DOCSLIB.ORG

Framework Geologic Map and Structure Sections Along the Bartlett

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Framework Geologic Map and Structure Sections Along the Bartlett Prepared in Cooperation with Pacific Gas and Electric Company Framework Geologic Map and Structure Sections along the Bartlett Springs Fault Zone and Adjacent Area from Round Valley to Wilbur Springs, Northern Coast Ranges, California By Robert J. McLaughlin, Barry C. Moring, Christopher S. Hitchcock, and Zenon C. Valin Pamphlet to accompany Scientific Investigations Map 3395 Version 1.1, September 2018 2018 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior RYAN K. ZINKE, Secretary U.S. Geological Survey James F. Reilly II, Director U.S. Geological Survey, Reston, Virginia: 2018 First release: 2018 Revised: September 2018 (ver. 1.1) For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment—visit http://www.usgs.gov/ or call 1–888–ASK–USGS (1–888–275–8747). For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod/. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this information product, for the most part, is in the public domain, it also may contain copyrighted materials as noted in the text. Permission to reproduce copyrighted items must be secured from the copyright owner. Suggested citation: McLaughlin, R.J., Moring, B.C., Hitchcock, C.S., and Valin, Z.C., 2018, Framework geologic map and structure sections along the Bartlett Springs Fault Zone and adjacent area from Round Valley to Wilbur Springs, northern Coast Ranges, California (ver. 1.1, September 2018): U.S. Geological Survey Scientific Investigations Map 3395, 60 p., https://doi.org/10.3133/sim3395. ISSN 2329-132X (online) Contents Introduction.....................................................................................................................................................1 Present and Previous Studies ............................................................................................................1 Acknowledgments ................................................................................................................................1 Geologic Setting .............................................................................................................................................2 Lithologic and Structural Features of the Metamorphic Basement Terranes .....................................4 Franciscan Complex .............................................................................................................................4 Central Belt ...................................................................................................................................4 Pomo Terrane (Upper Cretaceous to Upper Jurassic) .................................................4 Marin Headlands-Geysers Terrane (Upper Cretaceous–Upper Jurassic) ...............4 Snow Mountain Volcanic Terrane (Lower Cretaceous–Valanginian or younger) ...5 Eastern Belt...................................................................................................................................5 Yolla Bolly Terrane (Upper and Lower Cretaceous to Upper Jurassic, Tithonian) ..6 Pickett Peak Terrane (Lower Cretaceous, Aptian–Barremian)...................................7 Mendocino Pass Terrane (Lower Cretaceous, Valanginian) .......................................7 Coast Range Ophiolite (Upper and Middle Jurassic) .....................................................................8 Great Valley Complex ....................................................................................................................................8 Elder Creek Terrane of the Great Valley Complex (Lower Cretaceous and Upper to Middle Jurassic) ...................................................................................................................................8 Structural Relations .......................................................................................................................................8 Major Faults ...........................................................................................................................................8 Coast Range Fault ........................................................................................................................8 Bartlett Springs Fault Zone ........................................................................................................9 Northern Bartlett Springs Fault Zone ..............................................................................9 Displacement on the Northern Bartlett Springs Fault .........................................9 Lake Pillsbury Releasing Bend ..............................................................................10 Seismicity of the Northern Bartlett Springs Fault Zone ....................................11 Fault Creep along the Northern Bartlett Springs Fault ......................................13 Southern Bartlett Springs Fault Zone ............................................................................15 Faults of the Middle Mountain and Sanhedrin Mountain Areas ..............................16 Faults of the Clear Lake Area ..........................................................................................16 Faults Northeast of the Bartlett Springs Fault Zone ...................................................17 Major Folds ..........................................................................................................................................18 Wilbur Springs Dextral Hook ...................................................................................................18 Antiforms and Synforms ..................................................................................................19 Bartlett Springs Synform ........................................................................................19 Wilbur Springs Antiform .........................................................................................20 Pacific Ridge Antiform ............................................................................................20 Bartlett Mountain Antiform ....................................................................................20 Middle Mountain Synform ......................................................................................20 Description of Map Units ...........................................................................................................................20 