Dark earth

In geology and archaeology, dark earth is a substratum, up to 1 meter (3.1 feet) thick, that indicates settlement over long periods of time.The material is high in organic matter, including charcoal, which gives it its characteristic dark colour; it may also contain fragments of pottery, tile, animal bone and other artefacts.Dark earth over 7 hectares (17 acres) has been found in the Viking city of Björkö (today called Birka), in central Sweden, close to modern Stockholm.[citation needed] Dark earths occur around ruins in the Upper Guinean forests of Ghana, Guinea, Liberia and Sierra Leone.[9][10] For a period of at least 700 years, West African farmers have enriched the rain forest soils around their towns with compost derived from kitchen, animal, agricultural, and fire waste to produce a signature dark earth.
Restored blackhouse in a museum on Trotternish , Skye . There is no chimney on this house and the thatch becomes impregnated with soot. When the roof is replaced, the waste thatch can add fertility to the soil, resulting in dark earth.
Dark EarthBlack earthgeologyarchaeologysubstratumTrotternishchernozemRussiaHebrides"black houses"Achill Islandterra pretaEnglandLondiniumSwedenUppåkraScaniaBjörköStockholmKöpingsvikÖlandUpper Guinean forestsGuineaLiberiaSierra LeonePortugueseIndiananthropogenicAmazon BasincharcoalTerra rossaTerramare cultureBibcodeHuman EcologyFront Ecol EnvironSoil classificationWorld Reference Base for Soil ResourcesAcrisolsAlisolsAndosolsAnthrosolsArenosolsCalcisolsCambisolsCryosolsDurisolsFerralsolsFluvisolsGleysolsGypsisolsHistosolKastanozemsLeptosolsLixisolsLuvisolsNitisolsPhaeozemsPlanosolsPlinthosolsPodzolsRegosolsRetisolsSolonchaksSolonetzStagnosolTechnosolsUmbrisolsVertisolsUSDA soil taxonomyAlfisolsAndisolsAridisolsEntisolsGelisolsHistosolsInceptisolsMollisolsOxisolsSpodosolsUltisolsFAO soil classificationUnified Soil Classification SystemAASHTO Soil Classification SystemRéférentiel pédologiqueCanadian system of soil classificationAustralian Soil ClassificationPolish Soil Classification1938 USDA soil taxonomyList of U.S. state soilsList of vineyard soil typesTopsoilSubsoilSoil crustClaypanHardpanGypcrustCalicheParent materialPedosphereLaimosphereRhizosphereBulk soilAlkali soilBay mudBlue gooBrickearthBrown earthCalcareous grasslandDry quicksandDuplex soilEluviumExpansive clayFill dirtFuller's earthHydrophobic soilLunar soilMartian soilMuskegPaleosolPrime farmlandQuicksandSerpentine soilSpodic soilStagnogleySubaqueous soilTropical peatYedoma