DOCSLIB.ORG

F the Round Mountain Plug, Castle Valley, Grand County, Utah

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
F the Round Mountain Plug, Castle Valley, Grand County, Utah (JOO) T~1r t/)(() .S.I.IJ ~ :.-----" RES9~Ref! ·· ItA TION SECTION A Magnetic Investigation·()f the Round Mountain Plug, Castle Valley, Grand County, Utah By R. A. Black . EP 2 3 98 * JU~ 30 19'5 Denver ~y ~.,..s<''~~ ~ Trace Elements In-..esti gations Report 342 UNITED STATES DEPAR.Tl\fENT OF THE INTERIOR GEOLOGICAL SURVEY OFFICIAL USE ONLY Geology and Mineralogy This document consists of 25 pageso Series A UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY A MAGNETIC INVESTIGATION OF THE ROUND MOUNTAIN PLUG CASTLE VALLEY~ GRAND COUNTY~ UTA~ By R., A., Bl ack December 1953 Trace Elements Investigations Report 342 This preliminary report is distributed without editorial and technical review for conformity with official standards and nomenclature& It is not for public inspection or quotationo :A: This report concerns work done on behalf of the Division of Raw Materials of the Uo Sa Atomic Energy Commissiono OFFICIAL USE ONLY OFFICIAL USE ONLY 2 USGS~TEI=342 . GEOLOGY AND MINERALOGY Distribution (Series A) of copies Argonne National Laboratory o o o o 1 Atomic Energy Commission, Washington o o o o o o o o o 1 Battelle Memorial Institute, Columbus o o ~ ~ o o 1 Carbide and Carbon Chemicals Company, Y=l2 Area o 1 Division of Raw Materials, Albuquerque 1 Division of Raw Materials, Butte o f) C) o o 1 Division of Raw Materials, Denver o 1 Division of Raw Materials, Douglas o 9 e 0 0 0 1 Division of Raw Materials, Hot Springs o o o o 1 Division of Raw Materials, Ishpeming o o o o o o o o o 1 Division of Raw Materials, New York o o o o o o 6 Division of Raw Materials, Phoenix o o o o o o o o o 1 Division of Raw Materials, Richfield o o o o 1 Division of Raw Materials, Salt Lake City o o o o o 1 Division of Raw Materials, Washington o o o o o 3 Dow Chemical Company, Pittsburg o o 1 Exploration Division, Grand Junction Operations Office 6 Grand Junction Operations O~fice 1 National Lead Company, Winchester o 1 Technical Information Service, Oak Ri dge 6 Tennessee Valley Authority, Wilson Dam o o o o o o o 1 Uo So Geological Survey~ Alaskan Geology Branch, Menlo Parke o o o o o o 1 Fuels Branch, Washington 1 Geochemistry and Petrology Branch, Washington o 1 Geophysics Branch, Washington o o o 8 MineraJ. Deposits Branch, Washington o 1 Eo Ho Bailey, Menlo Parka o o o o o o o o 0 0 0 1 Ro Ao Black, Grand Junction o o o o o .. o o o 1 Ko Lo Buck, Denvero 1 J., Ro Cooper, Denver a o o 1 No Mo Denson, Denvero o 1 Co Eo Dutton, Madison o ' o o o 1 Ao Lo Brokaw, Grand Junction 2 Lo So Gardner, Albuquerqueo o 0 0 0 0 1 \ Co Bo Hunt, Washingtono 0 0 9 0 1 Mo Ro Klepper, Washington 1 Ao Ho Koschmann, Denver o 1 Ro Ao Laurence, Knoxville 1 Do Mo Lemmon, Washingtono o o o o o 0 0 0 0 0 0 9 1 J o Do Love, Laramie o o o o o o o o o o o 1 Vo Eo McKelvey, Menlo Park o o o o 1 Wo Lo Emerick, Pl ant City o o o o o o o o o 1 Ro Jo Roberts, Salt Lake City o o o o o o a 1 Qo Do Singewald, Beltsville o o o o o 1 Jo Fo Smith, Jro, Denvero o o o o o o 1 Ao Eo Weissenborn, Spoka.ieo 1 TEPC 0, Denver o o 0 0 0 2 TEPCO, RPS, Washingtono 0 0 0 0 0 3 (Including master) 76 OFFICIAL USE ONLY OFFICIAL USE ONLY 3 CONTENTS Page Abstract o o o o o o e o • o o • • o • • o o • " o o • o • o o • o o < 4 Introduction o " " ., " o • co o o • o o o o • o o o o • o 5 Location and topography o • o • • o • ., o o o • • o • • o • • • o o 6 Geolog:y- o o e o e o o o 9 o e e o a o e o o o e o o e o o e e e 6 Magnetic investigations o o o o o e o o o o o o e ., o e o o e ., o o 11 Field procedures o o o o o o o e o o o o o o e o o o o o o o o 11 Theoretical anomalies o o o o " o o o o o o • o o o o o o o o 13 Results o • o o e o • o o o e o o o o o o o e o o o o .. o 17 Conclusion o o o o e o o o o o o o o o o o o o o o o e o o o o e o 24 Literature cited o 0 0 0 0 0 0 0 0 0 0 0 o o o o o o o o o o o o o e 25 ILLUSTRATIONS Figure le Index map