scholarly journals Morphology and variations of glacial drainage basins in the King George Island ice field, Antarctica

1999 ◽  
Vol 29 ◽  
pp. 220-224 ◽  
Author(s):  
Jefferson C. Simões ◽  
Ulisses F. Bremer ◽  
Francisco E. Aquino ◽  
Francisco A. Ferron
Keyword(s):  
South Shetland Islands ◽  
Field Observations ◽  
Multispectral Imagery ◽  
King George Island ◽  
West Antarctica ◽  
Drainage Basins ◽  
Shetland Islands ◽  
Radio Echo Sounding ◽  
Ice Field ◽  
Glacial Cover

AbstractA Système probatoire pour l’observation de la terre (SPOT) mosaic of King George Island, the largest (1250 Km2) of the South Shetland Islands, West Antarctica, shows its major morphological features. Three main ice domes and 70 glacier drainage basins, covering 92.7% of the King George Island area, strongly controlled by the subglacial morphology and drained by relatively fast-moving tidewater outlet glaciers, were delineated. A general retreat of ice fronts through four decades, more intensely on the eastern side of the island (to the Bransfield Strait), resulted in the loss of about 7% of the glacial cover area. Superficial snow fades were derived from SPOT multispectral imagery and, together with field observations, allowed the transient-snowline elevation to be obtained The latter is estimated to have risen from about 200-250 m in the mid-1950s to 300-350 m by 1988. Spot radio-echo sounding surveys give an overview of the bedrock morphology.

scholarly journals Two additions to the moss flora of the South Shetland Islands in the maritime Antarctic

2018 ◽  
Vol 87 (4) ◽  
Author(s):  
Mariusz Wierzgoń ◽  
Tomasz Suchan ◽  
Michał Ronikier
Keyword(s):  
South Shetland Islands ◽  
King George Island ◽  
Maritime Antarctic ◽  
The South ◽  
Shetland Islands ◽  
Bay Area ◽  
Leading Position ◽  
Glacial Cover ◽  
The Antarctic ◽  
First Time

<em>Tortella fragilis</em> (Drumm.) Limpr. (Pottiaceae) and <em>Bryum nivale</em> Müll. Hal. (Bryaceae) are recorded for the first time from the South Shetland Islands in the northern maritime Antarctic. They were discovered in the Admiralty Bay area on King George Island, the largest island of this archipelago. The two species are briefly characterized morphologically, their habitats are described, and their distribution in the Antarctic is mapped. Discovery of these species has increased the documented moss flora of King George Island to 67 species, strengthening it in the leading position among individual areas with the richest diversity of moss flora in Antarctica. Likewise, <em>T. fragilis</em> and <em>B. nivale</em> represent remarkable additions to the moss flora of the South Shetland Islands, which currently consists of 92 species and one variety, making this archipelago by far the richest bryofloristically amongst large geographic regions of the Antarctic. Comparison of recent (2018) and old (1985) photographs revealed a significant retreat of glacial cover and suggests that the collection site was likely opened for colonization only within the last several decades. The record of <em>T. fragilis</em> is biogeographically relevant, and constitutes an intermediate site between the species’ occurrences in the Antarctic Peninsula and southern South America. The present record of <em>B. nivale</em> is the fourth discovery of the species worldwide, which may be helpful for the future designation of the distribution of this extremely rare species.

A new aspidostomatid bryozoan from the Cape Melville Formation (Lower Miocene) of King George Island, West Antarctica

2004 ◽  
Vol 16 (3) ◽  
pp. 319-327 ◽  
Author(s):  
URSZULA HARA ◽  
J. ALISTAIR CRAME
Keyword(s):  
New Species ◽  
Colony Growth ◽  
Morphological Characters ◽  
South Shetland Islands ◽  
King George Island ◽  
West Antarctica ◽  
Shetland Islands ◽  
Sedimentary Sequences ◽  
Early Neogene ◽  
A New Species

Fragments of large, bilamellar aspidostomatid bryozoan colonies occur in Early Miocene glaciomarine sedimentary sequences of the Cape Melville Formation, King George Island, South Shetland Islands, West Antarctica. Investigation of the morphological characters of this aspidostomatid cheilostome shows that it represents a new species, which is described herein as Aspidostoma melvillensis sp. n. A combination of the colony-growth pattern, inferred co-occurring biota and associated sedimentary structures indicates a comparatively deep-water, outer shelf palaeoenvironmental setting. This Miocene occurrence of Aspidostoma melvillensis sp.n. emphasizes a biogeographical link with adjacent Southern Hemisphere regions during the early Neogene.

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