DOCSLIB.ORG

Sevier Orogeny

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Sevier Orogeny ~85 Ma Sevier orogeny Classic “Andean margin” Arc -arc -fold-and-thrust -foredeep 100 km Jones et al., Figure 2a Jones et al., Geosphere 2011 ~80 Ma Sevier orogeny Classic “Andean margin” fading Arc -arc dying Sierra Nevada, Mojave?, Penninsular Ranges -fold-and-thrust stops, southern Nevada -foredeep broadens ? Farallon A34-32o (84-73 Ma) Jones et al., Figure 2b Jones et al., Geosphere 2011 ~75 Ma Sevier/Laramide Arc? orogeny Classic “Andean margin” disrupted -arc dead Sierra Nevada, Nevada -arc? in Mojave; eastward in Mexico -fold-and-thrust stops, southern Nevada -foreland deformation starts -foredeep nearly gone, sedimentation sweeps to east Farallon A34-32o (84-73 Ma) Arc? Jones et al., Figure 2c Jones et al., Geosphere 2011 ~70 Ma Laramide orogeny Arc? -limited volcanism in west typically peraluminous (crustal melts?) -Colorado Mineral Belt established -fold-and-thrust stops, southern Nevada-Arizona -foreland deformation substantial -foredeep limited, COMB sedimentation focused to east 100 km Farallon A32-30o (73-67 Ma) Arc? Jones et al., Figure 2d Jones et al., Geosphere 2011 ~65 Ma Laramide orogeny Arc? -limited volcanism in west typically peraluminous (crustal melts?) -Colorado Mineral Belt active -fold-and-thrust stops, southern Nevada-Arizona -foreland deformation well- defined -thrust-belt foredeep absent, COMB sedimentation focused in Ireteba pluton local basins 100 km Farallon A30-27 (67-62 Ma) Arc Jones et al., Figure 2e Jones et al., Geosphere 2011 Torsvik et al., G^3, 2019 Henderson et al.' Farallon Aseismic Ridges, Laramide Orogeny lP5 J• Y -/1 Present•A-%=.- !,-,.•Hlsex ,--"•• _Hess • 0 • • • 30•N ••', •awaiian' %•-- •?. OøN , •-,• ;.%Hotspot Z• • • . -.•;•' :•_COcOs • O'N:• •..- + % + '•Hotspot ••• - OøN • ' Wilkes- - • ' ' Hotspot 180•W 90•W 180øW 90'W (b) 154 Ma Chron M21 30'N 30øN • Farallon Izanagi •% O'N OøN / Pacific 180:'W 90'W , , (f) 123 Ma Chron M 1 56Ma Kula/ -.,,'• 30øN 30øN Chron•""'••••2 • , "' Izanagi• Farallon Pacifi O'N OøN / Pacific + •'•'•'•'-":'?:'•' ';•';"•••'.•,• Farallon 180øW 90øW 180øW 90øW Fig. 3. Reconstructions of the lithospheric plates with Hendersonrespect to etthe al., Tectonics, 1984 hot spots, and formation of hot spot-produced volcanic edifices on the Pacific and Farallon plates at the spreading ridge. Hot spots are held fixed and the oceanic and continental plates are moved with respect to the hot spots from 154 Ma to 56 Ma. Large symbols show locations of the active hot spots in each frame, heavy lines show the tracks left on the oceanic plates by their motion over the hot spots. The large symbols are solid when the hot spots were located on the Pacific plate and open when the hot spots were located on the Kula plate. (a) The present location of the Lynn Seamount hot spot, the Wilkes hot spot, and the Hawaiian hot spot on the Pacific plate. (b)-(f) Reconstructions of plates, continents, and aseismic ridges. Locations of aseismic ridges showu subducted beneath North America are uncorrected for the dip of the slab. Barbed line marks the trench axis. Very heavy lines mark the ridge axes. This is a Mercator projection. NATURE GEOSCIENCE DOI: 10.1038/NGEO829 LETTERS A’ SNB: Sierra Nevada batholith 223 270 Fig. 3 SCB: Southern California batholith 315 section line PRB: Peninsular Ranges batholith Approximate location of trench 68 belt thrust SNB 72 evier Active margin S Strike-slip 79 zone 1 134 Intra-arc 76 ductile shear belts Shallow flat Colorado subduction 80 Approximate trace Plateau of San Andreas fault /Gulf of California 84 179 223 Early Palaeogene Sierra Madre Occidental arc SCB 223 Late Cretaceous eastern 88 batholitic belt Early Cretaceous western batholithic belt 179 Cretaceous to Early Tertiary forearc basin 55 A Franciscan subduction Farallon complex plate Laramide foreland 60 Late Cretaceous/Early Palaeogene 134 dextral transpression of Front Ranges belt 223 Late Cretaceous/Early Palaeogene 65 normal shortening of Wyoming belts PRB Early Palaeogene mainly thin-skinned (km) thrusting of Mexican belt 0100 200 300 400 Position of main Centre of putative Isotherms (¬40 °C): putative conjugates conjugates through time (Myr BP) 179 80 Myr BP slab contour at given depth (in km) Shatsky at 80 Myr BP 80 Shatsky Liu et al., Nature Geosc, 2010 Hess at 60 Myr BP 60 Hess 179 60 Myr BP slab contour at given depth (in km) Figure 2 Palinspastic map showing the southwest Cordilleran active margin and the Laramide foreland for the end of Cretaceous time3 with the | temperature field