DOCSLIB.ORG

Geology of the Ore Deposits of Kennecott, Alaska

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Geology of the Ore Deposits of Kennecott, Alaska ECONOMIC GEOLOGY WITH WHICH IS INCORPORATED THE AMERICAN GEOLOGIST VOL. XV JANUARY-FEBRUARY, 92o NO. I GEOLOGY OF THE ORE DEPOSITS OF KENNECOTT, ALASKA. ALAN M. BATEMAN AND D. H. MCLAUGItLIN. 1 CONTENTS. PAGE. INTRODUCTION ......................................................... 2 TOPOGRAPHY.......................................................... 4 ROCK FORMATIONS.................................................... 5 STRUCTURE ........................................................... I PHYSIOGRAPHICDEVELOPMENT ......................................... I•:, ORE DEPOSITS........................................................ General .......................................................... I7' Character of ore ................................................. I8; Types of deposits ................................................ I8. Mineralization in greenstone .............................. 19, Mineralization in limestone ................................... 20., Talus ore deposit ......................... : ................... 23, Glacier ore deposit ........................................... 23; Structural relations ............................................... 24J. Relation of mineralization to rocks ............................ 24- Behavior of fissures .......................................... 26 Relation of mineralization to fractures ........................ 27 Relation of mineralization to folds ............................ 29 Relation of mineralization to faults ............................ 3o Shapes'and sizes of ore bodies ................................ Relation to surface ........................................... 3t x This paper embodies the result's of field and laboratory studies of the Kennecott deposits carried on at various times during the last five years. The authors were together at Kennecott in the field seasonof I915, when the work was initiated in co6peration wit'h the Secondary Enrichment Investi- gation. Field work was continued by the first named author during the four following seas.ohsin his capacity of consulting geologist to the Kennecofi• Copper Corporation, while most of the det'ailed microscopic work was done. in the laboratoryby the other, in connectionwith researchfor the Secondary. Enrichment Investigation. .ALAN M. BATEMAN AND D. H. McL.,4UGHLIN. Distributionof ore bodies........................................ 33 Alteration of host rocks .......................................... 34 Mineralogy and mineralography .................................. 35 OXm•TIONo7 OREDEPosiTs .......................................... 44 General .......................................................... 44 Minerals due to oxidation ........................................ 45 Distributionand depthof oxidation ............................... 48 Relation of oxidationto structures................................ 49 Relation to water level and climate ................................ 50 Age of oxidation ................................................. 53 THEORETICALCONSIDERATIONS .......................................... 54 Origin of fissures................................................. 54 Suggestedhypothesis ......................................... 54 Origin of mineralization .......................................... 57 Source of metals in limestone ................................ .. 57 Origin of copper in greenstone ................................ 59 Agents of transportation ..................................... 6I • Met'hods of deposition ........................................ 65 Primary or secondaryorigin of the chalcocite ...................... 66 Experimental evidence ........................................ 67 Mineralographic evidence ..................................... 