Search for dissertations about: "Lockne"

Found 5 swedish dissertations containing the word Lockne.

  2. 1. Late Ordovician Faunal Distribution and Ecospace Partitioning in Marine Impact Craters : The Aftermath of the Lockne and Tvären Events

    Author : Åsa M Frisk; Lars Holmer; Jan Ove Ebbestad; Maurits Lindström; Alan Owen; Uppsala universitet; []
    Keywords : impact crater; Lockne; Tvären; ecospace; the Great Ordovician Biodiversification Event; NATURAL SCIENCES; NATURVETENSKAP;

    Abstract : In the Middle to Late Ordovician a boost of marine biodiversity occurred which is regarded as the most rapid diversity in Earth’s history, and termed the Great Ordovician Biodiversification Event. This time is also unique in that at least four marine meteorite craters with a good record of post-impact sediments are preserved in Baltoscandia. READ MORE

  4. 2. The origin of the marine Lockne impact structure, Jämtland

    Author : Erik Sturkell; Christian Keoberl; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Lockne; Jämtland; Earth sciences; Geovetenskap; allmän och historisk geologi; General and Historical Geology;

    Abstract : The Lockne impact structure in Jämtland (63o00'20"N, 14o49'30"E), formed in the Middle Ordovician at approximately 455 Ma. The structure is a concentric crater with a total diameter of 13.5 km. The impact took place in a marine environment. READ MORE

  5. 3. Post-impact sediments in the Lockne and Tvären craters, Sweden: facies distribution and gastropod-like molluscs

    Author : Åsa Frisk; Uppsala universitet; []
    Keywords : ;

    Abstract : .... READ MORE

  6. 4. Investigation of the correlation of fracture frequency and electric resistivity in impact craters in crystalline rocks

    Author : Ann Bäckström; KTH; []
    Keywords : Electric resistivity; Fracture frequency; Impact generated fractures; Electro-magnetic techniques; VLF-R method; MT method; Window-mapping technique; Three-dimensional fracture calculations; heat-exchange structure; geothermal energy;

    Abstract : Impact craters are formed when a large meteorite or comethits the Earth. At the impact a shock wave is released causingabundant fracturing in the surrounding bedrock. This type offracturing is intense and occurs throughout a very large volume(>100 km3) of the bedrock. READ MORE

  7. 5. Traces in Earth's geological record of the break-up of the L-chondrite parent body 470 Ma

    Author : Carl Alwmark; Berggrundsgeologi; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; L chondrite; Middle Ordovician; extraterrestrial material; meteorite flux; Sweden;

    Abstract : This thesis deals with signatures in sediments on Earth related to the L-chondrite parent body break-up event at 470 Ma. The aim of this thesis is twofold: (1) investigate if the increased flux of extraterrestrial material to Earth, following the disruption of the L-chondrite parent body included larger, asteroid-sized bodies (2) try to develop new methods and tools for finding and classifying relict cosmic material in sediments. READ MORE