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Cretaceous and Tertiary sedimentary, magmatic, and tectonic evolution of north-central Sonora (Arizpe and Bacanuchi Quadrangles), northwest Mexico

2000; Geological Society of America; Volume: 112; Issue: 4 Linguagem: Inglês

10.1130/0016-7606(2000)112 2.0.co;2

1943-2674

Carlos M. González–León, W. C. McIntosh, Rufino Lozano-Santacruz, Martín Valencia-Moreno, Ricardo Amaya-Martínez, José Luis Rodríguez-Castañeda,

Rangeland and Wildlife Management

Research Article| April 01, 2000 Cretaceous and Tertiary sedimentary, magmatic, and tectonic evolution of north-central Sonora (Arizpe and Bacanuchi Quadrangles), northwest Mexico Carlos M. González León; Carlos M. González León 1Estación Regional del Noroeste, Instituto de Geología, Universidad Nacional Autónoma de México, Apartado Postal 1039, Hermosillo, Sonora, México 83000 Search for other works by this author on: GSW Google Scholar William C. McIntosh; William C. McIntosh 2New Mexico Geochronology Research Laboratory, New Mexico Institute of Mining and Technology, Socorro, New Mexico 87801, USA Search for other works by this author on: GSW Google Scholar Rufino Lozano-Santacruz; Rufino Lozano-Santacruz 3Instituto de Geología, Universidad Nacional Autónoma de México, Ciudad Universitaria, México, D.F. 04510 Search for other works by this author on: GSW Google Scholar Martin Valencia-Moreno; Martin Valencia-Moreno 4Department of Geosciences, University of Arizona, Tucson, Arizona 85721, USA Search for other works by this author on: GSW Google Scholar Ricardo Amaya-Martínez; Ricardo Amaya-Martínez 5Departamento de Geología, Universidad de Sonora, Hermosillo, Sonora, México 83000 Search for other works by this author on: GSW Google Scholar José Luis Rodríguez-Castañeda José Luis Rodríguez-Castañeda 1Estación Regional del Noroeste, Instituto de Geología, Universidad Nacional Autónoma de México, Apartado Postal 1039, Hermosillo, Sonora, México 83000 Search for other works by this author on: GSW Google Scholar Author and Article Information Carlos M. González León 1Estación Regional del Noroeste, Instituto de Geología, Universidad Nacional Autónoma de México, Apartado Postal 1039, Hermosillo, Sonora, México 83000 William C. McIntosh 2New Mexico Geochronology Research Laboratory, New Mexico Institute of Mining and Technology, Socorro, New Mexico 87801, USA Rufino Lozano-Santacruz 3Instituto de Geología, Universidad Nacional Autónoma de México, Ciudad Universitaria, México, D.F. 04510 Martin Valencia-Moreno 4Department of Geosciences, University of Arizona, Tucson, Arizona 85721, USA Ricardo Amaya-Martínez 5Departamento de Geología, Universidad de Sonora, Hermosillo, Sonora, México 83000 José Luis Rodríguez-Castañeda 1Estación Regional del Noroeste, Instituto de Geología, Universidad Nacional Autónoma de México, Apartado Postal 1039, Hermosillo, Sonora, México 83000 Publisher: Geological Society of America Received: 24 Jul 1997 Revision Received: 20 Jul 1999 Accepted: 27 Jul 1999 First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (2000) 112 (4): 600–610. https://doi.org/10.1130/0016-7606(2000)112 2.0.CO;2 Article history Received: 24 Jul 1997 Revision Received: 20 Jul 1999 Accepted: 27 Jul 1999 First Online: 01 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 Carlos M. González León, William C. McIntosh, Rufino Lozano-Santacruz, Martin Valencia-Moreno, Ricardo Amaya-Martínez, José Luis Rodríguez-Castañeda; Cretaceous and Tertiary sedimentary, magmatic, and tectonic evolution of north-central Sonora (Arizpe and Bacanuchi Quadrangles), northwest Mexico. GSA Bulletin 2000;; 112 (4): 600–610. doi: https://doi.org/10.1130/0016-7606(2000)112 2.0.