67 Field evidence ................................................ 70 Discussion of evidence ........................................ 73 Conclusions .................................................. 77 SUMMARIZEDCONCLUSION OF ORIGIN OF ORE DEPOSITS................... 77 INTRODUCTION. General.--The copper depositsof the famous Bonanza and Jumbo Mines at Kennecott,Alaska, are unique for the character of their ores and 'their purity and size. Their occurrencepre~ sents many peculiar and interestingfeatures, and the origin of the great massesof .chalcocitehas long been a puzzle. Their ,decipheringinvo,lves the origin of f,racturesunusual in form; of a peculiar kind of primary mineralizationunparalleled in other deposits;of a sourceof metals not customarilyconsidered, as well as agentsof transportationbut seldomreferred to. No con- clusionscan be reachedwithout carefully weighing the primary or secondaryorigin of the chalcocite,and much of interest is gained regarding the distribution of oxidation and groun4water. It is with theseproblems that the paper deals,and' the facts and conclusionspresented, in the following pages are the result of a studyextending over a periodof five seasons,during which time the developmentof the .ore 'bodieshas been carefully followed and their detailsaccurately mapped. Location.--The Bonanzaand Jumbo Mines, the most impor- GEOLOGYOFORE DEPOSITS OFKENNECOTT, ALASKA. 3 tantof the mining properties ofthe Kennecott Copper Corp., are situatedatKenneco.tt, Alaska. (See Fig. •.) Thistown lies about200 miles northeast ofthe port of Cordova, onPrince Wil- liamSound, with which itis connected bythe, Copper River and NorthwesternRailro.ad, aroad which win.d,s around glaciers and is famousfor the difficulties of its co.nstruction. ThePort of 148ø lZ!G* zs o.... _ zs,•_. so ;? ,oo•,,•, FIG.I. Indexmap to show location ofCordova, Copper River and Kennecott. Cordovaisn, aviga'ble theyear around and the railroad maintains continuousservice.with Kennecott, suffering onlyslight interrup- tion,inevitable with its 1.ocation. Themines are one mile .apart and each one is at a distanceof threemiles from the town of Kennecott 2and 4,000 feet above it, at anelevation of about 6,000 feet. Theyare connected with themill in the town by a•rial tramways. 2The U.S. Geol. Surv. terminology givesthe spelling asKennicott butthe postoffice and company name are spelt as. Kennecott. Asthe latter is com- monusage it is followedin thispaper. ALAN M. BATEMAN AND D. H. McLAUGHLIN. •'tcknowledcdments.--Wetake pleasurein acknowledgingthe courtesiesand help renderedby the staff at Kennecottin •9•5, and the aid receivedfrom the geol.ogic maps prepared by W. E. Dunkle and H. D. Smith. The first named writer further records with appreciationthe benefit receivedin the seasonssince •9•5 from discussionswœth E. T. Stannard, Wm. Douglas, H. D. Smith, D.. C. Hoyt, and D. D. Irwin, and the helpfulnesso4 their information concerningthe detailed developmentof the ore bodies. Acknowledgmentis .due to Mr. StephenBirch, presi- dentof the.company, for placingall facilitiesat our disposaland for his permissi.onto publishthis material. The painstakingareal work by the membersof the United StatesGeological Survey facilitated 'our observations and' deduc- tions, and we ackr•owledgemore than the mere sourcesof the information recorded to the individual members in the foot- notes. To ProfessorL. C. Grato.nwe especiallydesire to record our grateful thanks for his many discussionsand sympathetic criticisms. TOPOGRAPHY. The regionin the vicinityof the minesis oneof pronounced relief with high, steep-sidedmountains, rugged in detail, rising from KennecottValley (Plate I., ,z/). The valley itself .isoccu- piedby the Kennecottglacier, which has a width .of aboutthree miles at the town and extendsnorthwestward about twenty-four miles to its gathering groundson