DOCSLIB.ORG

Brief Overview of North American Cordilleran Geology by Cin-Ty Lee Topography Map of North America

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Brief Overview of North American Cordilleran Geology by Cin-Ty Lee Topography Map of North America Brief overview of North American Cordilleran geology by Cin‐Ty Lee Note: make sure to take notes as I will talk or sketch on the board many things that are not presented explicitly in these slides Topography map of North America Topography map How does the NthNorth AiAmerican Cor dillera fit itinto a glbllobal contt?text? Dickinson 2004 P‐wave tomography: Seismic structure beneath western USA Burdick et al. 2008 Crustal provinces of North America (Laurentia) ‐Proterozoic and Archean terranes were already assembled by 1.6 Ga Hoffman, 1988 Crustal provinces in southwestern USA Hoffman, 1988 Bennett and DePaolo, 1987 Some examples of tectonic margins for your reference Dickinson and Snyder, 1978 1.1 Ga = Rodinia Super‐continent (Grenvillian age) Neo‐Proterozoic = Rodinia breaks up “western” margin of Laurentia represents a passive margin due to opening of the Panthalassan ocean 700‐400 Ma Western margin of Laurentia represents a passive margin Dickinson and Snyder, 1978 400‐250 Ma Passive margin is interrupted in Devonian times by the accretion of island arcs Antler and Sonoma orogenies Accretion of allochthonous terranes to the western margin of the NhNorth AiAmerican craton Antler/Sonoma orogenies result in the accretion of Paleozoic island arc terranes to western North America Permian Formation of Pangea “”“western” margin of NhNorth AiAmerica now didominate d by subduct ion zone 250‐50 Ma Subduction results in continued accretion of fringing island arcs and the generation of continental magmatic arcs Sierra Nevada batholith Sevier and Laramide Orogenies 150‐70 Ma Sevier orogeny and continen ta l arc magmatism Thin‐skinned deformation ‐ thrust sheets One view of convergent margin of western North America between 180‐50 My DeCelles, 2004 Late Cretaceous Present‐day gggeologic map of western North America, showing salient Cretaceous and younger tectonic features DeCelles, 2004 Cretaceous (Turonian) Generation of deep basins behind the arc aka Cretaceous Inland Sea ‐high organic content (black shales, coal) ‐btitbentonite (l(clays fdformed from ash) DeCelles, 2004 Cretaceous (Maastrichtian) Isopach map back arc basins DeCelles, 2004 Back arc basins may be related to dynamic topography and flexure DeCelles, 2004 Taken after Gurnis Migration of arc magmatic front eastward ~70 Ma, Sierran arc magmatism cuts off, and then sweeps eastward Eastward migration of arc front is thought to be related to flat subduction beginning at ~74 Ma and continuing until ~40 Ma Dickinson and Snyder, 1978 Flat subduction results in thick‐skinned compressional deformation ‐ LARAMIDE OROGENY ‐ basement‐core uplifts ‐ examples of Laramide uplifts include the Rocky Mountains, Colorado Plateau, Wind River Range, Tetons End result of Laramide orogeny is a thickened crust Magmatism associated with the Laramide orogeny ‐ Andesitic volcanoes near Yellowstone (the Absaroka Range) are associated with Laramide magmatism At ~30 Ma, compressional forces along the edge of and beneath North America begin to decrease as the Pacific‐Farallon ridge approaches the margin. Flat‐subducting Farallon pltlate “ll”“rolls” bkback or collapses Laramide oroggyeny ends Thickened North American Cordillera begins to collapse gravitationally Collision of Pacific‐Farallon Ridge with North American trench, terminates subduction and generates a transform fault (the San Andreas). A “slabless” window opens up beneath western USA. Basin and Range style extension kicks in Late Cenozoic lithosphere extension results in the generation of decompression magmatism in the underlying asthenosphere Yellowstone hotspot appears (not obviously related to extension; thought to be a plume) DeCelles, 2004 Geologic summary Dickinson, 2004 Useful Websites Lava and magma database for western USA www.navdata.org Global supercontinent cycles www.scotese.com San Andreas Fault plate reconstructions (Tanya Atwater) http://emvc.geol.ucsb.edu/downloads.php.
