Aggradation
Aggradation (or alluviation) is the term used in geology for the increase in land elevation, typically in a river system, due to the deposition of sediment.Aggradation occurs in areas in which the supply of sediment is greater than the amount of material that the system is able to transport.After millions of years, an aggradational environment will become a sedimentary basin, which contains the deposited sediment, including paleochannels and ancient floodplains.Aggradation can be caused by changes in climate, land use, and geologic activity, such as volcanic eruption, earthquakes, and faulting.In 2009, a report by researchers from the University of Colorado at Boulder in the journal Nature Geoscience said that reduced aggradation was contributing to an increased risk of flooding in many river deltas.
geologydepositiontransportExner equationalluvialriversriver deltasalluvial fanssubsidencesedimentary basinpaleochannelsfloodplainsclimateland usevolcanic eruptionearthquakesfaultingfloodplainUniversity of Colorado at BoulderNature GeoscienceAvulsion (river)ProgradationWayback MachineDavid MohrigBBC News OnlineRiver morphologyAlluvial plainDrainage basinDrainage system (geomorphology)EstuaryStrahler number (stream order)River valleyRiver deltaRiver sinuosityAlluvial riversAnabranchBar (river morphology)Braided riverChannel patternCut bankMeanderMeander cutoffMouth barOxbow lakePoint barRiffleRapidsRiparian zoneRiver bifurcationRiver channel migrationRiver mouthSlip-off slopeStream poolThalwegBedrock riverCanyonKnickpointPlunge poolBedformsAntiduneCurrent rippleBase levelDegradation (geology)Erosion and tectonicsRiver rejuvenationDeposition (geology)Hack's lawHelicoidal flowPlayfair's lawSediment transportList of rivers that have reversed directionstreamsspringsAlluvial riverBlackwater riverChannelChannel typesConfluenceDistributarySubterranean riverRiver ecosystemRiver sourceTributaryArroyoBourneChalk streamCouleeCurrentStream bedStream channelStreamflowStream gradientPerennial streamWinterbourneEstavelle/InversacGeyserHoly wellHot springlist in the USKarst springMineral springRhythmic springSpring horizonSedimentary processeserosionAbrasionBed loadBed material loadGranular flowDebris flowDissolved loadDowncuttingHeadward erosionPalaeochannelRetrogradationSaltationSuspended loadWash loadWater gapAlluvial fanAntecedent drainage streamAvulsionBillabongFloating islandFluvial terraceMeander scar