Sr-Nd-Hf-Pb isotope and trace element geochemistry of the Natkusiak Formation continental flood basalts of the Neoproterozoic Franklin large igneous province, Victoria Island, Canada ...
The Neoproterozoic (ca. 723 Ma) Franklin large igneous province (LIP) located on Victoria Island, Arctic Canada, consists of the Natkusiak Formation continental flood basalts and a sill-dominated feeder system exposed in the Minto Inlier. The Franklin LIP is temporally linked with the breakup of Lau...
Main Author: | |
---|---|
Format: | Text |
Language: | English |
Published: |
University of British Columbia
2012
|
Subjects: | |
Online Access: | https://dx.doi.org/10.14288/1.0053555 https://doi.library.ubc.ca/10.14288/1.0053555 |
Summary: | The Neoproterozoic (ca. 723 Ma) Franklin large igneous province (LIP) located on Victoria Island, Arctic Canada, consists of the Natkusiak Formation continental flood basalts and a sill-dominated feeder system exposed in the Minto Inlier. The Franklin LIP is temporally linked with the breakup of Laurentia from Siberia and the Sturtian glaciation or “Snowball Earth”. Recent mapping shows that the Natkusiak Formation, preserved in two lobes (northern and southern), has a thin basal unit, ~50 m thick, followed by two ~500 m thick cycles (1 and 2) of basaltic sheet-flows. Sr-Nd-Pb-Hf isotopic compositions, major element oxides, and trace element concentrations of the Natkusiak basalts allow for the characterization of mantle source components and the extent of crustal contamination. Four geochemical groups (southern low- and high-Ti basalts; northern low- and high-Ti basalts) are defined. The basal basalts (low-Ti, 1.0-1.2 wt.% TiO₂) are distinguished from the overlying cycle 1 and 2 basalts (high-Ti, 1.2-1.8 ... |
---|