Mt. Blackburn, •6,•4o feet, and Mr. Regal, about •4,ooo (Plate I., B). The mountainsides on the Kennecottedge of the glacierrise steeplyto the sharpdivide of Kermecottspur at an elevationof about 7,ooo feet. The Spur juts southward fr.om the main WrangelMountains and is limitedon the westby KennecottVal- ß ley and on the eastby McCarthy,Creek, and risesfrom an ele- vation of 2,000 feet at the glacierand 2,650 feet at McCarthy Creek,to n'early7,0o0 feet (Fig. 3). The top of the divide where occupiedby the Chitisto,nelimestone is serratedinto per- pendicularpinnacles and hoodooforms of the shatteredbrittle PLATE I. ECONOMIC GEOLOGY. VOL. XV. .____-- a. Kennecott spur and town of Kennecott, showing topography and location of mines (+). b. Kennecott glacier. Mr. Blackburn in background and greenstone-limestone contact at right. c. "Hoodoo" topography developed on fractured limestone adjacent to Bonanza Mine. PLATE II. ECONOMIC GEOLOGY. VOL. XV. a. Contact betweengreenstone (dark) and limestone(light). Jumbo Mine at right. b. Greenstone-limestonecontact. l•ormal contact at left, down-faulted against greenstone. c. Quartz-diorite porphyry with inclusions of black shale of Kennecott formation, GEOLOGY OF ORE DEPOSITS OF KENNECOTT, ALASKA. 5 rock, resemblingthe DolomiteAlps (Plate I., C). Great talus slopes,at the angleof repose,reach down hundreds of feet below thepinnacles. The iower slopes underlain by thegreenstone, are less rough, with occasionalbenches and cliffs. The areas of porphyryweather to smoothsteep slopes covered by talus. The mineslie approximatelyI,OOO feet •belowthe highestpoint of the spur. The slopes.are scored by deep,steep-sided, V-shaped tributary gulches.c'on. taining dashingstreamlets which empty into the main valley at the edge of the glacier. The headsof these gulchescontain small hanging glaciers,.rock glac.iers,a or talus slopes. The Jumbo Mine is situatedin a basin at the edgeof
Load more

Recommended publications
  • RESOURCES NATURAL Divisto~OF Geologicala CEOPHYSKAL SURVEYS RESOURCES
    Published by STATEOF ALASKA Abska Department of DEPARTMENTOF NATURAL RESOURCES NATURAL Divisto~OF GEOLOGICALa CEOPHYSKAL SURVEYS RESOURCES 1996 /rice: $5.00 - -- .-. -- -- - -A-- - - - - - - - Information Circular 11 PUBLICATIONSCATALOG OF THE DIVISION OF GEOLOGICAL& GEOPHYSICAL SURVEYS Fourth Edition Published by STATEOF ALASKA DEPARTMENTOF NATURAL RESOURCES DIVISIONOF GEOLOGICAL& GEOPHYSICAL SURVEYS DEDICATION All of us who have had the pleasure of working with Roberta (Bobbi) Mann are indeed fortunate. Without exception, we have found her to be industrious, dedicated, efficient, and of unflagging good humor. Fully half of the publications listed in this brochure couldn't have been produced without her. STATE OF ALASKA For over 20 years, Bobbi has routinely typed (and corrected) Tony Knowles, Governor all the sesquipedalian buzzwords in the geologist's lexicon, from allochthonous to zeugogeosyncline (with stops at DEPARTMENT OF hypabyssal and poikiloblastic)-without having even the NATURAL RESOURCES remotest idea of their meaning. John T. Shively, Commissioner DIVISION OF GEOLOGICAL & Such zeal. Bobbi has spent most of her adult life typing error- GEOPHYSICAL SURVEYS free documents about an arcane subject she knows virtually Milton A. Wiltse, Acting Director and nothing about. If, at the end of her career, someone would ask State Geologist her what she spent the last few decades typing, I'm positive Bobbi would shyly smile and say, "I'm not really sure. Some- Publication of DCCS reports is required by thing about rocks." Alaska Statute 41, "to determine the poten- tial ofAlaskan land for production of metals, minerals, fuels, and geothermal resources; Now THAT'S dedication. the location and supplies of groundwater and construction materials; the potential geologic hazardsto buildings, roads, bridges, and other installations and structures; and .