Unconsolidated Deposits ..................................................................................................................20 Alluvial Deposits..................................................................................................................................20 Terrace Deposits .................................................................................................................................21 Fan Deposits ........................................................................................................................................21 Glacial Deposits ..................................................................................................................................21 Spring Deposits ...................................................................................................................................21 Volcanic Rocks ....................................................................................................................................22 Fluvial and Lacustrine Fill ..................................................................................................................22 iii Marine Overlap Deposits ...................................................................................................................22 Great Valley Complex ........................................................................................................................22 Elder Creek Terrane ...................................................................................................................22 Coast Range Ophiolite ........................................................................................................................24 Franciscan Complex ...........................................................................................................................25 Central Belt .................................................................................................................................25 Central Belt Mélange terrane .........................................................................................25 Eastern Belt.................................................................................................................................26 Yolla Bolly terrane .............................................................................................................26 Pickett Peak .......................................................................................................................27 Medicine Pass ...................................................................................................................27 References Cited..........................................................................................................................................27 Figures 1. Map showing location of the map area, the Lake Pillsbury
Load more

Recommended publications
  • Chapter 5: Parks, Recreation, and Open Space
    5 Parks, Recreation, and Open Space This chapter is a guide to the parks, recreation and open space resources in Humboldt County. Humboldt is home to recreational, park, and open space resources of statewide, nationwide, and even global significance. With this in mind, the first two sections describe these resources, while the final section addresses existing policies and policy issues identified during Phase I along with policy options that respond to them. 5.1 PARK AND RECREATION FACILITIES Humboldt County has a wealth of outdoor recreational opportunities and areas of incomparable value and unsurpassed beauty. More than twenty percent of the county’s 2.3 million acres are protected open space, forests, and recreation areas. Within the county boundaries, there are 4 federal parks and beaches, 10 state parks (3 of which are encompassed by Redwood National Park), 16 county parks and beaches, recreational areas and reserves, and National Parkland and National Forest land. These areas contribute to the quality of life in Humboldt County and provide needed recreation opportunities for residents of neighboring counties and from all over the world as well. Parklands are important elements of the Humboldt economy through both their role in the timber industry and the tourist industry. As tourism eclipses timber as the stronghold of Humboldt’s economy, parks and recreational resources will prove of greater and greater value to Humboldt’s future. The natural qualities of Humboldt County attract a great many people from outside the county. The tourist industry and demand for park resources in Humboldt are linked to the accessibility of parkland.
    [Show full text]
  • Late Cenozoic Tectonics of the Central and Southern Coast Ranges of California
    OVERVIEW Late Cenozoic tectonics of the central and southern Coast Ranges of California Benjamin M. Page* Department of Geological and Environmental Sciences, Stanford University, Stanford, California 94305-2115 George A. Thompson† Department of Geophysics, Stanford University, Stanford, California 94305-2215 Robert G. Coleman Department of Geological and Environmental Sciences, Stanford University, Stanford, California 94305-2115 ABSTRACT within the Coast Ranges is ascribed in large Taliaferro (e.g., 1943). A prodigious amount of part to the well-established change in plate mo- geologic mapping by T. W. Dibblee, Jr., pre- The central and southern Coast Ranges tions at about 3.5 Ma. sented the areal geology in a form that made gen- of California coincide with the broad Pa- eral interpretations possible. E. H. Bailey, W. P. cific–North American plate boundary. The INTRODUCTION Irwin, D. L. Jones, M. C. Blake, and R. J. ranges formed during the transform regime, McLaughlin of the U.S. Geological Survey and but show little direct mechanical relation to The California Coast Ranges province encom- W. R. Dickinson are among many who have con- strike-slip faulting. After late Miocene defor- passes a system of elongate mountains and inter- tributed enormously to the present understanding mation, two recent generations of range build- vening valleys collectively extending southeast- of the Coast Ranges. Representative references ing occurred: (1) folding and thrusting, begin- ward from the latitude of Cape Mendocino (or by these and many other individuals were cited in ning ca. 3.5 Ma and increasing at 0.4 Ma, and beyond) to the Transverse Ranges. This paper Page (1981).