overlain. Contours (same as Fig. 1; light blue for 80 Myr BP, red for 60 Myr BP) and predicted positions of the putative Shatsky and Hess conjugate plateaux (inside the 179 km contour) are from the inverse model. Filled circles represent the volumetric centre of the putative Shatsky (light blue) and Hess (red) conjugate plateaux at given age during their subduction beneath North America. Line AA0 indicates the surface trace of the cross-sections shown in Fig. 3. these areas (Fig. 3a,b). Collectively, our study suggests that initial subducting Inca plateau in Peru23, where broad surface subsidence subduction of the plateau should have caused the slab to flatten is observed above the flat slab (Supplementary S2). because of the extra buoyancy associated with its thick crust, Laramide uplifts, at local scales, initiated along thrust faults but continuing flattening would mostly result from the increased during flat-slab underplating11 (Fig. 2). Subsequent regional-scale plate coupling with a possibly weakened mantle wedge21. As uplifts, however, are associated with removal of the plateau from the Shatsky conjugate translated beneath the Colorado Plateau beneath the Laramide province. The flat-slab associated with the region (Fig. 2), the oceanic crust is deep enough to undergo the Shatsky conjugate gradually sank deeper into the mantle as it basalt–eclogite phase transformation, during which the plateau migrated to the northeast. Both horizontal removal of flat slab loses its positive buoyancy22. Both the overall negative slab density from beneath the Colorado Plateau region after 80 Myr bp and anomaly and enhanced plate coupling during shallow subduction the overall diminishing negative dynamic topography associated drag the surface downward (Fig. 3a). A present-day analogy is the with cold slabs (Fig. 3b,c) led the surface to rebound in a NATURE GEOSCIENCE ADVANCE ONLINE PUBLICATION www.nature.com/naturegeoscience 3 | | 542 W.A. Yonkee, A.B. Weil / Earth-Science Reviews 150 (2015) 531–593 Yonkee & Weil, Earth Sci Rev, 2015 Fig. 6. Schematic lithospheric cross sections, shown for: A — Late Jurassic (~150 Ma); B — Early Cretaceous (~100 Ma); C — Late Cretaceous (~80 Ma); and D — Paleogene (~50 Ma) times. The Late Jurassic was marked by development of an E-dipping subduction zone, increased igneous activity along the magmatic arc, and initial shortening in the western part of the orogenic system. The Early Cretaceous included development of an accretionary complex, growth of the magmatic arc, crustal thickening in the hinterland, thin-skin shortening of the western Sevier belt, and sedimentation within a foreland basin. The Late Cretaceous included decreasing subduction angle (along with early development of a flat-slab segment to the south), a flare-up followed by shutdown of the magmatic arc, lower crustal thickening beneath a hinterland plateau, shortening in the eastern Sevier belt, and broad dynamic subsidence of the Western Interior Seaway. The Paleogene included rapid subduction and NE-underthrusting of the flat-slab segment, minor extension in the thickened hinterland, final shortening in the eastern Sevier belt, and uplift of Laramide arches that disrupted the foreland basin. zircon and geochemical signatures compared to temporally correlative coarser volcaniclastics with maximum depositional ages as young as forearc strata of the Great Valley Group, with Early Cretaceous sediment 123 Ma, which underwent blueschist metamorphism at 117 Ma. The sources mostly from accreted terranes and Jurassic volcanics, and Late Yolla Bolly terrane consists mostly of clastics with maximum deposi- Cretaceous sources mostly from more deeply eroded parts of the tional ages of ~120–110 Ma, along with a slab of ~170 Ma oceanic basalt magmatic arc (Dumitru et al., 2015). and chert, which underwent lower blueschist metamorphism at The eastern belt includes from east to west, the South Fork Mountain ~110 Ma (Dumitru et al., 2010, 2015). Limited accretion prior to schist, Valentine Formation, and Yolla Bolly terrane. The eastern belt 125 Ma may reflect thin trench fill during early arc growth, whereas was juxtaposed against the structurally overlying Coast Range ophiolite rapid accretion after ~125 Ma appears associated with thicker trench and Great Valley Group of the forearc basin along the Coast Range fault fill derived from the growing arc. The central belt consists mostly of mé- zone, which is interpreted to have initiated along the subduction zone at lange comprised of disrupted volcaniclastic mudstone, sandstone, and ~160 Ma and been subsequently reactivated as a normal fault that exotic blocks, which likely formed by a combination of sedimentary helped exhume the accretionary complex and generate accommodation (Wakabayashi, 2015) and tectonic (Cloos, 1982)processes,andsubse- space for deposition of forearc strata (Unruh et al., 2007; Ernst, 2011). quently underwent low-grade metamorphism. Strata contain rare Late Protoliths of the South Fork Mountain schist include ~135 Ma oceanic Cretaceous fossils and have DZ maximum
