Sökning: "oceanic island"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden oceanic island.

  1. 1. 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

  3. 2. Silicic Magma Genesis in Basalt-dominated Oceanic Settings : Examples from Iceland and the Canary Islands

    Författare :Sylvia E. Berg; Valentin Troll; Steffi Burchardt; Frances Deegan; Morten Riishuus; Nicholas Arndt; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Silicic magmatism; Iceland; magma-crust interaction; proto-continental crust; early Earth; zircon geochronology and geochemistry; oxygen isotopes; 2011-2012 El Hierro eruption; crustal xenoliths; 3D X-ray μ-CT; volatiles; Geovetenskap med inriktning mot mineralogi; petrologi och tektonik; Earth Science with specialization in Mineral Chemistry; Petrology and Tectonics;

    Sammanfattning : The origin of silicic magma in basalt-dominated oceanic settings is fundamental to our understanding of magmatic processes and formation of the earliest continental crust. Particularly significant is magma-crust interaction that can modify the composition of magma and the dynamics of volcanism. LÄS MER

  4. 3. Tectonics of the middle Ural

    Författare :Magnus Friberg; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Earth sciences; Geovetenskap; Earth sciences; Geovetenskap; Geofysik med inriktning mot seismologi; Geophysics with specialization in Seismology;

    Sammanfattning : This thesis concerns the crustal structure and tectonic evolution of the Middle Urals. Theresults are based on near-vertical reflection seismic profiling, geological fieldobservations and single zircon geochronology,The Ural Mountains delimit. the eastern margin of Baltica. Prior to PalaeozoicUralian orogeny, this margin was bounded by an ocean. LÄS MER

  5. 4. GPS Measurements of Atmospheric Water Vapour in a Low-Latitude Region

    Författare :Surat Pramualsakdikul; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Signals at radio frequencies are distorted while travelling from a constellation of GPS satellites through the atmosphere. These signals can be used to estimate the amount of integrated precipitable water vapour (IPWV).There are advantages over other conventional techniques in terms of temporal and spatial resolution. LÄS MER

  7. 5. On Speciation in Birds – Genomic Signatures across Space and Time

    Författare :Martin Stervander; MEMEG; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; colonization; islands; isolation; introgressive hybridization; sympatry; natural selection; bill morphology; coalescence-based analyses; DNA sequencing; birds; divergence; Speciation;

    Sammanfattning : The process of speciation is a cornerstone in evolutionary biology. In Darwin’s On the Origin of Species, he described how he imagined that a new species would evolve to fill an empty niche. This focus on ecology shifted with Mayr towards the importance of isolation, and for many decades the geographic modes of speciation were debated. LÄS MER