of part of the Colorado Plateau showing the location of the Castle Valley area~ Grand Countyp Utah o o o o o o o o o o o o o o o o o c o o o o o 0 " 7 Map of the Castle Valley area, Grand County~ Utah o o 0 0 8 Map showing the location of the magnetic traverses with respect to Round Mountain~ Grand County~ Utah 0 0 0 e 0 0 G 0 e " 0 " 0 " 0 G 0 0 9 e " o o e o 9 Theoretical vertical intensity magnetic anomalies over a vertical dike buried at depths of (A) 200 feet 9 (B) 400 feet~ and (C) 1»000 feet c 0 0 " 15 Theoretical vertical intensity magnetic anomalies over a horizontal cylinder buried at depths of · (A) 200 feet 9 (B) 400 feet~ and (C) 1~000 feet 0 0 0 0 16 6o Diagram showing some of the magnetic profiles in the Castle Valley area9 Grand County~ Utah o o o o o o 18 Diagram showing magnetic profile obtained over Round Mountain9 Castle Valley area~ Grand County, Utah o o • o o o o o o o o o o o o o o o o o 19 Magnetic vertical intensity contour map of the area around Round Mountain~ Castle Valley are~, Grand County9 Utah o o o o o o ~ o o o o ~ o o o 0 0 20 OFFICIAL USE ONLY OFFICIAL USE ONLY 4 A MAGNETIC INVESTIGATION OF THE ROUND MOUNTAIN PLUG7 , CASTLE VALLEYJl GRAND COUNTY, UTAH By Ro Ao Black ABSTRACT A magnetic survey was made in Castle Valley~ Grand County~ Utah~ to determine if the Round Mountain plug was fed laterally from the La Sal Mountains or vertically from a source at deptho Additional measurements were made around the exposure of igneous rock to obtain the shape of the plug at deptho No indication of a buried lateral igneous feeder was detected on the magnetic profileso The magnetic contour map showed that the plug was much larger than indicated by the diorite porphyry outcrop, and that the buried part of the plug southeast of Round Mountain has a higher magnetic susceptibility than the diorite outcropo Theoretical anomalies~ calculated using the susceptibility of the diorite outcrop, indicate that a lateral feeder at a depth of greater than 200 feet could not be de= teetedo The size and shape of the magnetic anomaly as shown on the con= tour map suggest that the plug was fed from a source at deptho OFFICIAL USE ONLY OFFICIAL USE ONLY 5 INTRODUCTION Discussions during the winter of 1952 with Co Bo Hunt of the U.. So Geological Survey concerni~g the intrusives and volcanism phase of Cenozoic studies led to a proposal that a geophysical study be made of the Round Mountain plug in Castle Valley~ Grand County~ Utah, to de= termine if the Round Mountain plug was connec.ted to the La Sal Mountains by a relatively shallow lateral feeder~ or if it was fed from an indi­ vidual source at depth~ and to obtain information on the shape of the intrusiono This survey was part of Colorado Plateau geologic studies being carried out by the Uo So Geological Survey on behalf of the Atomic Energy Commissiono During a series of aeromagnetic traverses by the Uo S .. Geological Survey plane in the La Sal Mountain area in February and March 1952~ an anomaly of 150 gammas had been detected at ~ altitude of 2~000 feet above a point half way up the slope of Round Mountain~ indicating that the diorite porphyry of the plug is fairly magnetico From this information and from the knowledge of the geology of the ~rea~ ·it was decided that a ground magnetic survey could best be used to obtain the desired informa= tion about the Round Mountain plug o A vertical intensity magnetic sur= vey was carried out in Castle Valley9 Utah~ during the period May 5 to June 18~ 1953~ by a field party under the direction of R.. A.. Blacko At various times during this period~ Po E .. Byerly and Ro Eo Warrick of the Geological Survey assisted in obtaining the m~gnetic measurementso OFFICIAL USE ONLY OFFICIAL USE ONLY 6 LOOATION AND TOPOGRAPHY The Castle Valley area is in Grand County~ Utah~ {figo 1) approxi= mately 18 miles northeast of Moab 9 and can be reached by Utah Highway 128., Figure 2 is a more detailed map after Baker (~933) which shows the Valley outline and the location of the Round Mountain stock.