Load more

Recommended publications
  • The Tectonic Evolution of the Madrean Archipelago and Its Impact on the Geoecology of the Sky Islands
    The Tectonic Evolution of the Madrean Archipelago and Its Impact on the Geoecology of the Sky Islands David Coblentz Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM Abstract—While the unique geographic location of the Sky Islands is well recognized as a primary factor for the elevated biodiversity of the region, its unique tectonic history is often overlooked. The mixing of tectonic environments is an important supplement to the mixing of flora and faunal regimes in contributing to the biodiversity of the Madrean Archipelago. The Sky Islands region is located near the actively deforming plate margin of the Western United States that has seen active and diverse tectonics spanning more than 300 million years, many aspects of which are preserved in the present-day geology. This tectonic history has played a fundamental role in the development and nature of the topography, bedrock geology, and soil distribution through the region that in turn are important factors for understanding the biodiversity. Consideration of the geologic and tectonic history of the Sky Islands also provides important insights into the “deep time” factors contributing to present-day biodiversity that fall outside the normal realm of human perception. in the North American Cordillera between the Sierra Madre Introduction Occidental and the Colorado Plateau – Southern Rocky The “Sky Island” region of the Madrean Archipelago (lo- Mountains (figure 1). This part of the Cordillera has been cre- cated between the northern Sierra Madre Occidental in Mexico ated by the interactions between the Pacific, North American, and the Colorado Plateau/Rocky Mountains in the Southwest- Farallon (now entirely subducted under North America) and ern United States) is an area of exceptional biodiversity and has Juan de Fuca plates and is rich in geology features, including become an important study area for geoecology, biology, and major plateaus (The Colorado Plateau), large elevated areas conservation management.
    [Show full text]
  • G17 Laramide and Sevier Orogenies
    PLATE TECTONICS 423 g17 Laramide and Sevier orogenies < cratonal uplifts, thin-skinned thrust tectonics > ... mountains were thought of ... as punishments dealt to Earth by a Creator disappointed at the misbehavior of its inhabitants. This “catastrophist” view affected ... 18th and early 19th centuries, well-born ladies making the Grand Tour in Europe would pull down their window shades to avoid viewing the Alps. —Donald Kennedy.1 The fold-thrust belt of the northern Rocky Mountains is a back-arc east of the Cascade volcanic- mountains and sediment-filled trench of the eastward subducting Juan da Fuca oceanic plate. The central Rocky Mountains is earthquake-active. Its scenery is of a maturely dissected broad-uparch that in erosional section and by exhumation exposes features of the once Laramide mountain chain. The Wyoming Basin and southern Rocky Mountains is a region of reactivated Laramide cratonal uplifts. To the west of the southern Rocky Mountains and Colorado Plateau is the Basin and Range physiographic province. Its graben and horst scenery results from ongoing extension that has doubled the width of the region since the middle Cenozoic. Created are large displacements on listric faults that at their surfacing ends are imbricate normal faulted. This mimics in reverse the geometry produced by a former compressive orogeny called the Sevier.2 Laramide orogeny (Paleocene climax, near the end of the Cretaceous inception.) Laramide refers to ore-producing intrusions (as Boulder batholith, Montana), eastward-shed foreland- basin sediments as the E-K boundary containing undeformed Arapahoe Conglomerate fm and the folded Cretaceous Mesa Verde fm, Colorado.3 These strata are disconformable on Late Cretaceous Interior Seaway Laramic fm that is nonconformable on a Precambrian basement complex Laramide folds and faults resulted from block faulting and thrust faulting of this underlying craton.
