Sediment
[1] It occurs naturally and, through the processes of weathering and erosion, is broken down and 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.Complex mathematical formulas have been devised for its precise measurement, but these are difficult to apply, and most geologists estimate roundness from comparison charts.Wind results in the transportation of fine sediment and the formation of sand dune fields and soils from airborne dust.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 can be localized, and simply due to small obstacles; examples are scour holes behind boulders, where flow accelerates, and deposition on the inside of meander bends.The major areas for deposition of sediments in 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.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.[14] This siltation results in discoloration of rivers to a dark red brown color and leads to fish kills.The cost of removing an estimated 135 million m3 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.[15] Erosion is also an issue in areas of modern farming, where the removal of native vegetation for the cultivation and harvesting of a single type of crop has left the soil unsupported.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.
River Tiber
discharging sediment into the ocean
Sediment (wine)River TiberTerrigenous (lithogenous)BiogenousRoundnessSortingGrain sizebouldercobblegravelpebblegranulecolloidooliteManganese nodulesOolitic aragonite sandTektitesBy processSedimentationSedimentary budgetSediment transportcoastalWeatheringErosionAeolian (windborne) transportBiomineralizationBioturbationCompactionConcretionExner equationFluvial processesGlacier flowice-sheet dynamicsice raftingLithificationSiltationTurbidity currentsBy structureSedimentary structuresBedformscross-beddingdunessgraded beddingripple marksAlluvial fanAlluvial riverPaleocurrent indicatorssole markingsimbricationRiver deltaSediment–water interfaceSedimentary basinSoft-sediment deformationUnconformityVegetation-inducedmatrixpore spacepermeabilitymorphologytextureCatenaSoil horizonSoil salinityHydropedologyMineralizationMicrobial calcite precipitationMarine sedimentAbyssal fanAragonitearagonite seaCalcitecalcite seaAmorphous calcium carbonateCalcificationContinental riseBay mudBioirrigationCoastal sediment transportCoastal sediment supplyEvaporitesMarine claypelagic red clayMarine regressiontransgressionPelagicturbiditecontouritehemipelagiteSalt tectonicsTidal bundleBiogenous sedimentsCalcareous oozebiogenic calcificationcalcareous nannoplanktonSiliceous oozebiogenic silicasilicificationdiatomaceous earthradiolariteMicrofossilReverse weatheringSoil biomantleSoil zoologysoil pathogensPedodiversitySoil biodiversityRhizosphereroot microbiomeSedimentary carbonSoil carbon storageSoil carbonSedimentary rockBadlandsCarbonateslimestonedolomiteClasticconglomeratebrecciasandstonemudrockEvaporiteGreywackeIron-richOrganic-richPhosphorite