Load more

Recommended publications
  • Outreachnotice
    OUTREACH NOTICE USDA FOREST SERVICE INTERMOUNTAIN REGION, R4 Manti-La Sal National Forest Phone (435) 636-3354 Natural Resource Specialist GS-0401-5/7/9 Response requested by December 7, 2016 Position Description The purpose of this outreach notice is to (1) gauge interest in the position, (2) to alert interested individuals of this upcoming employment opportunity. The position is expected to be advertised on www.usajobs.gov/ in the fall of 2016. (Interested persons should respond using the Outreach Response on page 6). The Moab/Monticello Ranger District of the Manti-La Sal National Forest will be seeking to fill two GS-0410-5/7/9 Natural Resource Specialist positions. The duty stations for the position will be Moab, Utah. Duties include but are not limited to the following: Duties: The duties of these position are varied and diverse. One appointee will perform work associated with the Lands and Recreation Special Uses Program, Minerals and Roads Programs and the other appointee will work primarily in the Recreation Program dealing with developed recreation, interpretation and Recreation Special Uses. Compiles material and supply estimates for recreation facilities, maintenance, and operation. Participates in the drafting of annual work action plans for carrying out recreation management 1 decisions. Participates in the implementation of recreation plan objectives and the full range of recreation uses, administration of special authorization for recreation events and concessionaire operations. Inspects campgrounds and other recreation areas to determine that improvements are properly maintained; gathers data for studies of campground use; conducts compliance checks; assists in preparation of recreation reports; and identifies potential recreation sites.
    [Show full text]
  • OUTREACH NOTICE Forestry Technician, Initial Attack Dispatcher GS-5/6/7 18/8
    OUTREACH NOTICE Forestry Technician, Initial Attack Dispatcher GS-5/6/7 18/8 REGION 4 – MANTI-LA SAL NATIONAL FOREST DUTY STATION: Moab, UTAH POSITION: The Supervisors Office of the Manti-La Sal National Forest will soon be seeking applicants for a Forestry Technician, (Initial Attack Dispatcher), GS-0462-5/6/7 position at the Moab Interagency Fire Center (MIFC). This is a permanent part-time position (18/8) with the duty station in Moab, Utah. DUTIES: This position is located at MIFC where the incumbent will be an Initial Attack Dispatcher for the interagency center and assist with other fire center duties as assigned. The Moab Interagency Fire Center represents the five wildland fire agencies in Southeastern Utah, providing resource coordination between the Manti-La Sal National Forest, Division of Forestry, Fire and State Lands, Bureau of Land Management, National Park Service and Bureau of Indian Affairs. The MIFC dispatch area involves nearly 10 million acres of terrain that ranges from grasslands at 4,000 feet to forested lands above 10,000 feet in elevation. Land status throughout the area is highly fragmented. Resources include two 10-person crews, 11 engines and 1 Type 3 Helicopter with crew and the Red Rock Regulars (Type 2 IA Handcrew). MIFC resources respond to an average of 200 to 400 incidents per year, with a fire season that extends from March through Mid November. This position is located in an initial attack fire suppression organization where the employee performs a variety of staff and administrative duties relating to fire suppression activities and the support of fire management programs.