    [Show full text]
  • P1616 Text-Only PDF File
    A Geologic Guide to Wrangell–Saint Elias National Park and Preserve, Alaska A Tectonic Collage of Northbound Terranes By Gary R. Winkler1 With contributions by Edward M. MacKevett, Jr.,2 George Plafker,3 Donald H. Richter,4 Danny S. Rosenkrans,5 and Henry R. Schmoll1 Introduction region—his explorations of Malaspina Glacier and Mt. St. Elias—characterized the vast mountains and glaciers whose realms he invaded with a sense of astonishment. His descrip­ Wrangell–Saint Elias National Park and Preserve (fig. tions are filled with superlatives. In the ensuing 100+ years, 6), the largest unit in the U.S. National Park System, earth scientists have learned much more about the geologic encompasses nearly 13.2 million acres of geological won­ evolution of the parklands, but the possibility of astonishment derments. Furthermore, its geologic makeup is shared with still is with us as we unravel the results of continuing tectonic contiguous Tetlin National Wildlife Refuge in Alaska, Kluane processes along the south-central Alaska continental margin. National Park and Game Sanctuary in the Yukon Territory, the Russell’s superlatives are justified: Wrangell–Saint Elias Alsek-Tatshenshini Provincial Park in British Columbia, the is, indeed, an awesome collage of geologic terranes. Most Cordova district of Chugach National Forest and the Yakutat wonderful has been the continuing discovery that the disparate district of Tongass National Forest, and Glacier Bay National terranes are, like us, invaders of a sort with unique trajectories Park and Preserve at the north end of Alaska’s panhan­ and timelines marking their northward journeys to arrive in dle—shared landscapes of awesome dimensions and classic today’s parklands.
    [Show full text]
  • Wrangell-St. Elias National Park and Preserve Visitor Study Summer 1995
    Wrangell-St. Elias National Park and Preserve Visitor Study Summer 1995 Report 77 Visitor Services Project Cooperative Park Studies Unit Visitor Services Project Wrangell-St. Elias National Park and Preserve Visitor Study Margaret Littlejohn Report 77 January 1996 Margaret Littlejohn is VSP Coordinator, National Park and Preserve Service based at the Cooperative Park Studies Unit, University of Idaho. I thank Diane Jung, Maria Gillette, Glen Gill and the staff of Wrangell-St. Elias National Park and Preserve for their assistance with this study. The VSP acknowledges the Public Opinion Lab of the Social and Economic Sciences Research Center, Washington State University, for its technical assistance. Visitor Services Project Wrangell-St. Elias National Park and Preserve Report Summary • This report describes part of the results of a visitor study at Wrangell-St. Elias National Park and Preserve during July 12-18, 1995. A total of 531 questionnaires were distributed to visitors. Visitors returned 444 questionnaires for an 84% response rate. • This report profiles Wrangell-St. Elias visitors. A separate appendix contains visitors' comments about their visit; this report and the appendix include a summary of visitors' comments. • Fifty-five percent of the visitors were in family groups; 20% were in groups of friends. Forty-nine percent of Wrangell-St. Elias visitors were in groups of two. Most visitors (56%) were aged 26- 55. • Among Wrangell-St. Elias visitors, 11% were international visitors. Forty percent of those visitors were from Germany. United States visitors were from Alaska (31%), California (7%), Florida (5%) and 43 other states. • Almost two-thirds of Wrangell-St.
    [Show full text]
  • Hydrologic and Mass-Movement Hazards Near Mccarthy Wrangell-St
    Hydrologic and Mass-Movement Hazards near McCarthy Wrangell-St. Elias National Park and Preserve, Alaska By Stanley H. Jones and Roy L Glass U.S. GEOLOGICAL SURVEY Water-Resources Investigations Report 93-4078 Prepared in cooperation with the NATIONAL PARK SERVICE Anchorage, Alaska 1993 U.S. DEPARTMENT OF THE INTERIOR BRUCE BABBITT, Secretary U.S. GEOLOGICAL SURVEY ROBERT M. HIRSCH, Acting Director For additional information write to: Copies of this report may be purchased from: District Chief U.S. Geological Survey U.S. Geological Survey Earth Science Information Center 4230 University Drive, Suite 201 Open-File Reports Section Anchorage, Alaska 99508-4664 Box 25286, MS 517 Denver Federal Center Denver, Colorado 80225 CONTENTS Abstract ................................................................ 1 Introduction.............................................................. 1 Purpose and scope..................................................... 2 Acknowledgments..................................................... 2 Hydrology and climate...................................................... 3 Geology and geologic hazards................................................ 5 Bedrock............................................................. 5 Unconsolidated materials ............................................... 7 Alluvial and glacial deposits......................................... 7 Moraines........................................................ 7 Landslides....................................................... 7 Talus..........................................................
