2008 Joint Meeting of The Geological Society of America, Soil Science Society of America, American Society of Agronomy, Crop Science Society of America, Gulf Coast Association of Geological Societies with the Gulf Coast Section of SEPM

Paper No. 1
Presentation Time: 8:00 AM-4:45 PM

Polar Crossroads: High Latitude Biogeographic Highways


MAIN, Derek, Earth and Environmental Science, University of Texas at Arlington, Box 19049, 500 Yates St, Arlington, TX 76019 and SCOTESE, Christopher, PALEOMAP Project, University of Texas at Arlington, 700 Tanglewood Lane, Arlington, TX 76012, maindinos@msn.com

When Pangea broke apart in the Late Jurassic, widening ocean basins separated land areas in tropical and temperate latitudes. However, at the North and South Poles, land areas remained connected throughout most of the Jurassic, Cretaceous and Cenozoic. In the northern hemisphere, terrestrial migration routes can be traced eastwards from Greenland to Europe and northern Asia throughout the Triassic, Jurassic, Cretaceous and through the Cenozoic until the Oligocene. Connections between western North America and northeastern Eurasia, through Beringia, were more sporadic, but a good case can be made that Arctic Canada and Siberia were connected continuously since the Albian (~100 Ma). In the southern hemisphere, migration pathways were more complex. South America, Africa, Madagascar, India, Antarctic and Australia were interconnected from the Triassic, throughout the Jurassic and into the late Cretaceous (~100 Ma). In the late Aptian – early Albian, India and Madagascar became isolated from the other Gondwana continents. India became an island continent shortly thereafter (~90 Ma). Migration from South America down the West Antarctic peninsula, across Antarctica and into Australia was possible until the establishment of the Drake Passage and Tasman-Antarctic strait (~ 40 Ma). In this paper we will present 15 paleogeographic maps centered on the North South Poles that illustrate the polar biogeographic highways and crossroads that connected the continents during the Jurassic, Cretaceous and Cenozoic.