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 Arizpe and Bacanuchi Quadrangles provide a geologic history representative of the north-central part of Sonora, where lithologies are dominated by late Mesozoic and Cenozoic igneous rocks. In this study, new geologic mapping, 40Ar/39Ar dating, and geochemical analyses have been combined to provide a stratigraphic framework for this area. Ten lithostratigraphic units and several igneous and tectonic events can be recognized. The oldest outcropping rocks are Lower Cretaceous strata of the Bisbee Group, which along with the Picacho conglomerate record a middle Cretaceous compressive tectonic event and associated sedimentation. Laramide igneous activity is widespread and represented by (1) highly altered andesitic flows and volcaniclastic rocks (Arroyo Alcaparros andesitic rocks) of late Campanian to Maastrichtian age, (2) less altered andesitic and dacitic flows (Cerro Las Jarillas volcanic rocks) of late Paleocene age, and the intrusive bodies of (3) Sierra El Manzanal granodiorite and (4) Rancho Vaquería quartz monzonite. The Sierra El Manzanal granodiorite was emplaced at ca. 68 Ma on the basis of a 40Ar/39Ar biotite age (67.97 ± 0.19 Ma) and cooled relatively rapidly according to less precise 40Ar/39Ar hornblende and K-feldspar ages from the same sample (64.8 ± 1.0 Ma and 62.8 ± 0.3 Ma, respectively). The Cerro Las Jarillas volcanic rocks are slightly younger (40Ar/39Ar biotite age of 58.67 ± 0.17 Ma). The Rancho Vaquería quartz monzonite was emplaced at ca. 57 Ma (40Ar/39Ar biotite age of 56.73 ± 0.14 Ma and a less precise 40Ar/39Ar hornblende age of 55.0 ± 0.7 Ma); a protracted cooling history of this pluton is indicated by the age spectrum of K-feldspar from the same sample. A probable magmatic lull and denudation seem to have occurred between middle and late Eocene time and probably until the early Oligocene. Subsequently, rhyolitic to mafic volcanism began close to late Oligocene time and lasted until the early Miocene. Felsic volcanism is represented by the Cerro Cebadéhuachi volcanic rocks, from which 40Ar/39Ar hornblende ages of 27.25 ± 0.09 and 27.32 ± 0.06 Ma and a biotite age of 26.97 ± 0.06 Ma were obtained at three different localities. The Mesa Pedregosa volcanic rocks represent the transition to younger, mafic volcanic activity that occurred during the late Oligocene, as indicated by a sanidine 40Ar/39Ar age of 25.48 ± 0.05 Ma. This late Oligocene and early Miocene magmatism was paired by two episodes of extensional deformation. The first phase is characterized by northwest-striking normal faults and folds, which expose the deepest structural levels of the area, and by the related basin fill, the Bacanuchi conglomerate. The second phase is represented by north-striking normal faults and by the syntectonic basin fill, the Arizpe conglomerate. Basaltic andesite volcanic flows at the base of the Arizpe conglomerate yielded 40Ar/39Ar (whole-rock) ages of 23.52 ± 0.17 and 21 ± 0.20 Ma. The extensional deformation (27 to 23 Ma) in the study area is coeval with the development of metamorphic core complexes in neighboring areas of Sonora and with the onset of extension in southern Sonora. The mafic volcanic rocks and clastic sedimentary units associated with this extension resemble the basin fills that in other parts of Sonora are assigned to the Báucarit Formation.Geochemical information from samples representing each of the igneous events displayed high-K calc-alkalic and mostly metaluminous compositions. The older units including the Arroyo Alcaparros andesitic rocks, the Cerro Las Jarillas volcanic rocks, the Sierra El Manzanal granodiorite, and the Rancho Vaquería quartz monzonite are characterized by steep chondrite-normalized REE (rare earth element) slopes and generally well-developed negative Eu anomalies, suggesting garnet and plagioclase removal in the source. The younger igneous events including the Cerro Cebadéhuachi and Mesa Pedregosa volcanic rocks, and the basaltic flows associated with the Arizpe conglomerate, showed basin-shaped REE slopes with no Eu anomalies, suggesting clinopyroxene or amphibole fractionation. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.