Title: Structure and emplacement history of a multiple-center, cone-sheet–bearing ring complex: The Zarza Intrusive Complex, Baja California, Mexico
Abstract: Research Article| April 01, 1999 Structure and emplacement history of a multiple-center, cone-sheet–bearing ring complex: The Zarza Intrusive Complex, Baja California, Mexico S. E. Johnson; S. E. Johnson 1Department of Earth and Planetary Sciences, Macquarie University, Sydney, New South Wales 2109, Australia2Departamento de Geología, CICESE, Km 107 Carratera, Ensenada-Tijuana, Baja California, México Search for other works by this author on: GSW Google Scholar S. R. Paterson; S. R. Paterson 3Department of Earth Sciences, University of Southern California, California 90089-0740 Search for other works by this author on: GSW Google Scholar M. C. Tate M. C. Tate 1Department of Earth and Planetary Sciences, Macquarie University, Sydney, New South Wales 2109, Australia Search for other works by this author on: GSW Google Scholar Author and Article Information S. E. Johnson 1Department of Earth and Planetary Sciences, Macquarie University, Sydney, New South Wales 2109, Australia2Departamento de Geología, CICESE, Km 107 Carratera, Ensenada-Tijuana, Baja California, México S. R. Paterson 3Department of Earth Sciences, University of Southern California, California 90089-0740 M. C. Tate 1Department of Earth and Planetary Sciences, Macquarie University, Sydney, New South Wales 2109, Australia Publisher: Geological Society of America First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (1999) 111 (4): 607–619. https://doi.org/10.1130/0016-7606(1999)111<0607:SAEHOA>2.3.CO;2 Article history First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation S. E. Johnson, S. R. Paterson, M. C. Tate; Structure and emplacement history of a multiple-center, cone-sheet–bearing ring complex: The Zarza Intrusive Complex, Baja California, Mexico. GSA Bulletin 1999;; 111 (4): 607–619. doi: https://doi.org/10.1130/0016-7606(1999)111<0607:SAEHOA>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 SocietyGSA Bulletin Search Advanced Search Abstract The Cretaceous Zarza Intrusive Complex, located in the Peninsular Ranges of Baja California Norte, Mexico, is perhaps the best-preserved multiple-center, cone-sheet–bearing ring complex documented in North America. The 7 km2 elliptical complex hosts three nested, non-concentric intrusive centers that are successively younger to the south. The northern and central centers show the same evolutionary sequence of (1) intrusion of concentric gabbroic cone sheets, (2) intrusion of massive core gabbros, and (3) development of subvertical, ductile ring faults. Ring-fault kinematics indicate that both centers moved down relative to the surrounding country rocks, suggesting collapse into an underlying magma chamber. The southern center is composed of approximately equal proportions of gabbro and tonalite and lacks cone sheets. Aluminum-in-hornblende barometry on the tonalite indicates a maximum emplacement depth of 2.3 ± 0.6 kbar. The Zarza Intrusive Complex is surrounded by a ductile deformation aureole, and bedding is inward dipping and inward younging around the entire complex. Excellent preservation of the intrusive history allowed us to evaluate the origin of the aureole, and the three most applicable models are (1) collapse of the complex into its underlying magma chamber, (2) sinking of the complex and its chamber after solidification, and (3) formation of the aureole prior to emplacement of the complex. The preserved structural and intrusive relationships provide information on the dynamic evolution of subvolcanic magma chambers and suggest that the complex may have been overlain by a caldera. 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.
Publication Year: 1999
Publication Date: 1999-04-01
Language: en
Type: article
Indexed In: ['crossref']
Access and Citation
Cited By Count: 64
AI Researcher Chatbot
Get quick answers to your questions about the article from our AI researcher chatbot