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The Mesoproterozoic Single-Lid Tectonic Episode: Prelude to Modern Plate Tectonics Science Editor Openings for 2022

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The Mesoproterozoic Single-Lid Tectonic Episode: Prelude to Modern Plate Tectonics Science Editor Openings for 2022 Call for 2021 Annual Meeting Proposals VOL. 30, NO. 12 | DECEMBER 2020 The Mesoproterozoic Single-Lid Tectonic Episode: Prelude to Modern Plate Tectonics Science Editor Openings for 2022 GSA seeks applications for science co-editors for GSA Today, GSA Bulletin, Geosphere, and Geology (one position each). The four-year terms begin 1 January 2022. Duties include: ensuring stringent peer review and expeditious processing of manuscripts; making final acceptance or rejection decisions after considering reviewer recommendations; and, along with your co-editors, setting the editorial tone of the journal and maintaining excellent content through publication of a diverse range of papers. POSITION DETAILS REQUIRED QUALIFICATIONS GSA Today editors can expect to handle papers on a wide • Experience as an editor or associate editor for a range of topics, and editors are also responsible for solic- geoscience journal. Include details of the duties and iting submissions of papers they feel would be of interest duration of the position(s) held. to GSA members and other readers. Areas of expertise that best complement the continuing editor include, but • Demonstrated expertise in two or more fields in the are not limited to: surface geology; modern processes; cli- geosciences or in interdisciplinary fields broadly mate issues; environmental concerns. related to the geosciences. Geosphere editors should be broadly interdisciplinary with • Demonstrated experience handling a significant specialization in a range of possible disciplines, such as: editorial workload and ability to make timely decisions. volcanology; magmatism; igneous petrology; geochem- • Because of the breadth of topics covered in GSA istry; geochronology; sedimentary geology; stratigraphy; journals, the applicant must clearly express planetary geology; geoscience education. willingness to handle papers outside of their main disciplines. Research interests that complement those of the continu- ing GSA Bulletin editors include, but are not limited to: • Demonstrated ability to communicate clearly and be deformation; petrology; sedimentary geology; stratigraphy; responsive to author needs geochemistry; marine geology; neotectonics; planetary geology; Precambrian geology; tectonics; tectonophysics; high-T thermochronology. PREFERRED QUALIFICATIONS Geology editors should expect to handle 200–250 man- • Experience with a GSA journal as a reviewer, associate uscripts each year, with ~35 active manuscripts on any editor, or editor. given day. Research interests that complement those of the continuing editors include, but are not limited to: deforma- • Breadth of interdisciplinary experience to complement tion; geodynamics; petrology; Precambrian geology; that of existing editors; demonstrated interest in structural geology; tectonophysics; accessory minerals; interdisciplinary research. economic geology; geochemistry–high-T isotopes; high-T • International reputation and connections with the geochronology. geoscience communities. Editors work out of their current locations at work or at • Interest in encouraging innovation; willingness to take home. The positions are considered voluntary, but GSA risks. provides an annual stipend and funds for office expenses. • Ability to support a positive team dynamic; ability to Evaluation Process: The GSA Publications Committee work with GSA staff and other editors to enhance the will evaluate applications and make its recommendations reputation of the journal. to GSA Council based on the combination of how a can- didate’s disciplinary expertise fits with the needs of the journal and on the candidate’s application, which should provide documentation of the required and preferred qual- ifications listed here. GSA affirms the value of diverse scientific ideas and the connection between diverse scientific ideas and a diverse group of contributors of those ideas. Accordingly, GSA welcomes applications from all qualified persons and encourages applications that highlight diversity. To Apply: In a single PDF, submit your curriculum vitae and a letter of application that demonstrates how your interests and experience fulfill the required and preferred qualifi- cations listed below to Jeanette Hammann, jhammann@ geosociety.org. Deadline: 1 March 2021. DECEMBER 2020 | VOLUME 30, NUMBER 12 SCIENCE 4 The Mesoproterozoic Single-Lid Tectonic Episode: Prelude to Plate Tectonics GSA TODAY (ISSN 1052-5173 USPS 0456-530) prints news Robert J. Stern and information for more than 22,000 GSA member readers and subscribing libraries, with 11 monthly issues (March- Cover: Typical coarse-grained to