Open AccessLake Boksehandsken's earliest postglacial sediments and their palaeoenvironmental implications, Jameson Land, East Greenland
Author(s) -
BJÖRCK SVANTE,
BENNIKE OLE,
INGÓLFSSON ÓLAFUR,
BARNEKOW LENA,
PENNEY DAVID N.
Publication year - 1994
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.1502-3885.1994.tb00613.x
Subject(s) - geology , macrofossil , deglaciation , preboreal , paleontology , lithology , marine transgression , stratigraphy , sedimentary depositional environment , glacial period , radiocarbon dating , oceanography , holocene , structural basin , younger dryas , tectonics
Lake Boksehandsken, the largest lake on Jameson Land, central East Greenland, is situated 54 m a.s.l. and holds a long (6.3 m) and complex stratigraphy. It was analysed with respect to lithology, carbon content, 14 C, micro‐ and macrofossils. The diamict material in the bottom is overlain by a fining‐upwards sequence, possibly deposited close to a receding ice margin in a glaciomarine environment. These deposits are interpreted to have been formed at the time of the marine limit ( c . 70 m) in the area. In spite of a large series of 14 C datings, very few of the obtained dates were considered reliable. This is because the sediments contain coal fragments and old redeposited plant remains. Based on a set of arguments and correlations to the surrounding glacial stratigraphy it is implied that the marine limit and deglaciation cannot be much older than 10,000 BP. The lithology of the lake sediments, in combination with occurrence of marine macrofossils. shows that deglaciation was succeeded by a (glacio)marine depositional environment. The lake was isolated from the sea at c . 9000 BP. followed by a short transgression and a final isolation at c . 8400 BP. This sequence of events is demonstrated by both litho‐and biostratigraphy and possible causes are discussed. A later oscillation some time between 8000 and 7500 BP. evidenced by litho‐, carbon‐, pollen‐ and Pecliastrum stratigraphy, is interpreted as a regional climatic cooling possibly correlatable to a distinct δ 18 O minima in the Greenland ice cores.