Late quaternary vegetation history of the South-Tanganyika basin. Climatic implications in South Central Africa

AbstractPiston cores from the South Orkney Plateau penetrated overcompacted diamictons in water depths of up to 250 m. Detailed textural and petrological analyses of these diamictons indicate that they are basal tills. Seismic records from the plateau show a widespread surface of glacial erosion and provide additional evidence of an ice cap grounded to a depth of 250 m. Piston cores from the slope of the plateau penetrated diatomaceous muds resting directly on poorly sorted muds with very little to no biogenic material. The ice-rafted debris in these glacial-marine sediments is composed almost exclusively of material derived from the South Orkney Islands. This implies deposition beneath an ice shelf as opposed to iceberg rafting. In contrast, diatomaceous muds contain relatively abundant exotic iceberg-rafted material and reflect a glacial-maritime setting similar to that of today. The sharp contact separating diatomaceous surface sediments from basal tills and sub-ice shelf deposits indicates that the ice cap and ice shelf retreated from the plateau rapidly. Radiocarbon dates for diatomaceous muds from a glacial trough on the plateau indicate that the ice cap and ice shelf retreated from the plateau prior to 6000 to 7000 years ago. The homogeneity of surficial diatomaceous sediments suggests that sea ice conditions over the plateau have not changed radically since that time.

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Depositional Environments and History of Late Quaternary Sediments in Hudson Strait and Ungava Bay: Further Evidence from Seismic and Biostratigraphic Data

Géographie physique et Quaternaire ◽

10.7202/032917ar ◽

2007 ◽

Vol 46 (3) ◽

pp. 311-329 ◽

Cited By ~ 8

Author(s):

Brian MacLean ◽

Gustav Vilks ◽

Bhan Deonarine

Keyword(s):

Late Quaternary ◽

Depositional Environments ◽

Quaternary Sediments ◽

The South ◽

Bay Area ◽

South Central ◽

History Of ◽

Ams Dating ◽

Seafloor Sediments ◽

Glaciomarine Sediments

ABSTRACT Regional ship-borne investigations of seafloor sediments provide further information on late Quaternary depositional environments and history in the Hudson Strait-Ungava Bay region. Greatest sediment thicknesses, up to 130 m, occur in the large basin in eastern Hudson Strait and in the western Hudson Strait basin north of Charles Island. Significant deposits are also present in basins southwest of Charles Island, along the south central part of the Strait, and in the southern part of Ungava Bay. Glacial drift deposits are widespread, but glaciomarine and postglacial sediments mainly occur in the basinal areas, with glaciomarine sediments generally predominating. Glaciomarine sediments are laterally transitional to glacial drift in the south central part of the Strait, and at many other basin margins. AMS dating of the deepest shells found within three cores from the glaciomarine sequences in the Wakeham Bay-Baie Héricart region of south central Hudson Strait yielded ages of 8390 ± 70,8420 ± 80, and 8520 ± 80 BP. Sequences underlying the dated intervals may contain time equivalents of glaciomarine sediments 1000-2000 years older found onshore in the Deception Bay area by Gray, Bruneau, and others.

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Geology and Mesozoic structural history of the south-central Brooks Range, Alaska

Architecture of the Central Brooks Range Fold and Thrust Belt, Arctic Alaska ◽

10.1130/0-8137-2324-8.195 ◽

1998 ◽

Cited By ~ 4

Author(s):

Richard R. Gottschalk ◽

John S. Oldow ◽

H. G. Avé Lallemant

Keyword(s):

The South ◽

Brooks Range ◽

South Central ◽

Structural History ◽

History Of ◽

History Of The South

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Seismostratigraphy and Neogene-Recent depositional history of the south central continental margin of Cyprus

Marine and Petroleum Geology ◽

10.1016/0264-8172(93)90045-t ◽

1993 ◽

Vol 10 (5) ◽

pp. 426-438 ◽

Cited By ~ 10

Author(s):

Jean E. McCallum ◽

Roger A. Scrutton ◽

Alastair H.F. Robertson ◽

William Ferrari

Keyword(s):

Continental Margin ◽

The South ◽

Depositional History ◽

South Central ◽

History Of ◽

History Of The South

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Population dynamics in pre-Inca human groups from the Osmore Valley, the Azapa Valley and the coast of the South Central Andes

PLoS ONE ◽

10.1371/journal.pone.0229370 ◽

2020 ◽

Vol 15 (12) ◽

pp. e0229370

Author(s):

Alfredo Coppa ◽

Francesca Candilio ◽

Claudia Arganini ◽

Edmundo de la Vega Machicao ◽

Edmundo G. Moreno Terrazas ◽

...

Keyword(s):

Population Dynamics ◽

Central Andes ◽

Population History ◽

The South ◽

South Central ◽

Intermediate Phases ◽

Significant Movement ◽

History Of ◽

Population Continuity ◽

History Of The South

The present study applies a dental morphological perspective to the understanding of the complex pre-contact population history of the South Central Andes, through the detection of the underlying dynamics, and the assessment of the biological ties among groups. It presents an analysis of 1591 individuals from 66 sites that date from the Archaic to the Late Intermediate phases from Bolivia, Chile and Peru. The results suggest this area is characterized by significant movement of people and cultures and, at the same time, by long standing population continuity, and highlight the need for wider perspectives capable of taking into account both the different micro-regional realities and the region in its entirety.

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