Load more

Recommended publications
  • Two Contrasting Phanerozoic Orogenic Systems Revealed by Hafnium Isotope Data William J
    ARTICLES PUBLISHED ONLINE: 17 APRIL 2011 | DOI: 10.1038/NGEO1127 Two contrasting Phanerozoic orogenic systems revealed by hafnium isotope data William J. Collins1*(, Elena A. Belousova2, Anthony I. S. Kemp1 and J. Brendan Murphy3 Two fundamentally different orogenic systems have existed on Earth throughout the Phanerozoic. Circum-Pacific accretionary orogens are the external orogenic system formed around the Pacific rim, where oceanic lithosphere semicontinuously subducts beneath continental lithosphere. In contrast, the internal orogenic system is found in Europe and Asia as the collage of collisional mountain belts, formed during the collision between continental crustal fragments. External orogenic systems form at the boundary of large underlying mantle convection cells, whereas internal orogens form within one supercell. Here we present a compilation of hafnium isotope data from zircon minerals collected from orogens worldwide. We find that the range of hafnium isotope signatures for the external orogenic system narrows and trends towards more radiogenic compositions since 550 Myr ago. By contrast, the range of signatures from the internal orogenic system broadens since 550 Myr ago. We suggest that for the external system, the lower crust and lithospheric mantle beneath the overriding continent is removed during subduction and replaced by newly formed crust, which generates the radiogenic hafnium signature when remelted. For the internal orogenic system, the lower crust and lithospheric mantle is instead eventually replaced by more continental lithosphere from a collided continental fragment. Our suggested model provides a simple basis for unravelling the global geodynamic evolution of the ancient Earth. resent-day orogens of contrasting character can be reduced to which probably began by the Early Ordovician12, and the Early two types on Earth, dominantly accretionary or dominantly Paleozoic accretionary orogens in the easternmost Altaids of Pcollisional, because only the latter are associated with Wilson Asia13.
    [Show full text]
  • Climate Change May Induce Connectivity Loss and Mountaintop Extinction in Central American Forests ✉ Lukas Baumbach 1 , Dan L
    ARTICLE https://doi.org/10.1038/s42003-021-02359-9 OPEN Climate change may induce connectivity loss and mountaintop extinction in Central American forests ✉ Lukas Baumbach 1 , Dan L. Warren 2, Rasoul Yousefpour1 & Marc Hanewinkel 1 The tropical forests of Central America serve a pivotal role as biodiversity hotspots and provide ecosystem services securing human livelihood. However, climate change is expected to affect the species composition of forest ecosystems, lead to forest type transitions and trigger irrecoverable losses of habitat and biodiversity. Here, we investigate potential impacts of climate change on the environmental suitability of main plant functional types (PFTs) across Central America. Using a large database of occurrence records and physiological data, 1234567890():,; we classify tree species into trait-based groups and project their suitability under three representative concentration pathways (RCPs 2.6, 4.5 and 8.5) with an ensemble of state-of- the-art correlative modelling methods. Our results forecast transitions from wet towards generalist or dry forest PFTs for large parts of the study region. Moreover, suitable area for wet-adapted PFTs is projected to latitudinally diverge and lose connectivity, while expected upslope shifts of montane species point to high risks of mountaintop extinction. These findings underline the urgent need to safeguard the connectivity of habitats through biological corridors and extend protected areas in the identified transition hotspots. 1 Chair of Forestry Economics and Forest Planning,
    [Show full text]
  • (1987): "Tectonomagmatic Evolution of Cenozoic Extension in the North American Cordillera"
    Downloaded from http://sp.lyellcollection.org/ by Frances J Cooper on January 21, 2013 Geological Society, London, Special Publications Tectonomagmatic evolution of Cenozoic extension in the North American Cordillera Brian P. Wernicke, Philip C. England, Leslie J. Sonder and Robert L. Christiansen Geological Society, London, Special Publications 1987, v.28; p203-221. doi: 10.1144/GSL.SP.1987.028.01.15 Email alerting click here to receive free e-mail alerts when service new articles cite this article Permission click here to seek permission to re-use all or request part of this article Subscribe click here to subscribe to Geological Society, London, Special Publications or the Lyell Collection Notes © The Geological Society of London 2013 Downloaded from http://sp.lyellcollection.org/ by Frances J Cooper on January 21, 2013 Tectonomagmatic evolution of Cenozoic extension in the North American Cordillera B.P. Wernicke, R.L. Christiansen, P.C. England & L.J. Sonder SUMMARY: The spatial and temporal distributions of Cenozoic extension and magmatism in the Cordillera suggest that the onset of major crustal extension at a particular latitude was confined to a relatively narrow belt (< 100 km, pre-extension) and followed the onset of intermediate and silicic magmatism by no more than a few million years. Extension began in early Eocene time in southern British Columbia, northern Washington, Idaho and Montana. Farther S, extension began at about the Eocene- Oligocene boundary in the Great Basin and slightly later in the Mojave-Sonora Desert region. The intervening area, at the latitude of Las Vegas, remained quiescent until mid- Miocene time. Compositional and isotopic characteristics of most pre-Miocene magmas are consistent with their containing major components of melted continental crust.