    [Show full text]
  • The Fate of Our
    November ll$ December 1996 The fate of our for8sts Research exposes past · , and possible future · of white ,.spruce in the Kennicott Valley page 7 .. ·· .. ·. .. ' ; ·: . ;· ._,.• •"'. Copper River A FIRST CLASS FLEET & More on the rolling stock! page 11 NorthWestern 6=====t •..,. _, ~~ Com•nsense ,... ., 4-L ')~ at.•ut ~~ ~V>' SIOWMOIILIIIG ·.· .,,. ~__... ·· · WI AGI MJJIIf · piaeia· ... ·... , ' ..... 21 ~. .~. PAGE 2 WRANGELL ST. EL1AS NEWS NOVEMBER & DECEMBER 1996 BY BONNIE KENYON reetings from chilly autumn as a roofer for Jim September 16 by Gilbert Merritt G McCarthy! It is October Miller's crew on the Kennicott of Nashville, TN. Someone had 18 and it was -16 degrees Mill Building. Mike has been in taken his red Trek 990 Mountain F. this morning - a sure sign and out of the valley since then, Bike in McCarthy from where he winter is here. often just to visit or to fly out to had locked it to a tree on the 9th. Our first snowfall occttrred the St. Elias range for a climbing The bike was valued at over on September 23. It didn't expedition, and this past $1,000. amount to much but it did summer, he collected data for his We offer our sympathy to succeed in spurring Rick and I on thesis. To fund his research, Mike Denise, F...athleen and Gilbert for to finish pulling the Brussel obtained grants from the their losses and pray these kinds sprouts and parsnips. We Untversity of Vermont and the of events will not be a norm in managed to get the garden all National Park Service, and also our town! harvested and tilled before 6 taught part-time for Jenny Subscribers Charlie and inches fell on October 7.
    [Show full text]
  • Community & Copper in a Wild Land
    Community & Copper in a Wild Land McCarthy, Kennecott and Wrangell-St. Elias National Park & Preserve, Alaska Shawn Olson Ben Shaine The Wrangell Mountains Center McCarthy Copyright © 2005 by Shawn Olson and Ben Shaine. Illustrations copyright as credited. Photos not otherwise attributed are by the authors. Published by The Wrangell Mountains Center. Front cover photo by Nancy Simmerman, 1974. Back cover photos: McCarthy street in winter: NPS; child sledding, harvesting garden: Ben Shaine; dog team, fall color, cutting salmon, splitting firewood: Gaia Thurston-Shaine; mountain goat: WMC collection; Kennecott mill, flowers, McCarthy garden, snowmachine sled repair, Root Glacier hikers: Nancy Simmerman. The Wrangell Mountains Center McCarthy 20 P.O. Box MXY Glennallen, Alaska 99588 (907) 554-4464 / [email protected] www.wrangells.org The Wrangell Mountains Center is a private, non-profit institute dedicated to environmental education, research, and arts in Alaska’s Wrangell-St. Elias National Park & Preserve. Contents Introduction 1 Maps 3 Rocks and Mountains 7 Glaciers 9 Climate 17 Ecosystems 21 Plants: Trees 29 Flowers and berries 33 Mosses and Lichens 37 Animals: Birds 38 Mammals 42 Fish 47 Hunting and Fishing 48 Human History: The Ahtna 51 Copper Discovery & Development 53 Kennecott 60 McCarthy 64 After the Mines Closed 67 Designation of the Park 69 A New Economy and a Growing Community 71 The Park Service at Kennecott 75 Entryway to the Wild Wrangells 78 Hikes in the McCarthy-Kennecott Area 80 Appendix: Species Lists 81 Bibliography 84 Kennicott Glacier panorama. (Wrangell Mountains Center collection) Preface and acknowledgements As a general introduction to its natural and cultural history, this Artistic contributions are many.
