Open AccessMagnetic mineralogy of the sediments in Lake Ådran, eastern Sweden, and an interpretation of early Holocene water level changes
Author(s) -
SANDGREN PER,
RISBERG JAN
Publication year - 1990
Publication title -
boreas
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.95
H-Index - 74
eISSN - 1502-3885
pISSN - 0300-9483
DOI - 10.1111/j.1502-3885.1990.tb00422.x
Subject(s) - geology , holocene , ferrimagnetism , environmental magnetism , structural basin , magnetic mineralogy , drainage basin , rock magnetism , diatom , magnetic susceptibility , hydrology (agriculture) , geochemistry , sediment , geomorphology , magnetization , paleontology , oceanography , remanence , magnetic field , physics , cartography , geotechnical engineering , quantum mechanics , geography
A number of magnetic parameters have been measured on samples from a master sequence in Lake Adran, eastern Sweden. Based on the results, frequency dependent magnetic susceptibility, high isothermal rem‐anence magnetization and different magnetic ratios have been calculated. The results from the master sequence have also been compared with magnetically analysed soil samples from the lake catchment. The results of the magnetic analyses show that the sediments in Lake Ådran originate from two sources, one regional and one local. The different sources can be related to water level changes during the Ancylus and Litorina stages. Sediments originating from the regional source are characterized by high ferrimagnetic to antiferromagnetic ratios (high S‐ratios) and are assumed to have been deposited when the water level was well above the threshold. Sediments derived from the catchment, having lower S‐ratios, are assumed to have been deposited when the basin was cut off from the regional water circulation. On the basis of the magnetic results, combined with pollen and diatom analyses, tentative water level changes for the Lake Adran basin are compiled.