    [Show full text]
  • Hydrodynamic Mechanism for the Laramide Orogeny
    Hydrodynamic mechanism for the Laramide orogeny Craig H. Jones1, G. Lang Farmer1, Brad Sageman2, and Shijie Zhong3 1Department of Geological Sciences and CIRES (Cooperative Institute for Research in Environmental Science), University of Colo- rado at Boulder, 2200 Colorado Avenue, Boulder, Colorado 80309-0390, USA 2Department of Earth and Planetary Sciences, Northwestern University, 1850 Campus Drive, Evanston, Illinois 60208-2150, USA 3Department of Physics, University of Colorado at Boulder, 2000 Colorado Avenue, Boulder, Colorado 80309-0390, USA ABSTRACT INTRODUCTION subduction and attendant subduction erosion only affected only a narrow (~200 km) swath The widespread presumption that the Far- The Late Cretaceous to early Tertiary of oceanic lithosphere underthrusting present- allon plate subducted along the base of North Laramide orogeny that affected much of south- day southern California (Barth and Schneider- American lithosphere under most of the western North America was not only a major man, 1996; Saleeby, 2003). If so, why was the western United States and ~1000 km inboard mountain building event, but also coincided with shallowly subducting lithosphere so restricted from the trench has dominated tectonic stud- major shifts in the distribution of both igneous spatially, and how could such narrow “fl at-slab” ies of this region, but a number of variations activity and sedimentary depocenters. Despite produce the array of geologic features generally of this concept exist due to differences in the critical role the Laramide orogeny played in attributed to the Laramide orogeny throughout interpretation of some aspects of this orogeny. the geologic evolution of western North Amer- western North America? We contend that fi ve main characteristics are ica, its origin remains enigmatic (e.g., English To address these issues we explore in this central to the Laramide orogeny and must and Johnston, 2004).
    [Show full text]
  • OPPOSITE THRUST-VERGENCIES in the PRECORDILLERA and WESTERN CORDILLERA in NORTHERN CHILE and Structurally LINKED CENOZOIC PALEOENVIRONMENTAL EVOLUTION
    Fourth /SAG. Goettingen (Germany), 04 - 06//0//999 155 OPPOSITE THRUST-VERGENCIES IN THE PRECORDILLERA AND WESTERN CORDILLERA IN NORTHERN CHILE AND STRUCTURALLy LINKED CENOZOIC PALEOENVIRONMENTAL EVOLUTION Reynaldo CHARRIER(I-7), Gérard HERAIL(2-7), John FLYNN(3), Rodrigo RIQUELME(I-7), Marcelo GARCIA(4-7), Darin CROFf(5) and André WYSS(6) (1) Departamento de Geologfa, Universidad de Chile; [email protected]. (2) IRD, 209-213, Rue La Fayette, 75010 Paris,[email protected]. (3) The Field Museum of Natural History, Chicago, USA. [email protected]. (4) SERNAGEOMIN. Av. Sta. Maria 0104, Providencia, Santiago, Chile. [email protected]. (5) The Field Museum of Natural History, Chicago, and University of Chicago, USA. (6) Department of Geological Sciences, University of California Santa Barbara, USA [email protected]. (7) Convenio IRD-Departamento de Geologïa, Universidad de Chi le. KEY WORDS: Altiplano, Chile, syntectonic sedimentation, Cenozoic paleoenvironment. INTRODUCTION Morphologie units in the northern Chilean Andes parailei one another and the offshore trench. These units are, from west to east: Coastal Cordillera, Central Depression, Precordillera, Western Cordillera and Altiplano (Fig. i). The development of the west part of the Western Cordillera (Chapiquifia-Belén Ridge), in the Chilean Altiplano, was controlled by two diverging, trench-parallel systems of thrusts and folds, one located along the Precordil1era and the other along the eastern side of the Western Cordillera. Although total shortening associated with these systems is only 12 to 14 km, their activity determined the development of fluvial and lacustrine basins which recorded the synorogenic paleoenvironmental evolution of this region. We describe here facies, geometry and chronology of the deposits associated with both systems and provide an explanation for the differing depositional environments developed on the Precordillera and the Western Cordillera.