pegmatitic, orthopyroxene-bearing April is a combined issue). GSA TODAY is published by The anorthosite (leuconorite) from the 1765–1630 Ma Mealy Mountains Intrusive Suite (Labrador, Geological Society of America® Inc. (GSA) with offices at 3300 Penrose Place, Boulder, Colorado, USA, and a mail- Canada). This Mesoproterozoic anorthosite massif intrudes the Mealy Mountains Terrane and is ing address of P.O. Box 9140, Boulder, CO 80301-9140, USA. one of several classic intrusive complexes in the Grenville Province of eastern North America. GSA provides this and other forums for the presentation The hammer is ~40 cm long. Photo courtesy of Grant Bybee, Univ. of the Witwatersrand. See of diverse opinions and positions by scientists worldwide, related article, p. 4–10. regardless of race, citizenship, gender, sexual orientation, religion, or political viewpoint. Opinions presented in this publication do not reflect official positions of the Society. © 2020 The Geological Society of America Inc. All rights reserved. Copyright not claimed on content prepared wholly by U.S. government employees within the scope of their employment. Individual scientists are hereby granted permission, without fees or request to GSA, to use a single 12 Call for Nominations: 2021 GSA Awards & Medals figure, table, and/or brief paragraph of text in subsequent work and to make/print unlimited copies of items in GSA TODAY for noncommercial use in classrooms to further 12 Call for GSA Fellowship Nominations education and science. In addition, an author has the right to use his or her article or a portion of the article in a thesis 13 2020–2021 Scientific Division Officers and Past Chairs or dissertation without requesting permission from GSA, provided the bibliographic citation and the GSA copyright credit line are given on the appropriate pages. For any 14 Scientists in Parks: A New Program for the Next Generation of Stewards other use, contact [email protected]. Subscriptions: GSA members: Contact GSA Sales & Service, 15 GeoCorps™ America: Explore Geoscience-Related Opportunities on America’s +1-888-443-4472; +1-303-357-1000 option 3; gsaservice@ Public Lands geosociety.org for information and/or to place a claim for non-receipt or damaged copies. Nonmembers and institutions: GSA TODAY is US$105/yr; to subscribe, or for claims for 16 2019–2020 GSA-USGS Congressional Science Fellow Final Report non-receipt and damaged copies, contact gsaservice@ geosociety.org. Claims are honored for one year; please allow sufficient delivery time for overseas copies. Peri- 17 Mentoring365 odicals postage paid at Boulder, Colorado, USA, and at additional mailing offices. Postmaster: Send address 18 GSA Graduate Student Research Grants changes to GSA Sales & Service, P.O. Box 9140, Boulder, CO 80301-9140. 18 Awards for Students to Attend GSA’s Northeastern Section Meeting GSA TODAY STAFF Executive Director and Publisher: Vicki S. McConnell 18 J. David Lowell Field Camp Scholarships Science Editors: Mihai N. Ducea, University of Arizona, Dept. of Geosciences, Gould-Simpson Building, 1040 E 4th 20 Geoscience Jobs & Opportunities Street, Tucson, Arizona 85721, USA, [email protected] .edu; Peter Copeland, University of Houston, Department of Earth and Atmospheric Sciences, Science & Research 23 GSA Publications Highlights: Share Your Research with the World. Publish Building 1, 3507 Cullen Blvd., Room 314, Houston, Texas with GSA. 77204-5008, USA, [email protected]. Managing Editor: Kristen “Kea” Giles, [email protected], 24 Groundwork: A Three-Dimensional, Virtual Tour of the Johnston Geology [email protected] Museum Graphics Production: Emily Levine, [email protected] Advertising Manager: Ann Crawford, 26 Groundwork: It’s Time to Defuse the Cambrian “Explosion” +1-800-472-1988 ext. 1053; +1-303-357-1053; Fax: +1-303-357-1070; [email protected] 28 GSA Foundation Update GSA Online: www.geosociety.org GSA TODAY: www.geosociety.org/gsatoday 29 2021 GSA Section Meetings Printed in the USA using pure soy inks. 30 Call for GSA-USGS Congressional Science Fellow 31 Call for Short Course and Technical Session Proposals: GSA 2021 Annual Meeting The Mesoproterozoic Single-Lid Tectonic Episode: Prelude to Modern Plate Tectonics Robert J. Stern, Geosciences Dept., The University of Texas at Dallas, Box 830688, Richardson, Texas 75083-0688, USA ABSTRACT 1. Active silicate bodies have convecting man- distributed volcanoes are buried and remelted The hypothesis that the Mesoproterozoic tles. Tectonics is the lithospheric expression a few kilometers below the surface. Venus (1600–1000 Ma) tectonic regime was a pro- of mantle convection. exhibits vigorous single-lid behavior domi- tracted single-lid episode is explored. Single- 2. Plate tectonics is lithosphere divided into a nated by mantle plumes and rifts (Ghail, lid tectonic regimes contrast with plate tec- mosaic of strong plates, which move on and 2015);
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