Abstract

This is the first palcomagnetic result from the Paleozoic Botwood Central Zone of Newfoundland. Two Lower Paleozoic rock units were sampled: the Botwood Group (rhyolite and red sandstone) at 16 sites and the Mount Peyton Batholith (dioritic and granitic phases) at 12 sites. Two phases are recognized in this intrusion: dioritic (420 Ma) and granitic (380 Ma). Four distinct magnetization directions were observed during the study. In the Lawrenceton Formation (Bot-wood Group, rhyolite) the direction obtained after tilt correction (180°, + 47°) gives a pole at 125°E, 13°N, probably of Lower Silurian age. The overlying Wig Wam Formation of the Botwood Group (red sandstone) was magnetized during a reversal. Detailed demagnetization techniques (thermal, chemical, and alternating field) were used to separate the normal and reversed directions in composite magnetizations; with a mean direction of 194°, + 28°, the pole (100°E, 25°N) obtained after tilt correction is related to a Silurian age. Two magnetizations were found in the Mount Peyton Batholith: the first one (pole at 68°E, 15°S) is associated with the dioritic phase with an age of 420 Ma. The second one (pole at 125°E, 63°S) is associated with the granitic phase at 380 Ma.

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