Avancerad sökning
Hittade 5 avhandlingar som matchar ovanstående sökkriterier.
1. U-Pb dating of detrital zircon from the Mt. Alfred area, Yilgarn Craton, Western Australia
Sammanfattning : Hadean and Paleo-Eoarchean aged detrital zircon provide a rare glimpse into the nature of the early Earth. Thus, the characterisation of new localities with rocks that host Hadean and Paleo-Eoarchean zircon provide invaluable insight into the Earth’s early crust. LÄS MER
2. Silicic Magma Genesis in Basalt-dominated Oceanic Settings : Examples from Iceland and the Canary Islands
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
3. Magma generation and formation of continental crust in the Izu arc
Sammanfattning : The Izu oceanic arc is produced by the subduction of the Pacific Sea Plate beneath the Philippine Sea Plate. The proto-Izu oceanic arc was initially formed at ca. 50 Ma, then it was separated into the Kyushu-Palau and Izu arc by the extension of the Shikoku basin from ca. 25 Ma. LÄS MER
4. Assessing the reliability of detrital zircon in Early-Earth provenance studies
Sammanfattning : Our understanding of the Early Earth and the processes that have shaped its evolution have spawned predominantly from the geochemical and isotopic signatures of a small number of zircon populations around the world. Studies of trace element distributions, Hf and O isotope systematics as well as mineral inclusion chemistry in detrital zircon are combined with U-Pb chronology in order to constrain source rock characteristics. LÄS MER
5. Evolution of continental crust in the Proterozoic : growth and reworking in orogenic systems
Sammanfattning : To understand the growth of continental crust, the balance between juvenile mantle derived extraction, infracrustal reworking and crustal recycling, needs to be estimated. Since the beginning of the century, the use of coupled in situ zircon U–Pb, Lu–Hf and O isotope analyses as a tool to address these questions have increased exponentially. LÄS MER