Geological Society of London
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Provenance of Lower Cretaceous sediments in the Wandel Sea Basin, North Greenland

posted on 2016-06-21, 12:11 authored by T.S. RØhr, T. Andersen, H. Dypvik

Detrital zircons in Lower Cretaceous sedimentary formations from the Wandel Sea Basin (Kilen, Peary Land) were dated by U–Pb and analysed for Hf isotopes by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Samples from Kilen and Peary Land display a wide range of U–Pb ages, with significant zircon populations at 1.0–1.1 and 1.8–2.0 Ga. Major hiati occur between 2.1 and 2.4 and from 0.48 to 0.91 Ga. Low initial ϵHf values indicate that recycled crust components are significant in Caledonian-aged zircons, and in Palaeoproterozoic (1.8–2.0 Ga) and Neoarchaean zircon populations. Other U–Pb age populations in the studied samples are dominated by zircons with positive ϵHf values indicating a significant contribution of mantle-derived material in these periods. A narrow range of ϵHf values is commonly seen within a given U–Pb age population, and the values seen in the samples are in general correlated with the different age populations and their frequency. One exception is the 1.8–2.0 Ga population, where variations suggest variable sources. The U–Pb and Hf data are consistent with Greenland as the sole source of zircon from the studied sandstones.