    [Show full text]
  • Geologic Gems of California's State Parks
    STATE OF CALIFORNIA – EDMUND G. BROWN JR., GOVERNOR NATURAL RESOURCES AGENCY – JOHN LAIRD, SECRETARY CALIFORNIA GEOLOGICAL SURVEY DEPARTMENT OF PARKS AND RECREATION – LISA MANGAT, DIRECTOR JOHN D. PARRISH, Ph.D., STATE GEOLOGIST DEPARTMENT OF CONSERVATION – DAVID BUNN, DIRECTOR PLATE 1 The rugged cliffs of Del Norte Coast Redwoods State Park are composed of some of California’s Bio-regions the most tortured, twisted, and mobile rocks of the North American continent. The California’s Geomorphic Provinces rocks are mostly buried beneath soils and covered by vigorous redwood forests, which thrive in a climate famous for summer fog and powerful winter storms. The rocks only reveal themselves in steep stream banks, along road and trail cut banks, along the precipitous coastal cliffs and offshore in the form of towering rock monuments or sea stacks. (Photograph by CalTrans staff.) Few of California’s State parks display impressive monoliths adorned like a Patrick’s Point State Park displays a snapshot of geologic processes that have castle with towering spires and few permit rock climbing. Castle Crags State shaped the face of western North America, and that continue today. The rocks Park is an exception. The scenic beauty is best enjoyed from a distant exposed in the seacliffs and offshore represent dynamic interplay between the vantage point where one can see the range of surrounding landforms. The The Klamath Mountains consist of several rugged ranges and deep canyons. Klamath/North Coast Bioregion San Joaquin Valley Colorado Desert subducting oceanic tectonic plate (Gorda Plate) and the continental North American monolith and its surroundings are a microcosm of the Klamath Mountains The mountains reach elevations of 6,000 to 8,000 feet.
    [Show full text]
  • Multi-Stage Origin of the Coast Range Ophiolite, California: Implications for the Life Cycle of Supra-Subduction Zone Ophiolites
    International Geology Review, Vol. 46, 2004, p. 289–315. Copyright © 2004 by V. H. Winston & Son, Inc. All rights reserved. Multi-Stage Origin of the Coast Range Ophiolite, California: Implications for the Life Cycle of Supra-Subduction Zone Ophiolites JOHN W. S HERVAIS,1 Department of Geology, Utah State University, 4505 Old Main Hill, Logan, Utah 84322-4505 DAVID L. KIMBROUGH, Department of Geological Sciences, San Diego State University, San Diego California 92182-1020 PAUL RENNE, Berkeley Geochronology Center, 2455 Ridge Road, Berkeley, California 94709 and Department of Earth and Planetary Science, University of California, Berkeley, California 94720 BARRY B. HANAN, Department of Geological Sciences, San Diego State University, San Diego California 92182-1020 BENITA MURCHEY, United States Geological Survey, 345 Middlefield Road, Menlo Park California 94025 CAMERON A. SNOW, Department of Geology, Utah State University, 4505 Old Main Hill, Logan, Utah 84322-4505 and Department of Geological and Environmental Sciences, Stanford University, Stanford, California 94305 MARCHELL M. ZOGLMAN SCHUMAN,2 AND JOE BEAMAN3 Department of Geological Sciences, University of South Carolina, Columbia, South Carolina 29208 Abstract The Coast Range ophiolite of California is one of the most extensive ophiolite terranes in North America, extending over 700 km from the northernmost Sacramento Valley to the southern Trans- verse Ranges in central California. This ophiolite, and other ophiolite remnants with similar mid- Jurassic ages, represent a major but short-lived episode of oceanic crust formation that affected much of western North America. The history of this ophiolite is important for models of the tectonic evolution of western North America during the Mesozoic, and a range of conflicting interpretations have arisen.