    [Show full text]
  • Acrobat Distiller, Job 6
    Magmatism in Western Cascades Arc Early Tertiary Magmatism • Active from 38 to 17 Ma • New volcanic activity west of Clarno Fm Part II and south into Oregon Reference: • Western Cascade volcanism was mostly andesitic DNAG v. 3, Ch. 7, pp 294-314 • Some rhyolitic ash-flow sheets • Broad curving continuous belt of volcanoes Cascade-John Day Washington Magmatism • Overlapped older Challis and Tuscarora belts – Numerous shallow batholiths – Snowqualamie Batholith – Tatoosh Pluton • Represent subvolcanic magmatism • Younger High Cascades follows the same trend Western Oregon Southern Oregon • Oligocene calc-alkaline volcanic rocks • No units younger than 17 Ma present – Unconformable on Eocene rocks • Mafic alkalic rocks developed in • Andesite-dacite-rhyolite erupted from front of the western Cascades numerous centers • Nepheline syenite, Camptonite, • Few shallow subvolcanic intrusives Ferrogabbro 1 Cascade-John Day Northern California • Basaltic to rhyolitic volcanism • Age range of 31 to 20 Ma • Andesite mudflow breccias in Sierra foothills – Cedarville Volcanics – Extend into Nevada – Andesite breccias and rhyolite tuffs Cascade-John Day John Day Magmatic Region • Age of 36 to 18 Ma • Much downwind fall out from Western Cascades volcanism • High-silica, alkali rhyolite is common • Local alkali basalt to trachyte eruptions Southern Oregon Other Locations • Rhyolite to bimodal rhyolite- • Lovejoy basalt in California trachyandesite – Alkali basalts and trachyandesites • Summer lake, Goose Lake, Albert Rim • Owyhee Mountains, Idaho – Rhyolites
    [Show full text]
  • Slickrock Foot Trail Provides an Opportunity for Beginners to Orient Themselves Dominating the Rest of the Scene Is the to Trails in Canyonlands National Park
    Viewpoint 3 Viewpoint 4 Lower Little Spring Canyon Big Spring Canyon Slickrock Gifts from the Sea A Monumental Change The gray and purple rock layers visible in Grand View Point and Junction Butte, rising Foot Little Spring Canyon contrast sharply with a thousand feet above Big Spring Canyon, are the red and white rock that dominates most visible to the north. These landmarks show of The Needles district. Both, however, were erosional patterns typical of sedimentary derived from the same source — the ocean. rock. The various layers exhibit different Trail Millions of years ago this area was covered by degrees of resistance to weathering. Softer a shallow sea. Little Spring Canyon is pre- rocks, such as shales and mudstones, crumble TRAIL GUIDE dominately limestone, a hard sedimentary into slopes. Sandstones, limestones and other rock composed mostly of calcium harder rocks maintain vertical bluffs. The carbonate, the hard parts of massive Wingate cliffs, the most prominent tiny marine animals that layer, were once enormous sand dunes. settled to the ocean floor as they died. Fossilized The Canyonlands region re- remains of crinoids, mained near sea level during brachiopods and other the time these rock layers Navajo Ss. Brachiopod marine invertebrates were deposited. Change Kayenta Fm. give testimony came when massive forces to the ocean’s within the earth pushed Wingate Ss. Crinoid presence. these layers upward, forming the Monument The spires of The Needles district display Uplift and causing the Chinle Fm. the red-and-white banding of Cedar Mesa rock layers to fracture. Sandstone, which was formed as sandy Cracks and joints Moenkopi Sh.