    [Show full text]
  • Geological Society of America Bulletin
    Downloaded from gsabulletin.gsapubs.org on January 26, 2010 Geological Society of America Bulletin Sevier Orogenic Belt in Nevada and Utah RICHARD LEE ARMSTRONG Geological Society of America Bulletin 1968;79;429-458 doi: 10.1130/0016-7606(1968)79[429:SOBINA]2.0.CO;2 Email alerting services click www.gsapubs.org/cgi/alerts to receive free e-mail alerts when new articles cite this article Subscribe click www.gsapubs.org/subscriptions/ to subscribe to Geological Society of America Bulletin Permission request click http://www.geosociety.org/pubs/copyrt.htm#gsa to contact GSA Copyright not claimed on content prepared wholly by U.S. government employees within scope of their employment. Individual scientists are hereby granted permission, without fees or further requests to GSA, to use a single figure, a single table, and/or a brief paragraph of text in subsequent works and to make unlimited copies of items in GSA's journals for noncommercial use in classrooms to further education and science. This file may not be posted to any Web site, but authors may post the abstracts only of their articles on their own or their organization's Web site providing the posting includes a reference to the article's full citation. GSA provides this and other forums for the presentation of diverse opinions and positions by scientists worldwide, regardless of their race, citizenship, gender, religion, or political viewpoint. Opinions presented in this publication do not reflect official positions of the Society. Notes Copyright © 1968, The Geological Society of America, Inc. Copyright is not claimed on any material prepared by U.S.
    [Show full text]
  • Relations Between Hinterland and Foreland Shortening Sevier Orogeny
    TECTONICS, VOL. 19, NO. 6, PAGES 1124-1143 DECEMBER 2000 Relations between hinterland and foreland shortening: Sevier orogeny,central North American Cordillera WandaJ. Taylor •, JohnM. BartIcy2,Mark W. Martin3, John W. Geissmann, J.Douglas Walker •, Phillip A. Armstrong6,and Joan E. Fryxell7 Abstract. The tectonic relations between foreland and hinterland betweencentral Nevada and Utah thrusts,or that the Utah thrusts deformationin noncollisionalorogens are criticalto understanding persistinto southeastern Nevada but are located east of thelongitude theoverall development of orogens.The classiccentral Cordilleran of the central Nevada thrust belt. As a result of overall cratonward forelandfold-and-thrust belt in the United States(Late Jurassicto migrationof thrusting,the centralNevada thrust belt probably earlyTertiary Sevier belt) andthe moreinternal zones to the west formed the Cordilleran foreland fold-thrust belt early in the (centralNevada thrust belt) providedata critical to understanding shorteningevent but later lay in thehinterland of theSevier fold- the developmereof internaland externalparts of orogens. The thrustbelt of Idaho-Wyoming-Utah. GardenValley thrustsystem, part of the centralNevada thnkst belt, crops out in south-centralNevada within a region generally considered to be the hinterland of the Jurassic to Eocene Sevier 1. Introduction thrustbelt. The thrustsystem consists of at leastfour principal Manyinvestigations in the North American Cordillera and the thrustplates composed of strataas youngas Pennsylvanianin age
    [Show full text]
  • Geologyofnevada.Pdf
    Geology of Nevada Jonathan G. Price Preprint from Castor, S.B., Papke, K.G., and Meeuwig, R.O., eds., 2004, Betting on Industrial Minerals, Proceedings of the 39th Forum on the Geology of Industrial Minerals, May 19–21, 2003, Sparks, Nevada: Nevada Bureau of Mines and Geology Special Publication 33. Abstract The geology of Nevada is the foundation of its natural Geology plays a central role in Nevada’s human history, resources and is closely linked to its human history. The economy, and future. Cordilleran tectonics have created the Basin complex geologic history of the state relates to such and Range landscape and interior drainage of the Great Basin, provided a rain shadow to make Nevada the nation’s driest state, resources as minerals, water, and energy; to environmental and generated frequent earthquakes along normal and strike-slip issues; and to natural hazards. This article draws heavily faults. Geology is key to reducing risks from Nevada’s natural and from the references listed in the bibliography for general anthropogenic hazards (earthquakes, flash floods, drought, land information on the geology of the state, particularly subsidence, erosion after wildland fires, landslides, swelling and Stewart (1980), Stewart and Carlson (1978), Price and collapsing soils, radon, arsenic, and others). others (1999), and Price (2002). Nevada’s geologic fortunes make it the leading state in the production of gold, silver, barite, lithium, and mercury and a major Mountain ranges in Nevada, commonly about 10 producer of geothermal power and gypsum. The metals are primarily miles wide and rarely longer than 80 miles, are separated related to igneous activity, with major pulses of magma during the by valleys.