    [Show full text]
  • Paleontology and Stratigraphy of Eocene Rocks at Pulali Point, Jefferson County, Eastern Olympic Peninsula, Washington
    PALEONTOLOGY AND STRATIGRAPHY OF EOCENE ROCKS AT PULALI POINT, JEFFERSON COUNTY, EASTERN OLYMPIC PENINSULA, WASHINGTON by RICHARD L. SQUIRES, JAMES L. GOEDERT, and KEITH L. KALER WASHINGTON DIVISION OF GEOLOGY AND EARTH RESOURCES REPORT OF INVESTIGATIONS 31 1992 ., WASHINGTON STATE DEPARTMENT OF Natural Resources Brian Boyle • Commhstoner of Public Lands An Steo_r0$ - Superv1sor Division ol Geology and Earth Resources Raymond Lcmnanls. State Geologlsl PALEONTOLOGY AND STRATIGRAPHY OF EOCENE ROCKS AT PULALI POINT, JEFFERSON COUNTY, EASTERN OLYMPIC PENINSULA, WASHINGTON by RICHARD L. SQUIRES, JAMES L. GOEDERT, AND KEITH L. KALER WASHINGTON DIVISION OF GEOLOGY AND EARTH RESOURCES REPORT OF INVESTIGATIONS 31 1992 W>.SHING'TON STAT1r OEPARTMDIT or Natural Resources 8ncll) Bov,. · COmmmioner ot Pu!xk: tancb M $i.atni; S\lp$1'WOJ' DtY!llcn 01 Gtology ahCS £artti ~ Raymond l.mlMn.:I ~Geologist Cover: From left, ?Falsifusus marysvillensis; Pachycrommium clarki; large bivalve, Veneri­ cardia hornii s.s.; Delectopecten cf. D. vancouverensis sanjuanensis; Turritella uvasana hendoni. These specimens are shown at 150 percent of the dimensions on Plates 1 and 3. Use of trade, product, or firm names in this report is for descriptive purposes only and does not consitute endorsement by the Washington Division of Geology and Earth Resources. This report is available from: Publications Washington Department of Natural Resources Division of Geology and Earth Resources P.O. Box 47007 Olympia, WA 98504-7007 Price $ 1.85 Tax (Stale residenl.t only) .15 Total $ 2.00 Mail orders must be prepaid; please add $1.00 to each order for postage and handling. Make checks payable to the Department of Natural Resources.
    [Show full text]
  • Annual Report 2014
    Town of Waterville Valley Annual Report 2014 For the Fiscal Year Ended December 31, 2014 WATERVILLE VALLEY INFORMATION “The Town at the End of the Road” Population………………………………………………………………………………………………………………….405 Date of Incorporation……………………………………………………………………………………………….1829 Registered Voters……………………………………………………………………………………………………….278 Area…………………………………………………………………………………………………….40,811 Total Acres *White Mountain National Forest 40,225 *Privately owned Property 585 County………………………………………………………………………………………………………………….Grafton Governor………………………………………………………………………………………………....Maggie Hassan Executive Councilor, District 1…………………………………………………………………..Joseph Kenney State Senator, District 3…………………………………………………………………………...…...Jeb Bradley State Representative, Grafton District 5………………………………………………..…Edmond Gionet U.S. Congressman, District 2…………………………………………………………….............Annie Kuster U.S. Senators………………………………………………………………………Jeanne Shaheen, Kelly Ayotte Electric Company………………………………………………………..NH Electric Cooperative 536-1800 Telephone Company…………………………………………………………………...Time Warner, Fairpoint Waterville Valley Post Office……………………………………………………………………...603-236-8414 Time Warner Cable………………………………………………………………………………….1-888-683-1000 Waterville Valley Town Offices………………………………………………………………………….236-4730 WV-DPS Police and Fire……………………………………………………………………………………..236-8809 **FOR EMERGENCIES CALL 911** Incorporated in 1829, Waterville Valley is a year-round resort community located in the heart of New Hampshire's White Mountain National Forest, conveniently located only 2
    [Show full text]
  • Major Chemical Characteristics of Mesozoic Coast Range Ophiolite in California
