Evolution of continental crust in the Central Andes; constraints from Nd isotope systematics

Research Article| July 01, 1989 Evolution of continental crust in the Central Andes; constraints from Nd isotope systematics J. F. Miller; J. F. Miller 1Department of Earth Sciences, The Open University, Walton Hall, Milton Keynes MK7 6AA, England Search for other works by this author on: GSW Google Scholar N.B.W. Harris N.B.W. Harris 1Department of Earth Sciences, The Open University, Walton Hall, Milton Keynes MK7 6AA, England Search for other works by this author on: GSW Google Scholar Geology (1989) 17 (7): 615–617. https://doi.org/10.1130/0091-7613(1989)017<0615:EOCCIT>2.3.CO;2 Article history first online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation J. F. Miller, N.B.W. Harris; Evolution of continental crust in the Central Andes; constraints from Nd isotope systematics. Geology 1989;; 17 (7): 615–617. doi: https://doi.org/10.1130/0091-7613(1989)017<0615:EOCCIT>2.3.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract Periods of crustal reworking and of crustal growth can be distinguished within orogenic belts through Nd isotope studies of both igneous and sedimentary samples. The active continental margin of the Central Andes has been the site of magma genesis since at least 300 Ma.During the late Paleozoic, orogenesis was virtually an intracrustal reworking event, resulting in Late Proterozoic Nd model ages. During the Jurassic, a marked decrease in model age indicates a critical change in tectonic style and the onset of crustal growth. Younger model Nd ages are restricted to the 180-30 m.y. period of Andean tectonics consistent with active crustal growth through mantle input. Over the past 30 m.y., elevated model Nd ages from volcanics and sediments record a return to intracrustal processes in the Central Andes, synchronous with Tertiary crustal thickening. These results imply that crustal growth is not a continuous process at active continental margins and may progressively decelerate during orogenic evolution. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.