    [Show full text]
  • How Laramide-Age Hydration of North American Lithosphere by The
    InternationalGeologyReview,Vol.45,2003,p.575–595. Copyright©2003byV.H.Winston&Son,Inc.Allrightsreserved. HowLaramide-AgeHydrationofNorthAmericanLithosphere bytheFarallonSlabControlledSubsequentActivity intheWesternUnitedStates EUGENEHUMPHREYS,1 DepartmentofGeologicalSciences,UniversityofOregon,Eugene,Oregon97403 ERINHESSLER,2 DepartmentofGeologicalSciences,UniversityofOregon,Eugene,Oregon97403 KENNETHDUEKER, DepartmentofGeologyandGeophysics,UniversityofWyoming,Laramie,Wyoming82071 G.LANGFARMER, DepartmentofGeologicalSciences,UniversityofColorado,Boulder,Colorado80309 ERICERSLEV, DepartmentofEarthResources,ColoradoStateUniversity,FortCollins,Colorado80523 ANDTANYAATWATER DepartmentofGeologicalSciences,UniversityofCalifornia,SantaBarbara,California93106 Abstract StartingwiththeLaramideorogenyandcontinuingthroughtheCenozoic,theU.S.Cordilleran orogenisunusualforitswidth,natureofuplift,andstyleoftectonicandmagmaticactivity.We presentteleseismictomographyevidenceforathicknessofmodifiedNorthAmericalithosphere 200kmbeneathColoradoand>100kmbeneathNewMexico.Existingexplanationsforupliftor magmatismcannotaccommodatelithospherethisthick.Imagedmantlestructureislowinseismic velocityroughlybeneaththeRockyMountainsofColoradoandNewMexico,andhighinvelocityto theeastandwest,beneaththetectonicallyintactGreatPlainsandColoradoPlateau.Structureinter- naltothelow-velocityvolumehasaNEgrainsuggestiveofinfluencebyinheritedPrecambrian sutures.Weconcludethatthehigh-velocityuppermantleisPrecambrianlithosphere,andthelow- velocityvolumeispartiallymoltenPrecambrianNorthAmericamantle.
    [Show full text]
  • Sevier-Age Thrust Fault Structures Control the Location of Base- and Precious-Metal Mining Districts in the Oquirrh Mountains, Utah by Edwin W
    Sevier-age Thrust Fault Structures Control the Location of Base- and Precious-Metal Mining Districts in the Oquirrh Mountains, Utah by Edwin W. looker1 Open-File Report 98-234 1998 This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards or with the North American Stratigraphic Code. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government U.S. DEPARTMENT OF THE INTERIOR U.S. GEOLOGICAL SURVEY Menlo Park, California CONTENTS Page Abstract............................................... ... 4 Introduction ..................................... ......... 5 Geologic Setting of North-Central Utah .......................... 7 Oquirrh Mountains Nappes .................................. ..11 Structural and Stratigraphic Characteristics of Mining Districts in the Oquirrh Mountains ........................... ..14 Bingham (West Mountain) mining district ................ .14 Mercur (Camp Floyd) Mining District ..................... 20 Ophir Mining District.................................. .27 Stockton (Rush Valley) Mining District ................... 32 Barneys Canyon-Melco Mining Area ..................... 35 Conclusions ................................................ 39 Acknowledgments .......................................... .43 References Cited ............................................ .44 FIGURES Figure Page 1. Location of the Oquirrh Mountains and its mining districts in north-central Utah. ........................
