ABSTRACT
ALTHOUGHTHISBOOKisnotprimarilyconcernedwiththe methodsofchronometricdating,noaccountofPost-Glacial chronologyintheBalticregionwouldbecompletewithout someaccountofvarveanalysis,developedbyBarondeGeer inSweden.89Asearlyas1878henoticedtheregularityofthe laminationofglacialclaysexposedinsectionsaroundStockholm,andcametotheconclusionthatthelaminae,whichwere paired,markedtheannualmeltingoftheiceasitreceded acrossSwedenattheendoftheIceAge.Ifthepairedlaminae orvarves 9 0 couldbecountedtheyshould,hededuced,provide arecordofthenumberofyearsthatelapsedbetweenonehalt intherecessionandthenext.Heorganizedsystematiccounting ofthevarvesinsectionsallacrossSwedenfromtheScanian morainesinthesouthtotheshoresofLakeRagundainthe north.Onlyasmallfractionofthetotalnumberofannual layersispreservedinanyonesection,butbyplottingthe variationinvarve-thicknessineachsectionandthenmatching identicalsequencesindifferentsectionsdeGeerandhiseoworkerswereabletocombinetherecordsandthusconstructa reasonablycompletechronologyoftherecession.Sectionswere measuredatintervalsofaboutonekilometrealongaseriesof mainlysouth-northtraverses;individualvarvescouldbe tracedfordistancesofuptomorethan50km,andprovedto overlaponeanotherinthedirectionofice-retreatliketilesona roof.
