Open AccessThermochronologic constraints on the origin of the Great Unconformity
Author(s) -
Kalin T. McDannell,
C. Brenhin Keller,
William R. Guenthner,
Peter K. Zeitler,
David L. Shuster
Publication year - 2022
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.2118682119
Subject(s) - geology , unconformity , thermochronology , snowball earth , paleontology , diachronous , glacial period , supercontinent , tectonics , rodinia , earth science , craton
Significance The Great Unconformity involves a common gap of hundreds of millions to billions of years in the geologic record. The cause of this missing time has long eluded explanation, but recently two opposing hypotheses claim either a glacial or a plate tectonic origin in the Neoproterozoic. We provide thermochronologic evidence of rock cooling and multiple kilometers of exhumation in the Cryogenian Period in support of a glacial origin for erosion contributing to the composite basement nonconformity found across the North American interior. The broad synchronicity of this cooling signal at the continental scale can only be readily explained by glacial denudation.