    [Show full text]
  • Wrangell Mountains Center
    Wrangell Mountains Center 907-244-7717 • [email protected] Summer: P.O. Box MXY 20, Glennallen, Alaska 99588 Winter: P.O. Box 142972, Anchorage, Alaska 99514-2972 www.wrangells.org Understanding, appreciation, and stewardship of wildlands and mountain culture in Alaska through artistic and scientific inquiry in the Wrangell Mountains Wrangell Mountains Science Bibliography April 2012 Compiled by Vanessa Skean, Barry Hecht, Sarah Davies, Nabil Kashyap and Ben Shaine We developed this bibliography for anyone interested in or seeking more scientific information about the Wrangell Mountains and the surrounding lowlands. In particular, we aimed at providing references for: Residents and visitors who seek to go further in depth than is normally possible with conventional search engines or library catalogs Scientific researchers, particularly those already familiar with generally accessible references, and those interested in finding data and insights from the grey literature not readily located on academic or vendor shelves Participants and students in WMC programs, and their colleagues in universities, schools, and agencies throughout Alaska and the world Individuals seeking to learn more about literature which pre-dates the early 1990s typical era of computerized scientific searches, commonly the early 1990s, recognizing that the Wrangells has a longer history of scientific research than most boreal areas in the western hemisphere. Students and their teachers. The bibliography has its origins in a senior project authored by Vanessa Skean while a student at Alaska Pacific University in 2009, which catalogued the holdings of the Wrangell Mountains Center library, compiled and nurtured by many WMC staff, members, and program alumni over the years.
    [Show full text]
  • GLACIERS of ALASKA by BRUCE F
    Glaciers of North America— GLACIERS OF ALASKA By BRUCE F. MOLNIA With sections on COLUMBIA AND HUBBARD TIDEWATER GLACIERS By ROBERT M. KRIMMEL THE 1986 AND 2002 TEMPORARY CLOSURES OF RUSSELL FIORD BY THE HUBBARD GLACIER By BRUCE F. MOLNIA, DENNIS C. TRABANT, ROD S. MARCH, and ROBERT M. KRIMMEL GEOSPATIAL INVENTORY AND ANALYSIS OF GLACIERS: A CASE STUDY FOR THE EASTERN ALASKA RANGE By WILLIAM F. MANLEY SATELLITE IMAGE ATLAS OF THE GLACIERS OF THE WORLD Edited by RICHARD S. WILLIAMS, Jr., and JANE G. FERRIGNO U.S. GEOLOGICAL SURVEY PROFESSIONAL PAPER 1386–K About 5 percent (about 75,000 km2) of Alaska is presently glacierized, including 11 mountain ranges, 1 large island, an island chain, and 1 archipelago. The total number of glaciers in Alaska is estimated at >100,000, including many active and former tidewater glaciers. Glaciers in every mountain range and island group are experiencing significant retreat, thinning, and (or) stagnation, especially those at lower elevations, a process that began by the middle of the 19th century. In southeastern Alaska and western Canada, 205 glaciers have a history of surging; in the same region, at least 53 present and 7 former large ice-dammed lakes have produced jökulhlaups (glacier-outburst floods). Ice-capped Alaska volcanoes also have the potential for jökulhlaups caused by subglacier volcanic and geothermal activity. Satellite remote sensing provides the only practical means of monitoring regional changes in glaciers in response to short- and long-term changes in the maritime and continental climates of Alaska. Geospatial analysis is used to define selected glaciological parameters in the eastern part of the Alaska Range.