    [Show full text]
  • Seeing the Park Arches National Park • Utah
    SEEING THE PARK You can get to most of the scenic features of the park from the road, but the trails will yield much that is missed by motorists. Courthouse Towers. A paved entrance road leaves U.S. ARCHES NATIONAL PARK • UTAH 160 at the park visitor center 5 miles north of Moab, climbs the standstone cliffs behind the visitor center, and passes first through the Courthouse Towers section. Here you may want to take the easy 1-mile hike through Park Avenue, a narrow corridor through towering red-rock walls topped by an orderly array of towers and spires, which resembles the skyscrapers of a great city. As there are parking areas at each end of the trail, one member of your party can drive around to pick up the hikers. There are exciting views of the La Sal Mountains, Courthouse Canyon, and The Windows Section from the parking areas and roadside turnouts. The Windows Section. In the east-central part of the park, which is the most readily accessible, a great mass of the Entrada Sandstone towers over the surrounding plain. In these walls the forces of nature have carved eight immense arches and many smaller windows, passageways, FOR YOUR SAFETY coves, pinnacles, spires, and balanced rocks. Here are The climate and landscape at Arches pre­ Double Arch, Parade of the Elephants, Cove of the Caves, sent special problems involving the safety of North and South Windows, Balanced Rock, and other every visitor. Read these precautions care­ erosional features. This section is 12 miles from the visitor fully.
    [Show full text]
  • Manti-La Sal National Forest Visitor Guide
    anti-La Sal National Forest M VISITOR GUIDE Ancient Lands Modern Get-away Dark Canyon Wilderness La Sal Pass Maple Canyon (© Jason Stevens) he deep sandstone canyons, mountaintops, meadows, lakes and streams of the Manti-La Sal National Forest have What’s Inside T beckoned people for ages. Evidence of prehistoric and historic Get to Know Us .................... 2 life is found throughout the four islands of the forest. From Wilderness ........................... 3 the Abajos and La Sals in southeastern Utah to the Wasatch Scenic Byways ..................... 4 Plateau and Sanpitch Mountains hundreds of miles away in Map ...................................... 6 Campgrounds ..................... 10 central Utah, the diverse and scenic landscapes are rich with Cabins ................................. 11 fossils, cliff dwellings, historic waterways, and old mines. Activities ............................. 12 Know Before You Go........... 15 Today the forest offers people Contact Information ........... 16 Fast Forest Facts a retreat from the hurry of modern life. Those who seek solitude and Acres: 1.4 million quiet can find it here. Intrepid adventurers Mining: Source of 85% of coal mined will discover mountains to scale, trails to in Utah; important source of uranium explore, waters to fish, and woods where in the 1940s-1970s they can hunt. Scenic byways and backways Aberts Amazing Feature: Forest habitat summon motorists looking for stunning vistas, squirrel provides for the densest black bear and abundant camping areas are perfect for and
    [Show full text]
  • Arches Visitor Guide 2017
    National Park Service Visitor Guide U.S. Department of the Interior Arches The La Sal Mountains with the Windows Section in the foreground NPS / PAUL STOLEN We Need Your Help BY RACHEL JOHA Arches National Park is a destination for over 1.5 million people a year. Numbers like that can have a huge impact on the landscape. No matter your experience in the outdoors, we all play a role in protecting and preserving our public lands. The Seven Principles of Leave No Trace are helpful guidelines to minimize your impact here at Arches or anywhere you visit. Plan Ahead and Prepare Dispose of Waste Properly Minimize Campfire Impacts Be Considerate of Other Visitors Plan your trip activities to match your “Pack it in, pack it out.” Don’t leave Never leave a fire unattended, and Avoid disrupting natural quiet with loud goals, skills, and abilities. Research the behind any trash or food scraps. In thoroughly extinguish all fires. Fires are music or shouting. Remember— you park and current conditions ahead of arid climates like ours, organic litter only allowed in designated pits at Devils share public lands with other visitors. time. Bring enough water, a map, food, like orange peels or nut shells does not Garden Campground and in picnic Respect and protect the quality of and appropriate gear so you don’t need decompose quickly. “Go before you go.” areas. Collecting firewood or kindling is everyone’s outdoor experience. rescuing. Dozens of hikers at Delicate Before starting a hike, use the bathroom not allowed in the park. Arch and Devils Garden get in trouble and carry a human waste disposal bag Thank You! every year from lack of preparation.
