Detrital zircon geochronology of Palaeozoic Novaya Zemlya – a key to understanding the basement of the Barents Shelf

• The Novaya Zemlya fold-and-thrust-belt is the northern con- tinuation of the late Palaeozoic Uralide Orogen. Little is known about its deeper structure and the basement history of the adjacent Barents and Kara shelves. Based on geological evidence and detrital zircon analysis of 28 samples from the northeastern and stratigraphically deepest part of the archi- pelago, we demonstrate that Cambro-Ordovician turbidite- dominated deposition was almost exclusively sourced from rocks consolidated during the Timanian orogeny (Timanian basement). A profound change in provenance occurred near the end of the Ordovician. Over 90% of the zircons from Silu- rian and about 80% from Devonian strata have ages charac- teristic of the Sveconorwegian Orogen, implying uplift of these rocks in the vicinity of Novaya Zemlya. The presence of Sveconorwegian and Grenvillian rocks in the high Arctic sug- gests revision of recent reconstructions of the Rodinia super- continent, its break-up and subsequent Caledonian orogeny.

Ämnesord

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Geologi (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Geology (hsv//eng)

Nyckelord

Novaya Zemlya

geochronology

zircons

detritus

Paleozoic

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)