Sökning: "rhyolite"
Visar resultat 1 - 5 av 7 avhandlingar innehållade ordet rhyolite.
1. The dynamic emplacement of felsic magma in the upper crust
Sammanfattning : Felsic magma intrudes earth’s upper crust through a variety of mechanisms. Magma intrusion growth and shape have mainly been explained in terms of host rock properties and intrusion depth, while considering the magma as an overpressurised fluid. LÄS MER
2. Volcanology of the paleoproterozoic Maurliden area and its four unusual massive sulphide deposits, Skellefteå district, Sweden
Sammanfattning : The Skellefte district is one of three major ore provinces in Sweden and contains more than 85 Zn-Cu-Au-Ag massive sulphide deposits. The Maurliden area is situated in the central part of the district and is a subaqueous volcanic dominated area with four Zn-Pb-Cu-Au-Ag sulphide deposits. LÄS MER
3. Volcanic stratigraphy and hydrothermal alteration of the Petiknäs south Zn-Pb-Cu-Au-Ag volcanic-hosted massive sulfide deposit, Sweden
Sammanfattning : The Skellefte district is one of the most important mining regions in Sweden and Europe. The district contains more than 85 pyritic Zn-Cu-Au-Ag massive sulfide deposits. LÄS MER
4. Volcanic stratigraphy, chemical stratigraphy, and hydrothermal alteration of the Petiknäs South Volcanic-hosted massive sulfide deposit, Sweden
Sammanfattning : The main exploration methods which have been used in the Skellefte district are prospecting for ore boulders in young glacial deposits and electrical geophysical methods. The discovery of new ores which likely are located at deep levels (>200 m), requires improved exploration methods, which in turn require a better understanding of the geology and alteration patterns of the known VMS deposits. LÄS MER
5. Evolution of a silicic magma reservoir in the upper crust : Reyðarártindur pluton, Southeast Iceland
Sammanfattning : Field observations of extinct and exposed magma reservoirs shed light on processes operating in the roots of presently active volcanoes. The Reyðarártindur pluton, Southeast Iceland is an example of a fossil shallow magma reservoir that fed eruptions. LÄS MER