An anisotropy of magnetic susceptibility (AMS) fabric record of till kinematics within a Late Weichselian low Baltic till, southern Sweden
Number of Authors: 4
2016 (English)In: Boreas, ISSN 0300-9483, E-ISSN 1502-3885, Vol. 45, no 4, 846-860 p.Article in journal (Refereed) Published
Herein we report on the results of an anisotropy of magnetic susceptibility (AMS) fabric case-study of two Late Weichselian tills exposed in a bedrock quarry in Dalby, Skane, southern Sweden. The region possesses a complex glacial history, reflecting alternating and interacting advances of the main body of the Scandinavian Ice Sheet (SIS) and its ice lobes from the Baltic basin, perhaps driven by streaming ice. AMS till fabrics are robust indicators of ice-flow history and till kinematics, and provide a unique tool to investigate till kinematics within and amongst till units. The till section investigated here contains similar to 8m of the Dalby Till - a dark grey silt-clay rich till deposited during one or more Baltic advance - overlain by similar to 1.5m of the regional surface diamicton. AMS fabrics within the lower part of the Dalby Till conform to the regional surface fluting, and reflect sustained flow from the ENE with progressive increases in basal strain. A boulder-rich horizon approximately 3m from the base of the till marks a restricted excursion in till fabric direction, fabric strength and style of strain. Ice flow is from the SW and W in the upper section. We interpret these fabrics to record shifting ice flow and bed conditions at the margins of the Young Baltic Advance ice lobe in southern Sweden, prior to a short-lived re-advance of the main body of the SIS over mainland Sweden recorded by the surface diamicton.
Place, publisher, year, edition, pages
2016. Vol. 45, no 4, 846-860 p.
Earth and Related Environmental Sciences
IdentifiersURN: urn:nbn:se:su:diva-136099DOI: 10.1111/bor.12192ISI: 000385405900017OAI: oai:DiVA.org:su-136099DiVA: diva2:1050901