    [Show full text]
  • Origin of the Colorado Mineral Belt
    Origin and Evolution of the Sierra Nevada and Walker Lane themed issue Origin of the Colorado Mineral Belt Charles E. Chapin New Mexico Bureau of Geology and Mineral Resources, New Mexico Institute of Mining and Technology, Socorro, New Mexico 87801, USA ABSTRACT Laramide plutons (ca. 75–43 Ma) are mainly may have aided the rise of magma bodies into alkaline monzonites and quartz monzonites in the upper crust from batholiths at depth, but had The Colorado Mineral Belt (CMB) is a the northeastern CMB, but dominantly calc- no role in the generation of those batholiths. northeast-trending, ~500-km-long, 25–50-km- alkaline granodiorites in the central CMB. There is the crux of the enigma. wide belt of plutons and mining districts (Colo- Geochemical and isotopic studies indicate From several decades of fi eld work in the rado, United States) that developed within that CMB magmas were generated mainly states of Colorado, New Mexico, and Wyoming, an ~1200-km-wide Late Cretaceous–Paleo- in metasomatized Proterozoic intermediate I became aware of signifi cant differences in geo- gene magma gap overlying subhorizontally to felsic lower crustal granulites and mafi c logic features on opposite sides of the CMB. My subducted segments of the Farallon plate. rocks (± mantle). Late Eocene–Oligo cene roll- goal in this paper is to summarize these differ- Of the known volcanic gaps overlying fl at back magmatism superimposed on the CMB ences, integrate them with the regional tectonic slabs in subduction zones around the Pacifi c during waning of Laramide compression and geochronologic framework, and thereby Basin, none contains zones of magmatism (ca.
    [Show full text]
  • Plate Tectonic Setting of the Andean Cordillera
    183 by Victor A. Ramos Plate tectonic setting of the Andean Cordillera Laboratorio de Tectónica Andina, Universidad de Buenos Aires, Argentina. E-mail: [email protected] The Andes are a natural laboratory for the study of the acterize the different segments are widely variable. The present interaction between subduction of the oceanic plate and overview will focus on the major geological differences among these segments, based on today’s plate-tectonic knowledge of this moun- active geological processes. Inter- and intraplate seis- tain chain. micity, volcanic activity, thick- and thin-skinned fold and thrust belts, and foreland basin subsidence, in con- junction with space geodetic observations, contribute to Major geological provinces characterize the present plate tectonic setting of discrete The Andes north of the Golfo de Guayaquil are unique, as estab- segments of the Andes. The inherited geological history, lished by Gansser (1973). The Northern Andes record an important as well as the present tectonic setting, is responsible for accretion of oceanic crust during Jurassic, late Cretaceous, and Pale- the unique geology of the Northern, Central, and South- ogene times. As a result, the Western Cordillera of Colombia and Ecuador is mainly constituted of an oceanic basement that during ern Andes. The Northern Andes are the result of Meso- accretion was related to ophiolite obduction, important penetrative zoic and Cenozoic collisions of oceanic terranes, prior deformation and metamorphism, in cases up to blue schist facies. to the present Andean-type setting. The Central Andes Further north, the emplacement of the Caribbean nappes was related to the collision of an island arc system, the Bonaire block, during have a long history of subduction and volcanic arc Paleogene times (Bosch and Rodríguez, 1992, Kellogg and Bonini, activity, while the Southern Andes record the closing of 1982).