    [Show full text]
  • Reports This Andrelated
    #NCUMC4GUQWTEG&CVC(KNG/E%CTVJ[ SWCFTCPING#NCUMC $[ 6TCXKU . *WFUQP 1RGP(KNG 4GRQTV L 6JKU TGRQTV KU RTGNKOKPCT[ CPF JCU PQV DGGP TGXKGYGF HQT EQPHQTOKV[ YKVJ 75 )GQNQIKECN 5WTXG[ GFKVQTKCN UVCPFCTFU QT YKVJ VJG 0QTVJ #OGTKECP 5VTCVKITCRJKE %QFG #P[ WUG QH VTCFG HKTO QT RTQFWEV PCOGU KU HQT FGUETKRVKXG RWTRQUGU QPN[ CPF FQGU PQV KORN[ GPFQTUGOGPV D[ VJG 75 )QXGTPOGPV 75 &'2#46/'06 1( 6*' +06'4+14 75 )'1.1)+%#. 5748'; 5GSWKO 9CUJKPIVQP McCarthy quadrangle Descriptions of the mineral occurrences shown on the accompanying figure follow. See U.S. Geological Survey (1996) for a description of the information content of each field in the records. The data presented here are maintained as part of a statewide database on mines, prospects and mineral occurrences throughout Alaska. o o o o o o o o Distribution of mineral occurrences in the McCarthy 1:250,000-scale quadrangle, Alaska This and related reports are accessible through the USGS World Wide Web site http://ardf.wr.usgs.gov. Comments or information regarding corrections or missing data, or requests for digital retrievals should be directed to: Frederic Wilson, USGS, 4200 University Dr., Anchorage, AK 99508-4667, e-mail [email protected], telephone (907) 786-7448. This compilation is authored by: Travis L. Hudson Sequim, WA Alaska Resource Data File This report is preliminary and has not been reviewed for conformity with U.S. Geologi- cal Survey editorial standards or with the North American Stratigraphic code. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S.
    [Show full text]
  • • USGS Sci8ncb for a Changing World Names Is for Descriptive Purposes Only and Does Not Imply Endorsement by the U.S
    ;.• ~. '1. " ,r-=====~=============================================== ~ u.s. Department of the Interior - U.S. Geological Survey McCarthy quadrangle Descriptions of the mineral occurrences shown on the accompanying figure follow. See U.S. Geological Survey (1996) for a description of the information content of each field in the records. The data presented here are maintained as part of a statewide database on mines, prospects and mineral occurrences throughout Alaska. I, ! •. ~ ........ \. .. ,... {~' MC~?MCO~~::·:>::·:::·~>·"fN.(~~!y,~r, ·.tJ/C034 ' ) ·.M.C032 ( .• MC::,033 . -. --, ...... ,/' ", .MC010 MC062 , MC061~ '. "\ :'-'MG['15 \, 61' '-;----111~!.&.._::::::::::::..---_l ___.::_ __...L __ .:::.::;:....::2zr::::::::......::: 61' 144' 141' Distribution of mineral occurrences in the McCarthy 1:250,OOO-scale PROPERlY Of . quadrangle, eastern Alaska 5 LIBRARY This and related reports are accessible through the USGS World Wide Web siDG6 http:j jwww-mrs-ak.wr.usgs.govjardf. Comments or information regarding corrections or missing data, or requests for digital retrievals should be directed to Donald Grybeck, USGS, 4200 University Dr., Anchorage, AK 99508-4667, e-mail [email protected], telephone (907) 786-7424. This compilation is authored by: Donald Richter U. S. Geological Survey 4200 University Drive Anchorage, AK 99508-4667 ''\ ..' ....... '-'-... ~ LocMion 01. IIlJ.p area in Al.aska This report is preliminary and has /lot been reviewed for conformity with U.S. Geological Survey editorial standards or with the North American Stratigraphic code. Any use of trade, product, or firm • USGS sci8nCB for a changing world names is for descriptive purposes only and does not imply endorsement by the U.S. Government. OPEN-FILE REPORT 98-227 ~!.,",-" ,~, , ~laska Resource Data File Pagel Site name(s): Valdez; Nugget Creek Site Type: Mine ARDF no.
