Sökning: "Devonian"

Visar resultat 6 - 10 av 16 uppsatser innehållade ordet Devonian.

1. 6. The Metamorphic History of the Helags Mountain Area, Scandinavian Caledonides

   Master-uppsats, Uppsala universitet/Institutionen för geovetenskaper

   Författare :Sara Johansson; [2016]
   Nyckelord :Seve Nappe Complex; Scandinavian Caledonides; metamorphism; monazite geochronology; garnet;

   Sammanfattning : The Scandinavian Caledonides formed as a result of collision between the continents Baltica and Laurentia, in Silurian and Early Devonian time. The evolution of the orogen has been a topic of research since before the turn of the last century. LÄS MER

3. 7. Late Devonian vertebrates from Siberia: a synchrotron microtomography study of bone bed material

   Master-uppsats, Uppsala universitet/Institutionen för biologisk grundutbildning

   Författare :Étienne Fortier-Dubois; [2016]
   Nyckelord :Siberia; Late Devonian; Megistolepis; paleontology; microtomography; vertebrates; synchrotron; stem tetrapods; fossil;

   Sammanfattning : This is an investigation of new vertebrate fossil material from the Late Devonian locality of Ivanovka, Uryup River, Siberia. This bone bed material, circa 375 million years in age, represents a unique opportunity to fill a gap in our understanding of Late Devonian diversity, biogeography, and vertebrate evolution: Siberia, at the time, was an independent continent, and yet its fauna remains virtually unknown in comparison with the other paleocontinents, Euramerica and Gondwana. LÄS MER

4. 8. The Primitive Antiarch Yunnanolepis from China : A Microtomographic Study

   Kandidat-uppsats, Uppsala universitet/Paleobiologi

   Författare :Jessica Grahn; [2016]
   Nyckelord :placodermi; microtomography; 3D model; mikrotomografi; 3D-modell;

   Sammanfattning : Placoderms appeared in the Silurian period and rapidly evolved and dominated the waters during the Devonian period. Among the earliest of the placoderms are yunnanolepids, a primitive form of antiarch from the Early Devonian of China and Vietnam. LÄS MER

5. 9. Study of the Taxonomy and the Inter and Intra Specific Variability of Phacopidae from the Lower Devonian of Algeria: Morphometric Approach and Meaning.

   Master-uppsats, Uppsala universitet/Institutionen för geovetenskaper

   Författare :Gauthier Hainaut; [2015]
   Nyckelord :Paleontology; Trilobite; Devonian; Biometry; Morphometry; Covariance;

   Sammanfattning : An Algerian Phacopid fauna, described by Lemaître in 1952, is reexamined here. Species arereevaluated in order to be in agreement with modern taxonomy. To characterize the size and shape of our specimens, as well as inter- and intraspecific variations, a morphometric analysis was performed. Only holaspids were analyzed. LÄS MER

7. 10. Palaeoenvironments of the Earliest (Middle Devonian) Tetrapod Trackways from the Holy Cross Mountains, Poland; Locomotion in a Terrestrial Setting?

   Master-uppsats, Uppsala universitet/Institutionen för geovetenskaper

   Författare :Martin Qvarnström; [2015]
   Nyckelord :Tetrapods; palaeoenvironment; trackways; paleosols; microfacies; trace fossils; fin-limb transition; Holy Cross Mountains.;

   Sammanfattning : The palaeoenvironment from which early tetrapods emerged is crucial to comprehend in order to understand the mechanisms that drove and allowed the terrestrialization of vertebrates; one of the most important evolutionary ‘events’ in the history of animals. Nevertheless, much of the terrestrialization is shrouded in obscurity, inter alia, due to scarcity of early tetrapods in the fossil record. LÄS MER