    [Show full text]
  • See & Do Guide
    Photo by Jake Campos Fotoproduktion Campos Jake by Photo [email protected] utahscanyoncountry.com trading post. trading 800-574-4386 | 435-587-3235 discovermoab.com 84535 UT Monticello 490, Box PO 435-259-8825 US163 and County Rd. 421. Allow 2 hours to visit the museum and and museum the visit to hours 2 Allow 421. Rd. County and US163 County Juan San - Country Canyon Utah’s 84532 UT Moab, film, Earth Spirit. Lodging, campground. 2 miles W of the junction of of junction the of W miles 2 campground. Lodging, Spirit. Earth film, tours, Navajo arts & crafts, a restaurant, and evening showings of the the of showings evening and restaurant, a crafts, & arts Navajo tours, Kane Gulch, signed. Allow 3 hrs to multiple days. multiple to hrs 3 Allow signed. Gulch, Kane from the film She Wore A Yellow Ribbon is here. The lodge offers offers lodge The here. is Ribbon Yellow A Wore She film the from Cedar Mesa area. Detailed maps are recommended. Ranger station at at station Ranger recommended. are maps Detailed area. Mesa Cedar on the Navajo people and the films made in the valley. The cabin cabin The valley. the in made films the and people Navajo the on Station is a 5 hour hike. Many day hikes are possible throughout the the throughout possible are hikes day Many hike. hour 5 a is Station offers a museum in the original 1926 residence with special emphasis emphasis special with residence 1926 original the in museum a offers (435-587-1500). Access to Grand Gulch from Kane Gulch Ranger Ranger Gulch Kane from Gulch Grand to Access (435-587-1500).
    [Show full text]
  • The Eastern San Juan Mountains 17 Peter W
    Contents Foreword by Governor Bill Ritter vii Preface ix Acknowledgments xi Part 1: Physical Environment of the San Juan Mountains CHAPTER 1 A Legacy of Mountains Past and Present in the San Juan Region 3 David A. Gonzales and Karl E. Karlstrom CHAPTER 2 Tertiary Volcanism in the Eastern San Juan Mountains 17 Peter W. Lipman and William C. McIntosh CHAPTER 3 Mineralization in the Eastern San Juan Mountains 39 Philip M. Bethke CHAPTER 4 Geomorphic History of the San Juan Mountains 61 Rob Blair and Mary Gillam CHAPTER 5 The Hydrogeology of the San Juan Mountains 79 Jonathan Saul Caine and Anna B. Wilson CHAPTER 6 Long-Term Temperature Trends in the San Juan Mountains 99 Imtiaz Rangwala and James R. Miller v Contents Part 2: Biological Communities of the San Juan Mountains CHAPTER 7 Mountain Lakes and Reservoirs 113 Koren Nydick CHAPTER 8 Fens of the San Juan Mountains 129 Rodney A. Chimner and David Cooper CHAPTER 9 Fungi and Lichens of the San Juan Mountains 137 J. Page Lindsey CHAPTER 10 Fire, Climate, and Forest Health 151 Julie E. Korb and Rosalind Y. Wu CHAPTER 11 Insects of the San Juans and Effects of Fire on Insect Ecology 173 Deborah Kendall CHAPTER 12 Wildlife of the San Juans: A Story of Abundance and Exploitation 185 Scott Wait and Mike Japhet Part 3: Human History of the San Juan Mountains CHAPTER 13 A Brief Human History of the Eastern San Juan Mountains 203 Andrew Gulliford CHAPTER 14 Disaster in La Garita Mountains 213 Patricia Joy Richmond CHAPTER 15 San Juan Railroading 231 Duane Smith Part 4: Points of Interest in the Eastern San Juan Mountains CHAPTER 16 Eastern San Juan Mountains Points of Interest Guide 243 Rob Blair, Hobie Dixon, Kimberlee Miskell-Gerhardt, Mary Gillam, and Scott White Glossary 299 Contributors 311 Index 313 vi Part 1 Physical Environment of the San Juan Mountains CHAPTER ONE A Legacy of Mountains Past and Present in the San Juan Region David A.
