11 research outputs found
Chemostratigraphy of the lower Bambuí Group, southwestern São Francisco Craton, Brazil: insights on Gondwana paleoenvironments
Correlation of Ordovician diamictites from Argentina and South Africa using detrital zircon dating
<p>The results of detrital zircon U–Pb geochronology suggest a maximum depositional age of 485 ± 7.2 Ma for a glacial diamictite
from the Sierra del Volcán in eastern Argentina (Tandilia System). Earlier interpretations associated the deposit with the
Neoproterozoic ‘snowball Earth' hypothesis. The data allow direct correlation, for the first time, between Early Palaeozoic
deposits in both South America and South Africa connecting the glacial deposits from southern Bolivia to central Argentina
with those in South Africa (Pakhuis Formation). On the basis of these results, a new distribution map of glacial cover, corresponding
to the Hirnantian stage, can be developed.
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