    [Show full text]
  • Geochemical Data for Environmental Studies at Nabesna and Kennecott, Alaska: Water, Leachates, Stream-Sediments, Heavy-Mineral-Concentrates, and Rocks
    U.S. DEPARTMENT OF THE INTERIOR U.S. GEOLOGICAL SURVEY Geochemical Data for Environmental Studies at Nabesna and Kennecott, Alaska: Water, Leachates, Stream-Sediments, Heavy-Mineral-Concentrates, and Rocks By R.G. Eppinger, J. B. McHugh, P.H. Briggs, W.M. d'Angelo, M.W. Doughten, D.L. Fey, P.L. Hageman, R.T. Hopkins, R.J. Knight, A.L. Meier, J.M. Motooka, R.M. O'Leary, and B.H. Roushey Open-File Report 95-645A Paper version 95-645B Diskette version This report is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards and stratigraphic nomenclature. Any use of trade names is for descriptive purposes only and does not imply endorsement by the U.S. Geological Survey. U.S. Geological Survey, DFC, Box 25046, MS 973, Denver, CO, 80225 1995 CONTENTS INTRODUCTION GENERAL GEOLOGY, DEPOSIT SETTING, AND MINING HISTORY ........ 1 Nabesna ............................................. 1 Kennecott ............................................ 3 METHODS OF STUDY ....................................... 4 Sample Media ......................................... 4 Sample Collection and Preparation .............................. 8 Sediments (8); Heavy Mineral Concentrates (8); Rocks (9); Water (9); Leached Samples (9) Analytical Techniques .................................... 10 Inductively Coupled Plasma-Atomic Emission Spectrometry (10); Inductively Coupled Plasma-Mass Spectrometry (11); Ion Chromatography (12); Atomic Absorption Spectrophotometry (12); Semiquantitative Emission Spectrography (13) COMPUTERIZED DATA STORAGE ............................... 13 DESCRIPTION OF DATA TABLES ............................... 14 ACKNOWLEDGMENTS ...................................... 15 REFERENCES CITED ........................................ 16 LIST OF ILLUSTRATIONS Figure 1. Location of the Nabesna and Kennecott mines, Alaska .............. 2 Figure 2. Site locations for samples collected in the Nabesna mine area, Alaska. ..... 5 Figure 3. Detailed site locations for samples collected at the Nabesna mill, Alaska ... 6 Figure 4.
    [Show full text]
  • OFR 103 NYAC District.Indd
    ��� U.S. Department of the Interior Bureau of Land Management BLM Alaska Open File Report 103 BLM/AK/ST-06/001+3090+942 November 2005 An Investigation of the Geology and Gold Mineralization in the Nyac District, Southwest Alaska Zachary John Wenz Alaska U.S. DEPARTMENT OF THE INTERIOR BUREAU OF LAND MANAGEMMENT Mission Statement The Bureau of Land Management (BLM) sustains the health, diversity and productivity of the public lands for the use and enjoyment of present and future generations. Author Zachary John Wenz This report is the outcome of a thesis completed by the author in partial fulfillment of the requirements for a Masters of Science degree at the University of Alaska, Fairbanks. The project was supported in part by the BLM as part of the Aniak Mining District study. Cover Geologists Jeff Foley (left) and Zach Wenz examine a gold-bearing sericite-altered quartz-calcite vein zone on Bonanza Ridge, NYAC District, Southwest, Alaska (photo by Nick Enos). Open File Reports Open file reports present the results of inventories or other investigations published outside the formal BLM-Alaska technical publication series. These reports can include preliminary or incomplete data and are not published and distributed in quantity. Reports are available while supplies last from BLM External Affairs, 222 West 7th Avenue, #13, Anchorage, Alaska 99513 (907) 271-5555 and from the Juneau Minerals Information Center, 100 Savikko Road, Mayflower Island, Douglas, AK 99824, (907) 364-1553. Copies are also available for inspection at the Alaska Resource Library and Information Service (Anchorage), the United States Department of the Interior Resources Library in Washington D.C., various libraries of the University of Alaska, the BLM National Business Center Library (Denver), and other selected locations.
    [Show full text]