    [Show full text]
  • The Cordillera of the Andes Boundary Case (Argentina, Chile)
    REPORTS OF INTERNATIONAL ARBITRAL AWARDS RECUEIL DES SENTENCES ARBITRALES The Cordillera of the Andes Boundary Case (Argentina, Chile) 20 November 1902 VOLUME IX pp. 37-49 NATIONS UNIES - UNITED NATIONS Copyright (c) 2006 37 AWARD BY HIS MAJESTY KING EDWARD VII IN THE ARGENTINE- CHI LE BOUNDARY CASE, 20 NOVEMBER 1902 x WHEREAS, by an Agreement dated the 17th day of April 1896, the Argentine Republic and the Republic of Chile, by Their respective Representatives, determined: THAT should differences arise between their experts as to the boundary-line to be traced between the two States in conformity with the Treaty of 1881 and the Protocol of 1893, and in case such differences could not be amicably settled by accord between the two Governments, they should be submitted to the decision of the Government of Her Britannic Majesty; AND WHEREAS such differences did arise and were submitted to the Govern- ment of Her late Majesty Queen Victoria; AND WHEREAS the Tribunal appointed to examine and consider the differences which had so arisen, has — after the ground has been examined by a Com- mission designated for that purpose — now reported to Us, and submitted to Us, after mature deliberation, their opinions and recommendations for Our consideration ; Now, WE, EDWARD, by the grace of God, King of the United Kingdom of Great Britain and Ireland and of the British Dominions beyond the Seas King, Defender of the Faith, Emperor of India, etc., etc., have arrived at the following decisions upon the questions in dispute, which have been referred to Our arbitration, viz. : 1.
    [Show full text]
  • Present Knowledge of the Magmatic Evolution of the Eastern Cordillera of Peru
    Earth-Science Reviews, 18 (1982) 253-283 253 Elsevier Scientific Publishing Company, Amsterdam-Printed in The Netherlands Present Knowledge of the Magmatic Evolution of the Eastern Cordillera of Peru G. Carlier', G. Grandin', G. Laubacher', R. and F. M6gard2 ' ORSTOM, Mission Peru, Apartado 270, Lima 18 (Peru) and 2'4 rue Bayard75008 Paris (France) ' Institut Francais #Etudes Andines, Apartado 278, Lima I8 (Peru) Pontificia Universidad Catdica del Perú, Avda S. Boliuar, Lima 27 (Peru) ABSTRACT Carlier, G., Grandin, G., Laubacher, G., Marócco, R. and Mégard, F., 1982. Present knowledge of the magmatic evolution of the Eastern Cordillera of Peru. Earth-Sci. Rev., 18: 253-283. The studies which have been carried out in the Eastern Cordillera of Peru over the past 20 years prove the existence of at least three orogenic cycles: the Late Precambrian, the Hercynian and the Andean, each one accompanied by a more or less abundant magmatism. (1) The Precambrian. Leaving aside the prasinites, possibly derived from synsedimentary , volcanites, Precambrian magmatism (in the Huanuco region) consists of: a meta-igneous ultramafic to mafic association (serpentinites, meta-gabbros, meta-diorites); syntectonic meta-tonalites; and post-tectonic dioritic and granitic intrusive bodies. (2) The Hercynian (550 to 220 my.). From the Cambrian to the Upper Devonian the existence of a synsedimentary magmatism is known. Syntectonic granites were emplaced during the Eohercynian phase, but the major part of magmatism is of a Late Permian to Early Trias age, and is characterized by the intrusion of granitoids and by volcanism of calc-al- kaline tendency. It appears that the nepheline syenite of Macusani may belong to a terminal episode of this magmatic period.