    JOURNAL OF OF THE U.S. GEOLOGICAL SURVEY NOVEMBER-DECEMBER 1974 VOLUME 2, NUMBER 6 Scientific notes and summaries of investigations in geology, hydrology, and related fields +r U«/ fc/ U.S. DEPARTMENT OF THE INTERIOR UNITED STATES DEPARTMENT OF THE INTERIOR ROGERS C. B. MORTON, Secretary GEOLOGICAL SURVEY V. E. McKelvey, Director For sale by the Superintendent of Documents, U.S. Government Printing Office, Washington, DC The Journal of Research is pub­ Correspondence and inquiries concerning the Jour­ 20402. Order by SD Catalog No. lished every 2 months by the U.S. nal (other than subscription inquiries and address JRGS. Annual subscription rate Geological Survey. It contains changes) should be directed to the Journal of Re­ $15.50 (plus $3.75 for foreign mail­ papers by members of the Geologi­ search, Publications Division, U.S. Geological Survey, ing). Single copy $2.75. Make cal Survey and their professional National Center 321, Reston, VA 22092. checks or money orders payable to colleagues on geologic, hydrologic, the Superintendent of Documents. topographic, and other scientific Papers for the Journal should be submitted through Send all subscription inquiries and technical subjects. regular Division publication channels. and address changes to the Superin­ tendent of Documents at the above address. Purchase orders should not be sent to the U.S. Geological Survey The Secretary of the Interior has determined that the publication of this periodical is library. necessary in the transaction of the public business required by law of this Department. Library of Congress Catalog-card Use of funds for printing this periodical has been approved by the Director of the Office No.
    [Show full text]
  • Bigbig Sursur
    CalCal PolyPoly -- PomonaPomona GeologyGeology ClubClub SpringSpring 20032003 FFieldield TTriprip BigBig SurSur David R. Jessey Randal E. Burns Leianna L. Michalka Danielle M. Wall ACKNOWLEDGEMENT The authors of this field guide would like to express their appreciation and sincere thanks to the Peninsula Geologic Society, the California Geological Survey and Caltrans. Without their excellent publications this guide would not have been possible. We apologize for any errors made through exclusion or addition of trip field stops. For more detailed descriptions please see the following: Zatkin, Robert (ed.), 2000, Salinia/Nacimiento Amalgamated Terrane Big Sur Coast, Central California, Peninsula Geological Society Spring Field Trip 2000 Guidebook, 214 p. Wills, C.J., Manson, M.W., Brown, K.D., Davenport, C.W. and Domrose, C.J., 2001, LANDSLIDES IN THE HIGHWAY 1 CORRIDOR: GEOLOGY AND SLOPE STABILITY ALONG THE BIG SUR COAST, California Department of Conservation Division of Mines & Geology, 43 p. 0 122 0 00' 122 0 45' 121 30 Qal Peninsula Geological Society Qal G a b i Qt la Field Trip to Salina/Nacimento 1 n R S a A n L Big Sur Coast, Central California I g N qd A e S R Qt IV E Salinas R S a lin a s Qs V Qal 101 a Qs Monterey Qc lle Qt Qp y pgm Tm Qm Seaside pgm EXPLANATION Qt Chualar Qp Qt UNCONSOLIDATED Tm pgm SEDIMENTS Qp Carmel Qal sur Qs Qal Alluvium qd CARMEL RIVER Tm Qal Point sur Qs Dune Sand Tm Lobos pgm 0 S 0 36 30 ie ' r 36 30' pgm ra Qt Quaternary non-marine d CARMEL e S terrace deposits VALLEY a Qal lin a Qt Pleistocene non-marine Tm pgm s Qc 1 Tm Tula qd rcit Qp Plio-Pleistocene non-marine qd os F ault Qm Pleistocene marine Terrace sur sur deposits qd Tm COVER ROCKS pgm qd Tm Monterey Formation, mostly qm pgm qm pgm marine biogenic and sur pgm clastic sediments middle to qdp sur qd late Miocene in age.
