首页
按字顺浏览
期刊浏览
卷期浏览
Holocene Glacial Geology of the Svea Lowland, Spitsbergen, Svalbard
|
Holocene Glacial Geology of the Svea Lowland, Spitsbergen, Svalbard
作者:
RowanDana E.,
PéwéTroy L.,
PéwéRichard H.,
StuckenrathRobert,
期刊:
Geografiska Annaler: Series A, Physical Geography
(Taylor Available online 1982)
卷期:
Volume 64,
issue 1-2
页码: 35-51
ISSN:0435-3676
年代: 1982
DOI:10.1080/04353676.1982.11880055
出版商: Taylor&Francis
数据来源: Taylor
摘要:
ABSTRACTThe Svea Lowland, located in eastern van Mijenfjorden, central Spitsbergen, is composed of both marine clay and glacial till. These deposits have been divided into three geologic units based on their differing lithology and topographic expression: (1) the Geikie Moraine, (2) the Dames Moraine, and (3) an organic-rich marine clay. The sediments were deposited during two surges of the Paula Glacier in Holocene time.The first surge of the Paula Glacier is suggested by the limited C-14 age range of marine mollusk shells, between 7800 and 8500 years old, incorporated in all three deposits. This surge provides a mechanism to kill the molluscs at this time while producing a deposit of limited-age material available for redeposition and incorporation with younger material by a later surge of the Paula Glacier.A second surge of the Paula Glacier is suggested by (1) the ice-cored nature of the moraine deposits on the lowland, (2) the semi-arcuate distribution of the moraine deposits traceable to the current glacial front, (3) young radiometric dates of driftwood and whalebone incorporated within and on the surface of the marine clay, and (4) the presence of a datable turf horizon underlying the glacially pushed marine clay. These features suggest this surge occurred between 600 and 250 years ago. As the Paula Glacier surged across the fjord, the fjordbottom clay, possibly deposited in the past by a previous surge, was both pushed before the advancing glacier and incorporated into its till. Some of the ice-shoved marine clay was pushed as a slab before the ice-cored Dames Moraine, over the existing tundra-covered lowland. Recent strandlines present up to 20 m above sea level surrounding Braganza Bay suggest that the Paula Glacier dammed Braganza Bay producing a lake at this time.Subsequent to the last surge, partial melting of the ice in the Dames Moraine has resulted in the striking knob and kettle terrain and associated small lakes over much of the area. A recent surge of the Sabbarp Glacier deformed moraine material (Dames Moraine) produced by the second surge of the Paula Glacier. Intense frost action has created frost-split debris on the moraine surfaces.
点击下载:
PDF (11808KB)
返 回
|
|