is probebly Krak des Chevaliers in Syria. During the 19th century the Mir‘abi families of beys and pashas bought many lands in the area, which France found it helpfull with their Mandate over Lebanon. Up to the 1958 Syrian land reforms, the local population of Akkar could move freely in and out of Syria. During

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372-733: The Deccan Plateau , along the western and eastern coasts of India. They extend for about 6,150 km from the Rann of Kutch in the west to West Bengal in the east. They are broadly divided into the Western Coastal Plains and the Eastern Coastal Plains . The two coastal plains meet at Kanyakumari , the southernmost tip of the Indian mainland. The eastern coastal plain is located between The Bay of Bengal and

403-606: The District's 309,517 voters were roughly 69% Sunni , 13% Greek Orthodox , 10% Maronite Catholics , 5% Alawite , 1% Shia , and 2% others. This region is home to the second-largest population of Alawites in Lebanon. Turkish people form a majority in Kouachra and Aydamun . Coastal plain A coastal plain (also coastal plains , coastal lowland , coastal lowlands ) is an area of flat, low-lying land adjacent to

434-485: The New York Bight to Florida. Coastal plains can form in one of two ways. Some start as a continental shelf , a flat piece of land located below sea level, and are created when the ocean level falls, exposing the land. Others develop when river currents carry sediment into the ocean, which is deposited and builds up over time until it forms a coastal plain. The Coastal Plains of India lie on either side of

465-488: The 1970's the peasants of Akkar formed an alliance to fight the land owners and the system of which 3% of the population held about 73% of the land. They were led by Khalid Saghiya, a Syrian Baathist lawyer from Baynu. Following Black September in Jordan , firearms were accessible to all. A fact that escalated the revolt. The involvement of Syria in the area as well as the diverse population led to many rivalries. Franjieh and

496-479: The Phalange were rivals. Peasant laborers clashed with landlords, while Jurd clans, though occasionally in conflict with one another, had formed an alliance against the beys. Eventualy the discovey of oil in the gulf led to mass imigration, sparing the region and its population from the fate that came to many other parts of Lebanon. Akkar is divided into the following regions: As of 2022, the religious make-up of

527-600: The bed is given by the Exner equation . This expression states that the rate of increase in bed elevation due to deposition is proportional to the amount of sediment that falls out of the flow. This equation is important in that changes in the power of the flow change the ability of the flow to carry sediment, and this is reflected in the patterns of erosion and deposition observed throughout a stream. This can be localized, and simply due to small obstacles; examples are scour holes behind boulders, where flow accelerates, and deposition on

558-579: The body of water. Terrigenous material is often supplied by nearby rivers and streams or reworked marine sediment (e.g. sand ). In the mid-ocean, the exoskeletons of dead organisms are primarily responsible for sediment accumulation. Deposited sediments are the source of sedimentary rocks , which can contain fossils of the inhabitants of the body of water that were, upon death, covered by accumulating sediment. Lake bed sediments that have not solidified into rock can be used to determine past climatic conditions. The major areas for deposition of sediments in

589-417: The coastal regions of the ocean, the proportion of land, marine, and organic-derived sediment that characterizes the seafloor near sources of sediment output is altered. In addition, because the source of sediment (i.e., land, ocean, or organically) is often correlated with how coarse or fine sediment grain sizes that characterize an area are on average, grain size distribution of sediment will shift according to

620-472: The eastern Ghats and the western coastal plain is located between the Arabian Sea and the western Ghats. This article related to topography is a stub . You can help Misplaced Pages by expanding it . 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

651-422: The edges and corners of particle are. Complex mathematical formulas have been devised for its precise measurement, but these are difficult to apply, and most geologists estimate roundness from comparison charts. Common descriptive terms range from very angular to angular to subangular to subrounded to rounded to very rounded, with increasing degree of roundness. Surface texture describes the small-scale features of

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682-510: The flow. In geography and geology , fluvial sediment processes or fluvial sediment transport are associated with rivers and streams and the deposits and landforms created by sediments. It can result in the formation of ripples and dunes , in fractal -shaped patterns of erosion, in complex patterns of natural river systems, and in the development of floodplains and the occurrence of flash floods . Sediment moved by water can be larger than sediment moved by air because water has both

713-857: 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. Sediment can be classified based on its grain size , grain shape, and composition. Sediment size

744-539: The inside of meander bends. Erosion and deposition can also be regional; erosion can occur due to dam removal and base level fall. Deposition can occur due to dam emplacement that causes the river to pool and deposit its entire load, or due to base level rise. Seas, oceans, and lakes accumulate sediment over time. The sediment can consist of terrigenous material, which originates on land, but may be deposited in either terrestrial, marine, or lacustrine (lake) environments, or of sediments (often biological) originating in

775-406: The long, intermediate, and short axis lengths of the particle. The form ψ l {\displaystyle \psi _{l}} varies from 1 for a perfectly spherical particle to very small values for a platelike or rodlike particle. An alternate measure was proposed by Sneed and Folk: which, again, varies from 0 to 1 with increasing sphericity. Roundness describes how sharp

806-435: The marine environment include: One other depositional environment which is a mixture of fluvial and marine is the turbidite system, which is a major source of sediment to the deep sedimentary and abyssal basins as well as the deep oceanic trenches . Any depression in a marine environment where sediments accumulate over time is known as a sediment trap . The null point theory explains how sediment deposition undergoes

837-491: The relative input of land (typically fine), marine (typically coarse), and organically-derived (variable with age) sediment. These alterations in marine sediment characterize the amount of sediment suspended in the water column at any given time and sediment-related coral stress. In July 2020, marine biologists reported that aerobic microorganisms (mainly), in " quasi-suspended animation ", were found in organically-poor sediments, up to 101.5 million years old, 250 feet below

868-473: The removal of native vegetation for the cultivation and harvesting of a single type of crop has left the soil unsupported. Many of these regions are near rivers and drainages. Loss of soil due to erosion removes useful farmland, adds to sediment loads, and can help transport anthropogenic fertilizers into the river system, which leads to eutrophication . The Sediment Delivery Ratio (SDR) is fraction of gross erosion (interill, rill, gully and stream erosion) that

899-445: The surface of the grain. Form (also called sphericity ) is determined by measuring the size of the particle on its major axes. William C. Krumbein proposed formulas for converting these numbers to a single measure of form, such as where D L {\displaystyle D_{L}} , D I {\displaystyle D_{I}} , and D S {\displaystyle D_{S}} are

930-615: The town of Miniara . Several prehistoric sites were found in the Akkar plain foothills that were suggested to have been used by the Heavy Neolithic Qaraoun culture at the dawn of the Neolithic Revolution . Akkar can be divided into 7 parts: Qaitea (القيطع), Jouma (الجومة), Dreib (الدريب), Jabal Akroum (جبل أكروم), Wadi Khaled (وادي خالد), Cheft (الشفت) and As-Sahel (السهل). The Akkar area

961-494: The use of a scanning electron microscope . Composition of sediment can be measured in terms of: This leads to an ambiguity in which clay can be used as both a size-range and a composition (see clay minerals ). Sediment is transported based on the strength of the flow that carries it and its own size, volume, density, and shape. Stronger flows will increase the lift and drag on the particle, causing it to rise, while larger or denser particles will be more likely to fall through

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