    [Show full text]
  • The American Cordillera: a Long Journey Through Time & Space
    The American Cordillera: A Long Journey Through Time & Space Part III:The North American Taphrogen Lecture 25: April 25, G. Zandt An overview of the collapse of the American Cordillera 1 Some of the Big Questions • What caused the extreme inboard migration of deformation and magmatism during the Laramide? [Flat Slab] • What caused the mid-Tertiary extensional collapse and ignimbrite flareup? [Slab Rollback] • Why is the extension and associated magmatisn separated into two domains with different spatial-temporal evolutions? • How did the Colorado Plateau escape significant deformation and magmatism during both periods? Major questions we want to address today. 2 North American Cordillera Topography is the first-order expression of orogeny, and high topography extends half way across the continent (>1000 km). And it remains high despite significant extension which normally leads to subsidence. 3 Western US today We will follow Dickinson (2002) in this review of the Cordilleran taphrogen. He follows Sengor in dividing the Basin and Range taphrogen into the Numic and Piman subtaphrogens. Black bodies are core complexes with arrows indicating direction of vergence (movement of upper plate). We will focus today on the relationship between the subtaphrogens and the Colorado Plateau–Laramide Rocky Mountains. Dickinson, W. R., The Basin and Range Province as a Composite Extensional Domain, Int. Geol. Rev., 44, 1-38, 2002. 4 The tectonic evolution of the Cordillera can be divided into 7 frames (Coney): 1) Formation of the continental margin in late Precambrian time and development of the Cordilleran passive margin. 2) Mid- to late Paleozoic brief orogenic events (Antler, Ancestral Rockies, Sonoma orogenies).
    [Show full text]
  • Climate Change in Central America and Mexico: Regional Climate Model Validation and Climate Change Projections
    Clim Dyn DOI 10.1007/s00382-011-1099-9 Climate change in Central America and Mexico: regional climate model validation and climate change projections Ambarish V. Karmalkar • Raymond S. Bradley • Henry F. Diaz Received: 6 January 2010 / Accepted: 10 May 2011 Ó Springer-Verlag 2011 Abstract Central America has high biodiversity, it har- the form of orographic precipitation show significant bors high-value ecosystems and it’s important to provide decreases in precipitation in the dry season. Projected cli- regional climate change information to assist in adaptation matic changes can have detrimental impacts on biodiver- and mitigation work in the region. Here we study climate sity as they are spatially similar, but far greater in change projections for Central America and Mexico using magnitude, than those observed during the El Nin˜o events a regional climate model. The model evaluation shows its in recent decades that adversely affected species in the success in simulating spatial and temporal variability of region. temperature and precipitation and also in capturing regio- nal climate features such as the bimodal annual cycle of keywords Regional climate change Á Biodiversity Á precipitation and the Caribbean low-level jet. A variety of Central America climate regimes within the model domain are also better identified in the regional model simulation due to improved resolution of topographic features. Although, the model 1 Introduction suffers from large precipitation biases, it shows improve- ments over the coarse-resolution driving model in simu- The Mexican and Central American landmass has consid- lating precipitation amounts. The model shows a dry bias erable topographic relief, which implies the existence of in the wet season and a wet bias in the dry season sug- large gradients in many critical climate variables such as gesting that it’s unable to capture the full range of pre- temperature, precipitation, humidity, and wind.
    [Show full text]
  • Eastern Cordillera Real Oriental Paramos and Montane Forests
    ECORREGIONAL ASSESSMENT: EASTERN CORDILLERA REAL ORIENTAL PARAMOS AND MONTANE FORESTS The Nature Conservancy, EcoCiencia y Fundación AGUA. 2005. Evaluación Ecorregional de los Páramos y Bosques Montanos de la Cordillera Real Oriental. Quito-Ecuador. The ecoregional assessment of Eastern Cordillera Real Paramos and Montane Forests was implemented to design a network of conservation areas that can maintain successfully in the long-term characteristic biodiversity of the region, as well as ecological processes. The Tropical Andes region located in northern South America is gifted with an impressive array of biodiversity. The Nature Conservancy (TNC) has worked for several years in collaboration with local organizations implementing conservation actions on this region. Within the Tropical Andes the Eastern Cordillera Real Paramos and Montane Forests are found, which have been identified as strategic areas for directing conservation efforts.The Nothern Andes Program of the World Fund for Nature (WWF), in the biodiversity vision for the Northern Andes, identified 65 priority areas for conservation on this region that groups several ecoregions. This process identified the Eastern Cordillera Real Montane Forests ecoregion as a priority within the ecoregional complex. With this background, the former Ecuador Program (now Northern Tropical Andes Conservation Program) in collaboration with EcoCiencia and Fundación AGUA, decided to develop an ecoregionall assessement on this ecoregion to refine the results and data produced by WWF. The objective
    [Show full text]