Paleomagnetic reexamination of the Lower Ordovician Wabana and Bell Island Groups of the Avalon Peninsula of Newfoundland

• Published in: Canadian Journal of Earth Sciences
• Main Authors: Buchan, K. L., Hodych, J. P.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Canadian Science Publishing 1982
• Subjects: Bell Island; Newfoundland
• Online Access: http://dx.doi.org/10.1139/e82-087; http://www.nrcresearchpress.com/doi/pdf/10.1139/e82-087

The Wabana and Bell Island Groups of the Avalon Peninsula of Newfoundland contain oolitic hematite beds of Early Ordovician age, dipping ~11° north-northwest. Twenty-one oolitic hematite samples from nine sites were thermally demagnetized in 10 or 11 steps to 660 or 680 °C. At 450 °C, 15 samples from six sites define a stable magnetization direction (D = 21.2°, I = −12.5°, k = 137, α 95 = 5.7°) with respect to bedding. The remaining six samples failed to attain the stable end-point, five of them because of growth of much "magnetite," which probably resulted from breakdown of siderite during thermal demagnetization.The paleopole for the Wabana – Bell Island Groups lies at 33°N 102°E (dm = 5.8°, dp = 3.0°). It is compared with other early Paleozoic paleopoles from cratonic North America and the Avalon zone, and its significance for the Iapetus Ocean is discussed.