A marginal marine ichnofauna from the Blaiklock Glacier Group (?Lower Ordovician) of the Shackleton Range, Antarctica

2003 ◽  
Vol 94 (1) ◽  
pp. 1-20 ◽  
Author(s):  
B. Weber ◽  
S. J. Braddy
Keyword(s):  
South Africa ◽  
Marine Water ◽  
Width Ratio ◽  
Shallow Marine ◽  
Median Ridge ◽  
The North ◽  
Table Mountain ◽  
Palaeomagnetic Data ◽  
Lower Ordovician ◽  
North Western

ABSTRACTA diverse arthropod-dominated ichnofauna, associated with a poorly preserved crustacean fauna and soft-bodied ?medusoid impressions, is described from the Blaiklock Glacier Group of the north-western Shackleton Range (Coats Land), Antarctica. The ichnofauna consists of Asaphoidichnus, Beaconites, Didymaulichnus, Diplichnites, Gordia, ?Laevicyclus, Merostomichnites, Monomorphichnus, Palaeophycus, Planolites, Rusophycus, Selenichnites, and Taphrhelminthoides (ichnogen nov.). Three new ichnotaxa are recognised: Taphrhelminthoides antarcticus n. ichnogen. et ichnosp. is a bilobate trail, composed of two parallel flat lobes, separated by a median ridge with a characteristic figure-of-eight pattern. Merostomichnites gracilis n. ichnosp. is characterised by its proportions (external:internal width ratio >3) and series of 10 to 12, thin, linear tracks. Selenichnites antarcticus n. ichnosp. is characterised by small elongate horseshoe-shaped marks, the medial portion showing three to five transverse scratch-marks.The palaeoenvironment is interpreted as extremely shallow marine water, possibly a tide-dominated estuary, based on sedimentological evidence and the composition of the ichnofauna. Radiometric and palaeomagnetic data indicate that this assemblage is Lower Ordovician in age, representing the first autochthonous Ordovician fossiliferous succession to be described from Antarctica. The succession shows several sedimentological and palaeontological similarities with the basal units of the Ordovician Table Mountain Group in South Africa, supporting palaeogeographic models placing the Palaeozoic Blaiklock basin close to the Ordovician Table Mountain basin.

The vegetation of the north-western Orange Free State, South Africa. 1. Physical environment

Bothalia ◽  
1990 ◽  
Vol 20 (2) ◽  
pp. 233-240
Author(s):  
M. S. Kooij ◽  
G. J. Bredenkamp
Keyword(s):  
South Africa ◽  
Physical Environment ◽  
Vegetation Classification ◽  
Free State ◽  
The North ◽  
Contextual Framework ◽  
Land Types ◽  
North Western

The physiography, geology, soil, land types and climate of the north-western Orange Free State are described. The description provides a contextual framework for the subsequent vegetation classification.

A new Mediterranean ‘lithistid’ sponge, Aciculites mediterranea sp. nov. (Porifera: Demospongiae) from a dark marine cave in Sardinia

2006 ◽  
Vol 86 (4) ◽  
pp. 691-698 ◽  
Author(s):  
Renata Manconi ◽  
Annalisa Serusi ◽  
Andrzej Pisera
Keyword(s):  
New Species ◽  
Mediterranean Sea ◽  
Growth Form ◽  
First Record ◽  
Shallow Marine ◽  
The North ◽  
The Mediterranean ◽  
North Western ◽  
Lithistid Sponge ◽  
Diagnostic Traits

A first record of the genus Aciculites in the Mediterranean Sea and the description of Aciculites mediterranea sp. nov. are here presented from a faunistic survey in a dark shallow marine cave of the north-western Sardinian karstic area. The new species is characterized by a massive cerebellum-like growth form, and a peculiar distribution of inhalant and exhalant areas, respectively, in depressed and elevated portions of the sponge surface. Oscules show a long narrow atrial cavity. Ectosomal skeleton is made of tangential anisostrongyles on elevated areas, and more or less vertical tufts of anisostrongyles in depressed inhalant areas. Anisostrongyles are smooth or with tips ornated by irregular tubercles. Sigmaspire microscleres are lacking. Choanosomal skeleton with tubercled irregular rizhoclone desmas and few scattered and variably oriented anisostrongyles. A comparative analysis of Aciculites mediterranea sp. nov. versus morphological diagnostic traits, geographical range and habitat of the species hitherto ascribed to Aciculites confirms that the peculiar distribution of the genus supports its relic condition of an ancient Tethyan fauna in the Mediterranean Sea.

