Paleomagnetic results from rhyolites (Early Cretaceous?) and andesite dikes at two localities in the Ocana area, northern Santander Massif, Colombia
Published:January 01, 1984
R. B. Hargraves, R. Shagam, R. Vargas, G. I. Rodriguez, 1984. "Paleomagnetic results from rhyolites (Early Cretaceous?) and andesite dikes at two localities in the Ocana area, northern Santander Massif, Colombia", The Caribbean-South American Plate Boundary and Regional Tectonics, William E. Bonini, Robert B. Hargraves, Reginald Shagam
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The mean remanent magnetization vector of six samples from andesite dikes at one locality after 15 mT ODF is D = 309, I = +77, k = 13, α95 = 20. Five rhyolite samples from each of two sites at a second locality yield: 50 mT ODF, D = 194,1 = +30, k = 166, α95 = 6; 30 mT ODF D = 158,1 = +46, k = 101, α95 = 8. These rocks are probably of Mesozoic age and the magnetization appears primary; but the vectors are unlike those for the stable South American craton at any time during the Phanerozoic. These data suggest that complex tectonic rotations have occurred in at least this part of the Santander Massif.