    [Show full text]
  • Dimerelloid Rhynchonellide Brachiopods in the Lower Jurassic of the Engadine (Canton Graubünden, National Park, Switzerland)
    1661-8726/08/010203–20 Swiss J. Geosci. 101 (2008) 203–222 DOI 10.1007/s00015-008-1250-8 Birkhäuser Verlag, Basel, 2008 Dimerelloid rhynchonellide brachiopods in the Lower Jurassic of the Engadine (Canton Graubünden, National Park, Switzerland) HEINZ SULSER & HEINZ FURRER * Key words: brachiopoda, Sulcirostra, Carapezzia, new species, Lower Jurassic, Austroalpine ABSTRACT ZUSAMMENFASSUNG New brachiopods (Dimerelloidea, Rhynchonellida) from Lower Jurassic Neue Brachiopoden (Dimerelloidea, Rhynchonellida) aus unterjurassischen (?lower Hettangian) hemipelagic sediments of the Swiss National Park in hemipelagischen Sedimenten (?unteres Hettangian) des Schweizerischen Na- south-eastern Engadine are described: Sulcirostra doesseggeri sp. nov. and tionalparks im südöstlichen Engadin werden als Sulcirostra doesseggeri sp. Carapezzia engadinensis sp. nov. Sulcirostra doesseggeri is externally similar to nov. und Carapezzia engadinensis sp. nov. beschrieben. Sulcirostra doesseggeri S. fuggeri (FRAUSCHER 1883), a dubious species, that could not be included in ist äusserlich S. fuggeri (FRAUSCHER 1883) ähnlich, einer zweifelhaften Spezies, a comparative study, because relevant samples no longer exist. A single speci- die nicht in eine vergleichende Untersuchung einbezogen werden konnte, weil men was tentatively assigned to Sulcirostra ?zitteli (BÖSE 1894) by comparison kein relevantes Material mehr vorhanden ist. Ein einzelnes Exemplar wird als of its external morphology with S. zitteli from the type locality. The partly Sulcirostra ?zitteli (BÖSE 1894) bezeichnet, im Vergleich mit der Aussenmor- silicified brachiopods are associated with sponge spicules, radiolarians and phologie von S. zitteli der Typuslokalität. Die teilweise silizifizierten Brachio- crinoid ossicles. Macrofossils are rare: dictyid sponges, gastropods, bivalves, poden waren mit Schwammnadeln, Radiolarien und Crinoiden-Stielgliedern crustaceans, shark teeth and scales of an actinopterygian fish. The Lower Ju- assoziiert.
    [Show full text]
  • California Floras, Manuals, and Checklists: a Bibliography
    Humboldt State University Digital Commons @ Humboldt State University Botanical Studies Open Educational Resources and Data 2019 California Floras, Manuals, and Checklists: A Bibliography James P. Smith Jr Humboldt State University, [email protected] Follow this and additional works at: https://digitalcommons.humboldt.edu/botany_jps Part of the Botany Commons Recommended Citation Smith, James P. Jr, "California Floras, Manuals, and Checklists: A Bibliography" (2019). Botanical Studies. 70. https://digitalcommons.humboldt.edu/botany_jps/70 This Flora of California is brought to you for free and open access by the Open Educational Resources and Data at Digital Commons @ Humboldt State University. It has been accepted for inclusion in Botanical Studies by an authorized administrator of Digital Commons @ Humboldt State University. For more information, please contact [email protected]. CALIFORNIA FLORAS, MANUALS, AND CHECKLISTS Literature on the Identification and Uses of California Vascular Plants Compiled by James P. Smith, Jr. Professor Emeritus of Botany Department of Biological Sciences Humboldt State University Arcata, California 21st Edition – 14 November 2019 T A B L E O F C O N T E N T S Introduction . 1 1: North American & U. S. Regional Floras. 2 2: California Statewide Floras . 4 3: California Regional Floras . 6 Northern California Sierra Nevada & Eastern California San Francisco Bay, & Central Coast Central Valley & Central California Southern California 4: National Parks, Forests, Monuments, Etc.. 15 5: State Parks and Other Sites . 23 6: County and Local Floras . 27 7: Selected Subjects. 56 Endemic Plants Rare and Endangered Plants Extinct Aquatic Plants & Vernal Pools Cacti Carnivorous Plants Conifers Ferns & Fern Allies Flowering Trees & Shrubs Grasses Orchids Ornamentals Weeds Medicinal Plants Poisonous Plants Useful Plants & Ethnobotanical Studies Wild Edible Plants 8: Sources .