    [Show full text]
  • Colorado Plateau Magmatism and Uplift by Warming of Heterogeneous Lithosphere
    Vol 459 | 18 June 2009 | doi:10.1038/nature08052 LETTERS Colorado Plateau magmatism and uplift by warming of heterogeneous lithosphere Mousumi Roy1, Thomas H. Jordan2 & Joel Pederson3 The forces that drove rock uplift of the low-relief, high-elevation, Colorado Plateau and, additionally, that this mechanism explains the tectonically stable Colorado Plateau are the subject of long-standing observed rates of encroachment of the onset of Cenozoic magmatism debate1–5. While the adjacent Basin and Range province and Rio onto the plateau. Grande rift province underwent Cenozoic shortening followed by The widespread distribution of shallow-marine and coastal-affinity extension6, the plateau experienced 2 km of rock uplift7 without sediments of late-Cretaceous age on the Colorado Plateau suggests significant internal deformation2–4. Here we propose that warming relatively uniform elevation of the region at or near sea-level at that of the thicker, more iron-depleted Colorado Plateau lithosphere8–10 time. The present-day elevations of these strata can be reconstructed over 35–40 Myr following mid-Cenozoic removal of the Farallon (including eustasy) to determine spatially varying net rock uplift and plate from beneath North America11,12 is the primary mechanism erosion functions across the plateau7, with a mean of ,1.9 km net driving rock uplift. In our model, conductive re-equilibration not Cenozoic rock uplift (Fig. 1a) and net Cenozoic erosion of ,481 m only explains the rock uplift of the plateau, but also provides a (Fig. 1b). These reflect net deposition in early-Cenozoic time, mid- robust geodynamic interpretation of observed contrasts between Cenozoic stability and then enhanced erosion since drainage integ- the Colorado Plateau margins and the plateau interior.
    [Show full text]
  • Geologic Resource Evaluation Report, Canyonlands National Park
    National Park Service U.S. Department of the Interior Natural Resource Program Center Canyonlands National Park Geologic Resource Evaluation Report Natural Resource Report NPS/NRPC/GRD/NRR—2005/003 Canyonlands National Park Geologic Resource Evaluation Report Natural Resource Report NPS/NRPC/GRD/NRR—2005/003 Geologic Resources Division Natural Resource Program Center P.O. Box 25287 Denver, Colorado 80225 September 2005 U.S. Department of the Interior Washington, D.C. The Natural Resource Publication series addresses natural resource topics that are of interest and applicability to a broad readership in the National Park Service and to others in the management of natural resources, including the scientific community, the public, and the NPS conservation and environmental constituencies. Manuscripts are peer-reviewed to ensure that the information is scientifically credible, technically accurate, appropriately written for the intended audience, and is designed and published in a professional manner. Natural Resource Reports are the designated medium for disseminating high priority, current natural resource management information with managerial application. The series targets a general, diverse audience, and may contain NPS policy considerations or address sensitive issues of management applicability. Examples of the diverse array of reports published in this series include vital signs monitoring plans; "how to" resource management papers; proceedings of resource management workshops or conferences; annual reports of resource programs or divisions of the Natural Resource Program Center; resource action plans; fact sheets; and regularly-published newsletters. Views and conclusions in this report are those of the authors and do not necessarily reflect policies of the National Park Service. Mention of trade names or commercial products does not constitute endorsement or recommendation for use by the National Park Service.
    [Show full text]
  • B2158 Pt 10 Text Copy
    Previous section Volume contents The Petrogenesis of the Colorado Plateau Laccoliths and Their Relationship to Regional Magmatism By Stephen T. Nelson1 and Jon P. Davidson2 CONTENTS Abstract........................................................................................................................... 86 Introduction ....................................................................................................................86 Regional Geologic Setting...................................................................................... 86 Colorado Plateau Structure, Geophysics, and Composition................................... 88 Field Relations........................................................................................................ 88 Geochemical Characteristics of the Laccoliths .............................................................. 89 Magma Chemistry And Petrogenesis in the Henry Mountains...................................... 92 Regional Tectonomagmatic Considerations................................................................... 94 Conclusions .................................................................................................................... 97 Acknowledgments .......................................................................................................... 98 References Cited............................................................................................................. 98 FIGURES 1. Maps showing locations of the Henry, La Sal, and Abajo Mountains,
    [Show full text]