Two types of ridging South Atlantic Ocean anticyclones over South Africa and the associated dynamical processes

ABSTRACTThe position of the Falkland Islands adjacent to the South American continental margin belies the close association of their geology with that of South Africa. A Mesoproterozoic basement is unconformably overlain by a Silurian to Devonian succession of fluvial to neritic and shallow marine, siliciclastic strata. This is disconformably succeeded by a largely Permian succession that, near its base, includes a glacigenic diamictite and, thence, passes upwards into a succession of deltaic and lacustrine strata. The lithological succession and the character of its deformation bear striking similarities to the Cape Fold Belt and Karoo retroarc foreland basin. Swarms of Early Jurassic dykes were coeval with the Karoo magmatism and the initial break-up of Gondwana; Early Cretaceous dykes were intruded during the opening of the South Atlantic Ocean. Offshore sedimentary basins surrounding the archipelago contain Late Jurassic to Palaeogene successions and are currently the focus of hydrocarbon exploration. Best known is the North Falkland Basin, a classic failed rift. To the SE, the passive margin, Falkland Plateau Basin may also be rift-controlled, whilst the South Falkland Basin is a foreland basin created at the boundary of the South American and Scotia plates. The role of the Falkland Islands during the breakup of Gondwana remains controversial. Compelling evidence from the onshore geology favours rotation of an independent microplate from an original position adjacent to the Eastern Cape, South Africa. Alternative interpretations, justified largely from offshore geology, favour extension of the Falkland Plateau as a fixed promontory from the South American margin.

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Toxigenicity and biogeography of the diatom Pseudo-nitzschia across distinct environmental regimes in the South Atlantic Ocean

Marine Ecology Progress Series ◽

10.3354/meps11027 ◽

2015 ◽

Vol 526 ◽

pp. 67-87 ◽

Cited By ~ 10

Author(s):

ML Guannel ◽

D Haring ◽

MJ Twiner ◽

Z Wang ◽

AE Noble ◽

...

Keyword(s):

Atlantic Ocean ◽

South Atlantic ◽

South Atlantic Ocean ◽

The South ◽

Environmental Regimes

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Individual variability in the settlement of juvenile green turtles in the western South Atlantic Ocean: relevance of currents and somatic growth rate

Marine Ecology Progress Series ◽

10.3354/meps12909 ◽

2019 ◽

Vol 614 ◽

pp. 173-182 ◽

Cited By ~ 2

Author(s):

P Campos ◽

L Cardona

Keyword(s):

Growth Rate ◽

Atlantic Ocean ◽

Somatic Growth ◽

Individual Variability ◽

South Atlantic ◽

South Atlantic Ocean ◽

Somatic Growth Rate ◽

Green Turtles

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Reconstruction of palaeoceanographic conditions in the South Atlantic Ocean at the last two Terminations based on calcareous dinoflagellate cysts

International Journal of Earth Sciences ◽

10.1007/s005310050297 ◽

2000 ◽

Vol 88 (4) ◽

pp. 680-693 ◽

Cited By ~ 29

Author(s):

O. Esper ◽

K. A. F. Zonneveld ◽

C. Höll ◽

B. Karwath ◽

H. Kuhlmann ◽

...

Keyword(s):

Atlantic Ocean ◽

South Atlantic ◽

South Atlantic Ocean ◽

Dinoflagellate Cysts ◽

The South ◽

Calcareous Dinoflagellate Cysts

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A juvenile Tristan albatross (Diomedea dabbenena) on land at the Crozet Islands

Polar Biology ◽

10.1007/s00300-020-02786-0 ◽

2020 ◽

Author(s):

Alexander L. Bond ◽

Christopher Taylor ◽

David Kinchin-Smith ◽

Derren Fox ◽

Emma Witcutt ◽

...

Keyword(s):

Atlantic Ocean ◽

Cytochrome B ◽

Adult Male ◽

Mitochondrial Gene ◽

Small Population ◽

South Atlantic ◽

South Atlantic Ocean ◽

Tristan Da Cunha ◽

Gough Island ◽

Dispersal Events

AbstractAlbatrosses and other seabirds are generally highly philopatric, returning to natal colonies when they achieve breeding age. This is not universal, however, and cases of extraordinary vagrancy are rare. The Tristan Albatross (Diomedea dabbenena) breeds on Gough Island in the South Atlantic Ocean, with a small population on Inaccessible Island, Tristan da Cunha, ca 380 km away. In 2015, we observed an adult male albatross in Gonydale, Gough Island, which had been ringed on Ile de la Possession, Crozet Islands in 2009 when it was assumed to be an immature Wandering Albatross (D. exulans). We sequenced 1109 bp of the cytochrome b mitochondrial gene from this bird, and confirmed it to be a Tristan Albatross, meaning its presence on Crozet 6 years previous, and nearly 5000 km away, was a case of prospecting behaviour in a heterospecific colony. Given the challenges in identifying immature Diomedea albatrosses, such dispersal events may be more common than thought previously.

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