Sökning: "early Eocene"

Visar resultat 1 - 5 av 10 avhandlingar innehållade orden early Eocene.

  1. 1. Atmospheric dynamics and the hydrologic cycle in warm climates

    Författare :Henrik Carlson; Rodrigo Caballero; Johan Nilsson; Jonathan L. Mitchell; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; superrotation; early Eocene; warm climates; Madden-Julian Oscillation; the hydrologic cycle; vegetation sensitivity; large-scale circulation; atmosfärvetenskap och oceanografi; Atmospheric Sciences and Oceanography;

    Sammanfattning : Past warm climates represent one extreme of Earth's known climate states. Here, we study warm climates in both idealized simulations and full-complexity general circulation model (GCM) simulations of the early Eocene epoch, approximately 50 million years ago. LÄS MER

  3. 2. An attempt based on an interpretation of multichannel reflection seismic data to delineate sedimentary sequences, structures and evolution in the part of the Western Barents Sea 72° - 74°N and 10° - 17°E

    Författare :Lars Ole Boldreel; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Tillämpad geofysik; Applied Geophysics;

    Sammanfattning : This thesis is an attempt to throw further light on the structural development of the passive continental margin of the Western Barents Sea in the area from 72000'N to 74000'N and from 17000'E to 10000'E. It is based mainly on multichannel reflection seismics but available aeromagnetic, shipborne magnetic and free-air gravimetric data have also been analyzed. LÄS MER

  4. 3. Systematics and assessment of the chemosynthetic bivalve family Vesicomyidae

    Författare :Frida Hybertsen; Steffen Kiel; Helen Coxall; Elizabeth Harper; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Cenozoic; deep sea; hydrocarbon seeps; chemosynthetic; Bivalvia; Vesicomyidae; maringeologi; Marine Geology;

    Sammanfattning : The deep ocean has fascinated researchers for centuries with discoveries of new ecosystems and species, yet there are still many biogeographic and evolutionary questions unanswered. Along active and passive tectonic margins, specialized ecologies thrive in a symbiosis between chemosynthesizing bacteria and their host animals. LÄS MER

  5. 4. Fossil birds: Contributions to the understanding of avian evolution

    Författare :Johan Dalsätt; Otto Hermelin; Per Ericson; Zbigniew M. Bocheński; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; General and Historical Geology; allmän och historisk geologi;

    Sammanfattning : The study of the evolution of birds began about 150 years ago with the finding of Archaeopteryx. Yet, many unsolved questions about avian evolution remain to be answered. This thesis aims at addressing some of these questions.The Early Cretaceous Confusiusornis is the most well-represented Mesozoic bird in the fossil record. LÄS MER

  7. 5. Diversification on an ancient Darwinian island : Evolutionary history of caddisflies (Trichoptera) and other organisms on New Caledonia

    Författare :Marianne Espeland; Kjell Arne Johanson; Niklas Wahlberg; Michael Balke; Stockholms universitet; []
    Nyckelord :New Caledonia; Trichoptera; island; biogeography; phylogenetics; DNA; dispersal; vicariance; adaptation; ultramafic; diversification; new species; environmental factors; Systematic Zoology; zoologisk systematik och evolutionsforskning;

    Sammanfattning : Islands are either of continental or oceanic origin, and the biota of such islands are a result of vicariance and dispersal, respectively. New Caledonia, in the South Pacific, is a part of former Gondwana, but the origin of its biota is heavily debated. LÄS MER