    [Show full text]
  • Development and Implications of a Sediment Budget for the Upper Elk River Watershed, Humboldt County1
    Proceedings of the Coast Redwood Science Symposium—2016 Development and Implications of a Sediment Budget for the Upper Elk River Watershed, Humboldt County1 2 3 3 3 Lee H. MacDonald, Michael W. Miles, Shane Beach, Nicolas M. Harrison, 4 5 6 Matthew R. House, Patrick Belmont, and Ken L. Ferrier Abstract A number of watersheds on the North Coast of California have been designated as sediment impaired under the Clean Water Act, including the 112 km2 upper Elk River watershed that flows into Humboldt Bay just south of Eureka. The objectives of this paper are to: 1) briefly explain the geomorphic context and anthropogenic uses of the Elk River watershed; 2) develop a process-based sediment budget for the upper watershed, including an explicit assessment of the uncertainties in each component; and 3) use the results to help guide future management and restoration. Natural (background) sediment inputs are believed to be relatively high due to high uplift rates, weak Miocene-Pliocene bedrock materials, steep slopes, high rainfall, and resulting high landslide frequency. The primary land use in the upper watershed is industrial timberlands, and intensive logging in the 1980s and 1990s greatly increased sediment production rates and downstream aggradation. Road improvements and major changes in forest practices have caused anthropogenic sediment inputs to drop by roughly an order of magnitude since the 1990s. Suspended sediment yields plotted against annual maximum peak flows indicate a decline since 2013, suggesting that the legacy pulse of sediment is now moving into the lower portions of the watershed and that improved management practices are having a beneficial effect.
    [Show full text]
  • Volume 12, 1946 1946 INDNX to GEOLOGIC,\L F::EWS-L1'l'l'er Volume 12 Compiled by John Eliot Allen, and 1!:1-Iart If
    G&lLOGICAL SOCIETY NEWS LETTER Volume 12, 1946 1946 INDNX to GEOLOGIC,\L f::EWS-L1'l'l'ER Volume 12 Compiled by John Eliot Allen, and 1!:1-iart If.. Baldwin ·~----------------------------- Subject Index Annual Fanquet Address: J. E. Allen, pp. 36-37 Annual Banquet Photo: O. E. Stanley, opposite p. 44 Annual Banquet Speaker, Dr. L. W. Staples: E. !!. Baldwin, ·p.38 Annual Picnic: J. E. Allen, pp. 88-89 Annual Picnic l'hoto: o. E. Stanley, opposite p. 108 Annual Report, Histoz•ical Committee: 0, E. Stanley, p. 27 " • Library Committee: M. Hughes, p. 33 '' " Museum Committee: J. C. Stevens, pp. 4C-41 " " Research Committee: E, 11. Baldwin, pp. 41-42 " " Secretary: · A. Henley, p. 28 " " Treasurer: H. M. Stockwell, p. 32 • " Trip Committee: II. B. Schminky, p. 33 Bauxite field trip: R. S. Mason, p. 49 Bend trip, hiehlights of the: u. Shepard, p. 78 Ily-Laws of the G, S. O. C.: pp. 96-102 Climate and post-e-lacial fore&t succession in the Oregon Cascades by H. P. Ilan- sen--A reviev.: J. E. Allen, pp. 104-105 Columbia Gorge, fossil ¥:cods of the: G. F. Beck, pp. 46-47 Committee Appointments, 1946: J, E. Allen, p. 27 Composition of ocean water--reprint: p. 59 Condon, Thomas, en Oregon pioneer: E. C, ~cCornack, pp. 69-72, 82-84; preamble by W. C. Adams, p. 69 Condon, History of the Liberty ship SS Thomas: S. E. S., p. 15 Constitution, preamble: J. E. Allen, p. 96 Sarthquake--'pertial reprint from Ore-Bin; p. 60 Eastern Oregon, Geologist's weekend in ; W.
    [Show full text]