XXI.—Geology and Petrology of the Dolerites of Spitsbergen

1934 ◽  
Vol 53 ◽  
pp. 284-321 ◽  
Author(s):  
G. W. Tyrrell ◽  
K. S. Sandford
Keyword(s):  
South Africa ◽  
South America ◽  
The North ◽  
Franz Josef Land ◽  
The World ◽  
North Western

Within the group of islands which together comprise Spitsbergen outcrops of dolerite may be traced over an area of about 50,000 square miles. The area is doubled if the neighbouring dolerites and basalts of Franz Josef Land are included. Even so, this is but a part of a network widely spread over the north-western part of the Euro-Asiatic continental platform, and over adjoining circumpolar lands. The sill-swarms of Spitsbergen alone rival in extent any of approximately similar age in other parts of the world, such as those of South Africa, South America, India, Antarctica, or North Britain. They merit a great deal more attention than it has yet been possible for geologists to devote to them.

scholarly journals Preliminary report on osteochondrosis in cattle in the north-western parts of South Africa

2016 ◽  
Vol 83 (1) ◽  
Author(s):  
Leon Prozesky ◽  
Johan Neser ◽  
Heinz Meissner ◽  
Kenneth Botha ◽  
Lubbe Jacobs ◽  
...  
Keyword(s):  
South Africa ◽  
Clinical Signs ◽  
Trace Minerals ◽  
Severe Drought ◽  
Chronic Metabolic Acidosis ◽  
The North ◽  
Rock Formations ◽  
Mineral Imbalance ◽  
North Western

The north-western part of South Africa, in particular, is well known for mineral imbalances. Aphosphorosis, resulting in rickets and osteomalacia, received a lot of attention at the turn of the nineteenth century (1882–1912). This was followed in 1997 by research on Vryburg hepatosis, another area-specific mineral imbalance–related disease in young calves reared on manganese-rich soil derived from the weathering of dolomitic (carbonate) rock formations. In 1982, a totally new syndrome (osteochondrosis) manifested in, amongst others, areas in South Africa where aphosphorosis was rife. Osteochondrosis was also identified in the south-western parts of Namibia as well as southern Botswana and other areas in South Africa. Osteochondrosis has a multifactorial aetiology and this study focused on the role of minerals, particularly phosphorus, in the development of the disease. A significant improvement in the clinical signs in experimental animals and a reduction of osteochondrosis occurred on farms where animals received bioavailable trace minerals and phosphorus as part of a balanced lick. An increase in the occurrence of the disease on farms during severe drought conditions in 2012–2013 prompted researchers to investigate the possible role of chronic metabolic acidosis in the pathogenesis of the disease.

scholarly journals Mineralogical-Petrographic Study of the Thaba Mine, Western Bushveld (South Africa)

2021 ◽  
Vol 20 (2) ◽  
pp. 160-171
Author(s):  
E.M. Tomilina ◽  
◽  
R.G. Iblaminov ◽  
Keyword(s):  
South Africa ◽  
Vertical Profile ◽  
Bushveld Complex ◽  
Middle Group ◽  
The North ◽  
Mineralogical Study ◽  
Petrographic Study ◽  
North Western

Here we present results of a detailed petrographic and mineralogical study of rock textures in a vertical profile through the Middle Group chromitite layers at the Thaba mine in the north-western part of the Bushveld Complex, South Africa

scholarly journals Notes on amphibia in the Tsitsikama National Parks

Koedoe ◽  
1977 ◽  
Vol 20 (1) ◽  
Author(s):  
V.C. Carruthers ◽  
G.A. Robinson
Keyword(s):  
South Africa ◽  
National Parks ◽  
National Park ◽  
The North ◽  
Table Mountain ◽  
Indigenous Forest

The Tsitsikama Coastal National Park, Republic of South Africa, is situated between 23 30'E and 24 15'E and along the 34 02'S latitude whereas the Tsitsikama Forest National Park is a small indigenous forest (478 ha) situated approximately 8 km to the north of the Coastal Park. Geologically the area is dominated by the Table Mountain Series (Toerien 1976) and the soils, particularly those of the forest are usually very acid.

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