Mesoproterozoic contractional orogeny in western North America: Evidence from ca. 1.4 Ga plutons

Research Article| October 01, 1994 Mesoproterozoic contractional orogeny in western North America: Evidence from ca. 1.4 Ga plutons M. W. Nyman; M. W. Nyman 1Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, New Mexico 87131 Search for other works by this author on: GSW Google Scholar K. E. Karlstrom; K. E. Karlstrom 1Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, New Mexico 87131 Search for other works by this author on: GSW Google Scholar E. Kirby; E. Kirby 1Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, New Mexico 87131 Search for other works by this author on: GSW Google Scholar C. M. Graubard C. M. Graubard 2Department of Geological Sciences, University of California, Santa Barbara, California 93106-9630 Search for other works by this author on: GSW Google Scholar Author and Article Information M. W. Nyman 1Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, New Mexico 87131 K. E. Karlstrom 1Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, New Mexico 87131 E. Kirby 1Department of Earth and Planetary Sciences, University of New Mexico, Albuquerque, New Mexico 87131 C. M. Graubard 2Department of Geological Sciences, University of California, Santa Barbara, California 93106-9630 Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1994) 22 (10): 901–904. https://doi.org/10.1130/0091-7613(1994)022<0901:MCOIWN>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 Email Permissions Search Site Citation M. W. Nyman, K. E. Karlstrom, E. Kirby, C. M. Graubard; Mesoproterozoic contractional orogeny in western North America: Evidence from ca. 1.4 Ga plutons. Geology 1994;; 22 (10): 901–904. doi: https://doi.org/10.1130/0091-7613(1994)022<0901:MCOIWN>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 Kinematic data from cogenetic dikes, magmatic foliation, and high-temperature solid-state deformation observed in 1.4 Ga plutons and their aureoles in the southwestern United States show a synmagmatic strain regime involving regional contraction. We propose that these plutons were preferentially emplaced along Paleoproterozoic shear zones and province boundaries. Thermal softening of the middle crust (8-12 km) during intrusion allowed regional strain and pluton-enhanced metamorphism to be recorded as much as 1500 km inboard of the southern margin of Laurentia. We abandon the term "anorogenic" and instead view these plutons as recording compressional or transpressional plate-margin tectonism from 1.5 to 1.3 Ga along southern Laurentia. Further study of 1.4 Ga plutons may also offer insights into middle-crustal processes that occur in broad zones of transpressional deformation. 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.