Sökning: "Rb-Sr"

Hittade 5 avhandlingar innehållade ordet Rb-Sr.

  1. 1. The metamorphic history of Naxos (central Cyclades, Greece) : Deciphering the Oligocene and Miocene exhumation events

    Författare :Alexandre Peillod; Uwe Ring; Alasdair Skelton; Arne Willner; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Cycladic Blueschist Unit; exhumation; fluid flow; geothermobarometry; Hellenide orogen; Rb-Sr dating; subduction-zone metamorphism; Heat flow; Lower crust; extensional domain; Metamorphic core complex; Geology; geologi;

    Sammanfattning : High pressure, low temperature (HP-LT) rocks observed at the surface of the Earth are evidence ofpast subduction zones. Understanding the tectonics processes that control the exhumation of HP-LT metamorphic rocks in these subduction zones requires full comprehension of the pressure-temperature-time (P–T–t) cycle that the rocks experienced. LÄS MER

  3. 2. Constraining the timing of veins, faults and fractures in crystalline rocks by in situ Rb-Sr geochronology

    Författare :Mikael Tillberg; Henrik Drake; Mats E. Åström; Thomas Zack; Johan Hogmalm; Bjarne Almqvist; Linnéuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; geochronology; brittle deformation; crustal fluids; mineral precipitation; ancient microbial activity; Precambrian craton; Scandinavia; Natural Science; Naturvetenskap;

    Sammanfattning : Precambrian cratons are continent cores archiving the oldest crustal histories on Earth. The crystalline basement of cratons is typically characterized by complex arrays of multiple fracture and fault generations hosting minerals formed by fluids flowing through fracture networks. LÄS MER

  4. 3. The interpretation of the Rb-Sr and K-Ar ages of late Precambrian rocks in south-western Sweden

    Författare :Torbjörn Skiöld; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : .... LÄS MER

  5. 4. Disturbance of Pb, Sr, and Nd isotope systems related to medium and low grade metamorphism illustrated with data from the polymetamorphic Early Proterozoic (Rombak) - Sjangeli basement window of the Caledonides of Northern Sweden

    Författare :Rolf Romer; Luleå tekniska universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Applied Geology; Tillämpad geologi;

    Sammanfattning : The Sjangeli supracrustal belt forms the easternmost belt of a series approximately N-S striking, steeply dipping Early Proterozoic belts of the Rombak-Sjangeli basement window, which formed in an island arc setting. The volcanic units of the Sjangeli area consist of metatuffs, which contain abundant Cu-mineralizations, metalava flows and pillowed metalavas and are intercalated with banded carbonatesilicate rocks and micaschists, which contain various amounts of volcanic material. LÄS MER

  7. 5. Isotope enrichment by countercurrent electromigration in molten salts

    Författare :Arnold Lundén; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : A series of isotope enrichments by electromigration in molten saltslias been carried out during the last, years. The running conditions aresummarized in table 1 and the enrichments achieved are given intables 2—13. Practical details such as the arrangement of the electricalcircuits and the construction of the separation columns are discussed. LÄS MER