scholarly journals A New Southern North Atlantic Isochron Map: Insights Into the Drift of the Iberian Plate Since the Late Cretaceous

2017 ◽  
Vol 122 (12) ◽  
pp. 9603-9626 ◽  
Author(s):  
Chiara Macchiavelli ◽  
Jaume Vergés ◽  
Antonio Schettino ◽  
Manel Fernàndez ◽  
Eugenio Turco ◽  
...  
Keyword(s):  
Late Cretaceous ◽  
North Atlantic ◽  
Iberian Plate

Late cretaceous ocean circulation in the south Atlantic and Pacific oceans

2019 ◽  
Author(s):  
◽  
Shannon Haynes
Keyword(s):  
Indian Ocean ◽  
Ocean Circulation ◽  
Late Cretaceous ◽  
North Atlantic ◽  
High Latitude ◽  
Climate Model ◽  
South Atlantic ◽  
Regional Studies ◽  
Circulation Patterns ◽  
Insight Into

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT REQUEST OF AUTHOR.] Cooling during the last 15 million years of the Cretaceous is widely believed to have resulted in a reorganization of ocean circulation, with cooler periods being associated with deep ocean convection in high latitude regions (e.g., Robinson et al., 2010; MacLeod et al., 2011; Robinson and Vance, 2012; Jung et al., 2013). Understanding the relationship between climate change and sub-surface ocean circulation patterns, and gaining further insight into how circulation dynamics were influenced by the unique Cretaceous paleobathymetry is crucial to furthering our understanding of global climate dynamics during the Late Cretaceous. To provide further insight into Late Cretaceous ocean circulation we used neodymium isotopes as a tool to infer past ocean circulation patterns. Neodymium was extracted from fossilized fish teeth and bone fragments from bulk rock samples at 26 different sites (4 Pacific, 12 South Atlantic, 3 North Atlantic, 3 proto-Indian Ocean). We present two regional studies that focus on Campanian (84-72 Ma) and Maastrichtian (72-66 Ma) circulation patterns in the Pacific (Chapter 2) and South Atlantic (Chapter 3) Oceans. These chapters argue that, by the end of the Cretaceous, climate had cooled enough to support high latitude convection but also that circulation patterns were tightly controlled by bathymetry. To investigate the global implications of these two regional studies we also present preliminary neodymium isotopic data from several sites in the North Atlantic and proto-Indian Ocean (Chapter 4). Further, neodymium isotopic trends were compared to climate model simulations as well as to previously published neodymium, carbon, and oxygen isotopic records.

scholarly journals Plate tectonic reconstructions and paleogeographic maps of the central and North Atlantic oceans 1This article is one of a series of papers published in this CJES Special Issue on the theme of Mesozoic–Cenozoic geology of the Scotian Basin. 2Earth Sciences Sector Contribution 20120172.

2012 ◽  
Vol 49 (12) ◽  
pp. 1395-1415 ◽  
Author(s):  
Jean-Claude Sibuet ◽  
Stéphane Rouzo ◽  
Shiri Srivastava
Keyword(s):  
Nova Scotia ◽  
North America ◽  
Magnetic Anomaly ◽  
Late Cretaceous ◽  
North Atlantic ◽  
West African ◽  
Late Triassic ◽  
West African Coast ◽  
African Coast ◽  
Salt Deposits

We have established a new plate kinematic model of the central and North Atlantic oceans between North America, Africa, Meseta, Iberia, Flemish Cap, and Galicia Bank from Late Triassic to Late Cretaceous to better understand the nature and timing of rifting of Nova Scotia and Morocco conjugate continental margins since Late Triassic. The maps of salt distributions at the Sinemurian–Pliensbachian limit (190 Ma; after salt deposition) and in middle Bajocian (170 Ma) show that an area of the Nova Scotia margin is devoid of allochthonous salt and that an area of similar size located oceanward of the West African Coast Magnetic Anomaly shows salt deposits, suggesting that a portion of the Nova Scotia margin with its overlying salt deposits could have been transferred onto the Moroccan side right after the formation of the conjugate East Coast Magnetic Anomaly and West African Coast Magnetic Anomaly. Seven paleogeographic maps, from Late Triassic to Late Cretaceous, are presented with structural elements and magnetic lineations. They show that the connection between the Central Atlantic and the Tethys, with an aborted rift between Iberia and North America ending in the north against the Flemish Cap – Galicia Bank dam, started to deepen at the end of the first rifting phase (190 Ma ago) after the rupture of the thinned continental crust. It is only during the Early Cretaceous, after the rupture of the Flemish Cap – Galicia Bank dam, that the deep connection around Iberia was finally established between the Central and North Atlantic, the Tethys, and the Bay of Biscay.

FAUNAL RELATIONSHIPS BETWEEN EASTERN NORTH AMERICA AND EUROPE AS SHOWN BY INSECTS

1988 ◽  
Vol 120 (S144) ◽  
pp. 39-53 ◽  
Author(s):  
Gerald R. Noonan
Keyword(s):  
North America ◽  
Late Cretaceous ◽  
North Atlantic ◽  
North American ◽  
Eastern North America ◽  
Western North America ◽  
The North ◽  
The North Atlantic ◽  
Fossil Data ◽  
Suitable Land

AbstractThe supercontinent of Pangaea, which once included most lands, fragmented during the Mesozoic. By the Late Cretaceous there were two northern land masses that were strikingly different from those of present day: Asiamerica consisting of present western North America and Asia; and Euramerica comprising Europe and eastern North America. Mild climates facilitated the spread of terrestrial organisms within each of these land masses, but epicontinental seas hindered movements between Europe and Asia and between eastern and western North America.The insects of Euramerica presumably once formed a fauna extending from eastern North America to Europe that differed from the fauna of Asiamerica. The opening of the North Atlantic separated insects in Europe from those in eastern North America. This produced vicarious patterns, with some insects of eastern North America now being more closely related phylogenetically to those of Europe than to those of western North America. Most groups of insects have not been examined for such trans-Atlantic vicariances, but studies reviewed in this paper suggest such relationships for some groups of Collembola, Hemiptera, Homoptera, Coleoptera, Diptera, and Hymenoptera.The last suitable land connections between Europe and eastern North America were severed approximately 20–35 million years ago. The insects separated by this severance evolved at different rates. Some groups split in this way have apparently undergone little evolution and have the same species on both sides of the North Atlantic, but other vicarious groups have differentiated into taxa that are now distinct at specific and supra-specific levels.The opening of the North Atlantic probably split both tropical- and temperate-adapted insects in Euramerica. However, without fossil data it is difficult to identify the biogeographical patterns resulting from such splitting of the tropical-adapted groups. Most presently recognized European and eastern North American vicarious patterns of insects were probably caused by division of Euramerica rather than dispersal across Beringia.

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