    [Show full text]
  • Pennsylvanian to Cretaceous Folds and Thrusts in South-Central Nevada: Evidence from the Timpahute Range
    UNLV Theses, Dissertations, Professional Papers, and Capstones 12-1-2013 Pennsylvanian to Cretaceous folds and thrusts in south-central Nevada: evidence from the Timpahute Range Angela Giovanna Russo University of Nevada, Las Vegas Follow this and additional works at: https://digitalscholarship.unlv.edu/thesesdissertations Part of the Geology Commons, and the Tectonics and Structure Commons Repository Citation Russo, Angela Giovanna, "Pennsylvanian to Cretaceous folds and thrusts in south-central Nevada: evidence from the Timpahute Range" (2013). UNLV Theses, Dissertations, Professional Papers, and Capstones. 2023. http://dx.doi.org/10.34917/5363938 This Thesis is protected by copyright and/or related rights. It has been brought to you by Digital Scholarship@UNLV with permission from the rights-holder(s). You are free to use this Thesis in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s) directly, unless additional rights are indicated by a Creative Commons license in the record and/ or on the work itself. This Thesis has been accepted for inclusion in UNLV Theses, Dissertations, Professional Papers, and Capstones by an authorized administrator of Digital Scholarship@UNLV. For more information, please contact [email protected]. PENNSYLVANIAN TO CRETACEOUS FOLDS AND THRUSTS IN SOUTH-CENTRAL NEVADA: EVIDENCE FROM THE TIMPAHUTE RANGE by Angela Giovanna Russo Bachelor of Science Northern Kentucky University 2007
    [Show full text]
  • Geologic Time Scale with Major Events in Nevada History
    Table 1. Geologic time scale with major events in Nevada history. Million years before present ****************************************************************************************************************** CENOZOIC Quaternary Modern earthquakes, mountain building, volcanism, and geothermal activity are expressions of Basin and Range extension that began in the Tertiary Period. The crust is being pulled apart in Nevada, causing valleys to drop relative to mountains. Prior to 10,000 years ago, ice ages caused glaciers to form in the higher mountains and large lakes to develop, in places connecting today's valleys. 1.6 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Tertiary Basin and Range extension began about 30 to 40 million years ago. Igneous activity during the Tertiary Period was caused not only by extension but also by subduction (descent of oceanic crust into the Earth's mantle) of oceanic plates beneath the North American Plate and, in northern Nevada, by motion of the crust over the Yellowstone hot spot in the mantle. Numerous Nevada ore deposits, including most major gold and silver deposits and the copper ores near Battle Mountain, formed during this time. Gypsum deposits formed from evaporating lakes in southern Nevada. 65 **************************************************************************************************************** MESOZOIC Cretaceous The Cretaceous Period and
    [Show full text]
  • Extent and Mechanism of Footwall Shear Adjacent to the Ruby's Inn Thrust Fault, Southern Utah
    The Compass: Earth Science Journal of Sigma Gamma Epsilon Volume 84 Issue 1 Article 5 1-6-2012 Extent and Mechanism of Footwall Shear Adjacent to the Ruby's Inn Thrust Fault, Southern Utah Skyler B. May Southern Utah University, [email protected] Roger E. Leavitt Southern Utah University, [email protected] John S. MacLean Southern Utah University, [email protected] Follow this and additional works at: https://digitalcommons.csbsju.edu/compass Part of the Earth Sciences Commons Recommended Citation May, Skyler B.; Leavitt, Roger E.; and MacLean, John S. (2012) "Extent and Mechanism of Footwall Shear Adjacent to the Ruby's Inn Thrust Fault, Southern Utah," The Compass: Earth Science Journal of Sigma Gamma Epsilon: Vol. 84: Iss. 1, Article 5. Available at: https://digitalcommons.csbsju.edu/compass/vol84/iss1/5 This Article is brought to you for free and open access by DigitalCommons@CSB/SJU. It has been accepted for inclusion in The Compass: Earth Science Journal of Sigma Gamma Epsilon by an authorized editor of DigitalCommons@CSB/SJU. For more information, please contact [email protected]. EXTENT AND MECHANISM OF FOOTWALL SHEAR ADJACENT TO THE RUBY'S INN THRUST FAULT, SOUTHERN UTAH Skyler B. May, Roger E. Leavitt, and John S. MacLean Department of Physical Science Southern Utah University 351 W. University Blvd. Cedar City, UT 84720 [email protected] ABSTRACT The Ruby’s Inn Thrust, located in the Bryce Canyon region, is an uncharacteristic demonstration of a south-directed shortening episode located near the predominately east- directed contractional structures of the Sevier Orogeny. The Paleocene to Eocene Claron Formation in the footwall of the Ruby’s Inn Thrust contains conjugate shear structures and vertical fault planes with slickensides and slickenlines, indicating complex multidirectional shearing.
