1978 ◽  
Vol 129 ◽  
pp. 1-66
Author(s):  
S Funder

The Holocene stratigraphy in Scoresby Sund is based on climatic change as reflected by fluctuations in fjord and valley glaciers, immigration and extinction of marine molluscs, and the vegetation history recorded in pollen diagrams from five lakes. The histories are dated by C-14, and indirectly by emergence curves showing the patterns of isostatic uplift. From c. 10100-10400 to 9400 yr BP the major fjord glaciers showed oscillatory retreat with abundant moraine formation, the period of the Milne Land Moraines. The vegetation in the ice-free areas was a sparse type of fell field vegetation but with thermophilous elements indicating temperatures similar to the present. From 9400 yr BP the fjord glaciers retreated rapidly in the narrow fjords, the few moraines formed are referred to the Rødefjord stages and indicate topographically conditioned stillstands. At 8000 yr BP the low arctic Betula nana immigrated into the area, and in the period until 5000 yr BP dense dwarf shrub heath grew in areas where it is now absent. In the fjords the subarctic Mytilus edulis and Pecten islandica lived, suggesting a climate warmer than the present. From c. 5000 yr BP the dense dwarf shrub heath began to disappear in the coastal areas, and a 'poor' heath dominated by the high arctic Salix Arctica and Cassiope tetragona expanded. These two species, which are now extremely common, apparently did not grow in the area until c. 6000 yr BP. In lakes in the coastal area minerogenic sedimentation at c. 2800 yr BP, reflecting the general climatic deterioration.


1974 ◽  
Vol 111 (6) ◽  
pp. 481-500 ◽  
Author(s):  
G. S. Boulton ◽  
M. Rhodes

SummaryThe pattern of crustal warping in northern Spitsbergen as a result of widespread deglaciation is plotted. This is facilitated by the occurrence on ancient strandlines of pumice fragments at 4 major horizons14C dated at 6500 (A), 6200 (B), 4100 (C) and 2200 yearsb.p.(D). Trace element analyses indicate an origin for the pumice in the Jan Mayen area. At least 2 pumice horizons are thought to be contemporaneous with eruptions at 6500 and 4100 yearsb.p.


1963 ◽  
Vol S7-V (4) ◽  
pp. 543-554
Author(s):  
Andre Bonnet

Abstract Reconstruction of the Quaternary terraces of the Rhone (southeast France) reveals three or possibly four levels between the Rhone delta and the Rhone-Drome confluence. The age of the lowest terrace level--best exposed at Valence-Romans and upstream--is questionable. It may represent either the Wuerm or the Riss, or it may be divided between two different stades--neo-Riss and an older stade represented by the Leore-Fouillouse terrace. The middle terrace is Rissian and the highest terrace represents the Villafranchian. This phenomenon of uplifted terraces seems to be related to an isostatic uplift of blocks to compensate for the load of glacial ice. The continuity and extent of this phenomenon would explain the relative positions of the terraces, the older higher than the younger. Cross sections are included which show the recognized terraces. A correlation chart presents the Quaternary stratigraphy of Scandinavia, the alpine regions, the Sahara, central Africa, and Australia, and includes the major archaeological divisions.


2010 ◽  
Vol 29 (15-16) ◽  
pp. 1880-1893 ◽  
Author(s):  
P.T. Fretwell ◽  
D.A. Hodgson ◽  
E.P. Watcham ◽  
M.J. Bentley ◽  
S.J. Roberts

1970 ◽  
Vol 7 (3) ◽  
pp. 900-911 ◽  
Author(s):  
Brian R. Rust ◽  
John P. Coakley

Stanwell–Fletcher Lake is a cold monomictic Arctic lake, essentially isothermal at about 1.5 °C, with almost complete ice cover throughout the year. The annual heat input is about 13 000 cal cm−2, much less than that of dimictic Arctic lakes. The lake is isochemical, with very low ionic concentrations.The lake basin was formed during the Pleistocene by glacial scouring of soft sediments from a graben. As the ice retreated the basin filled with sea water, and became a fjord. Subsequent isostatic uplift raised the marine shorelines to 150 m above present sea level; the uplift curve indicates emergence of the fjord sill and termination of estuarine conditions about 3500 years ago. Tidal influx persisted for about 1100 years before the lacustrine phase started.Comparisons with modern fjords and coastal meromictic lakes suggest that most of the salt left the lake during its lacustrine phase. The mechanism was probably entrainment of salt water into a deep freshwater current flowing over the chemocline due to convective circulation in summer.


1993 ◽  
Vol 40 (1) ◽  
pp. 70-80 ◽  
Author(s):  
Ian D. Goodwin

AbstractA Holocene deglaciation sequence for the Windmill Islands was determined from the 14C age of raised marine shorelines, lakebottom sediments, and Adelie penguin remains found in abandoned rookeries. A north-south gradient in the elevation of the upper marine limit was observed, with the highest marine limit (31-32 m) observed on Browning Peninsula and Hull Island at the southern edge of the islands. Correspondingly, the southern islands were found to have been deglaciated by 8000 (corr.) yr B.P. while the northern islands were deglaciated by 5500 (corr.) yr B.P. Isostatic uplift rates were calculated as 0.5 to 0.6 m/100 yr, with an estimated total uplift of around 53 m which indicates late Pleistocene ice sheet thicknesses of 200 and 400 m over the islands and adjacent Petersen Bank, respectively. The margin of the Late Pleistocene grounded ice sheet extended an estimated 8-15 km offshore which coincides with the location of the 200 m isobath.


2007 ◽  
Vol 38 (2) ◽  
pp. 185-192
Author(s):  
Daniel E. Kerr

ABSTRACT A detailed stratigraphie analysis was carried out on a river-bank section of late Quaternary marine sediments in the Richardson River Basin, N.W.T. The sedimentary sequence represents a gradual shallowing of the sea in an estuarine environment, from a relatively shallow marine faciès to an intertidal environment. The withdrawal of the sea from the Richardson River Basin began prior to 10,300 years BP. Isostatic uplift caused the gradual regression of the sea to its present-day level. The marine sediments yielded 26 ostracode and 14 foraminifer species. Faunal evidence is indicative of brackish-water marginal marine conditions resulting from the dilution of nearshore marine waters by freshwater discharge from the many streams and rivers draining the basin of the Richardson River.


2001 ◽  
Vol 30 (1) ◽  
pp. 17-30 ◽  
Author(s):  
Matti Eronen ◽  
Gunnar Glückert ◽  
Lassi Hatakka ◽  
Orson van de Plassche ◽  
Johannes van der Plicht ◽  
...  

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