Continental crust beneath southeast Iceland
نویسندگان
چکیده
منابع مشابه
Continental crust beneath southeast Iceland.
The magmatic activity (0-16 Ma) in Iceland is linked to a deep mantle plume that has been active for the past 62 My. Icelandic and northeast Atlantic basalts contain variable proportions of two enriched components, interpreted as recycled oceanic crust supplied by the plume, and subcontinental lithospheric mantle derived from the nearby continental margins. A restricted area in southeast Icelan...
متن کاملP-wave velocity structure of the crust and uppermost mantle beneath Iceland from local earthquake tomography
The structure of the crust and uppermost mantle beneath Iceland, the keys to understanding the magma plumbing system of the hotspot and hotspot–ridge interaction, was poorly constrained in previous seismological investigations. Here we develop a three-dimensional P-wave velocity model of the Icelandic crust and uppermost mantle from tomographic inversion of over 3500 first-arrivals from local e...
متن کاملArchaean zircons in Miocene oceanic hotspot rocks establish ancient continental crust beneath Mauritius
A fragment of continental crust has been postulated to underlie the young plume-related lavas of the Indian Ocean island of Mauritius based on the recovery of Proterozoic zircons from basaltic beach sands. Here we document the first U-Pb zircon ages recovered directly from 5.7 Ma Mauritian trachytic rocks. We identified concordant Archaean xenocrystic zircons ranging in age between 2.5 and 3.0 ...
متن کاملWhen the Continental Crust Melts
The continental crust is 41.4 km thick on average and covers 39% of the Earth’s surface. Information from the isotopic and trace element composition of >4-billion-yearold (Ga) zircon grains and the evolution of mantle isotopic reservoirs indicates that 75%, and possibly more, of the continental crust was created before 2.5 Ga (Harrison 2009; Belousova et al. 2010). Thus, the continental crust i...
متن کاملDifferentiation of the continental crust by relamination
a r t i c l e i n f o Crust extracted from the mantle in arcs is refined into continental crust in subduction zones. During sediment subduction, subduction erosion, arc subduction, and continent subduction, mafic rocks become eclogite and may sink into the mantle, whereas more silica-rich rocks are transformed into felsic gneisses that are less dense than peridotite but more dense than the uppe...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 2015
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.1423099112