    [Show full text]
  • American Journal of Science, Vol
    [American Journal of Science, Vol. 304, February, 2004,P.105–168] American Journal of Science FEBRUARY 2004 LATE JURASSIC TO EOCENE EVOLUTION OF THE CORDILLERAN THRUST BELT AND FORELAND BASIN SYSTEM, WESTERN U.S.A. P. G. DeCELLES Department of Geosciences, University of Arizona, Tucson, Arizona 85721 U.S.A.; [email protected] ABSTRACT. Geochronological, structural, and sedimentological data provide the basis for a regional synthesis of the evolution of the Cordilleran retroarc thrust belt and foreland basin system in the western U.S.A. In this region, the Cordilleran orogenic belt became tectonically consolidated during Late Jurassic time (ϳ155 Ma) with the closure of marginal oceanic basins and accretion of fringing arcs along the western edge of the North American plate. Over the ensuing 100 Myr, contractile deformation propagated approximately 1000 kilometers eastward, culminating in the formation of the Laramide Rocky Mountain ranges. At the peak of its development, the retroarc side of the Cordillera was divided into five tectonomorphic zones, including from west to east the Luning-Fencemaker thrust belt; the central Nevada (or Eureka) thrust belt; a high-elevation plateau (the “Nevadaplano”); the topographically rugged Sevier fold-thrust belt; and the Laramide zone of intraforeland basement uplifts and basins. Mid-crustal rocks beneath the Nevadaplano experienced high-grade metamorphism and shortening during Late Jurassic and mid- to Late Cretaceous time, and the locus of major, upper crustal thrust faulting migrated sporadically eastward. By Late Cretaceous time, the middle crust beneath the Nevadaplano was experiencing decompression and cooling, perhaps in response to large-magnitude ductile extension and isostatic exhumation, concurrent with ongoing thrusting in the frontal Sevier belt.
    [Show full text]
  • High-Frequency Tectonic Sequences in the Campanian Castlegate Formation During a Transition from the Sevier to Laramide Orogeny, Utah, U.S.A
    University of New Orleans ScholarWorks@UNO University of New Orleans Theses and Dissertations Dissertations and Theses Spring 5-13-2016 High-frequency tectonic sequences in the Campanian Castlegate Formation during a transition from the Sevier to Laramide orogeny, Utah, U.S.A. David B. Cross University of New Orleans, [email protected] Follow this and additional works at: https://scholarworks.uno.edu/td Part of the Geology Commons, Stratigraphy Commons, and the Tectonics and Structure Commons Recommended Citation Cross, David B., "High-frequency tectonic sequences in the Campanian Castlegate Formation during a transition from the Sevier to Laramide orogeny, Utah, U.S.A." (2016). University of New Orleans Theses and Dissertations. 2133. https://scholarworks.uno.edu/td/2133 This Thesis is protected by copyright and/or related rights. It has been brought to you by ScholarWorks@UNO with permission from the rights-holder(s). You are free to use this Thesis in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights- holder(s) directly, unless additional rights are indicated by a Creative Commons license in the record and/or on the work itself. This Thesis has been accepted for inclusion in University of New Orleans Theses and Dissertations by an authorized administrator of ScholarWorks@UNO. For more information, please contact [email protected]. High-frequency tectonic sequences in the Campanian Castlegate Formation during a transition from the Sevier to Laramide orogeny, Utah, U.S.A. A thesis Submitted to the Graduate Faculty of the University of New Orleans in partial fulfillment of the requirements for the degree of Master of Science In Earth and Environmental Sciences by David Cross B.S.
    [Show full text]