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Shorter Contributions to C*L Y • Shorter Contributions to C*L y • GEOLOGICAL Shorter Contributions to Mineralogy and Petrology, 1979 The Vermilion Granitic Complex—A New Name for Old Rocks in Northern Minnesota By D. L. SOUTHWICK and P. K. SIMS Potassium-Argon Ages from the Mount Taylor Volcanic Field, New Mexico By PETER W. LIPMAN and HARALD H. MEHNERT Crystals of Coexisting Alunite and Jarosite, Goldfield, Nevada By WILLIAM J. KEITH, LEWIS CALK, and R. P. ASHLEY Zeolitization of Tertiary Tuffs in Lacustrine and Alluvial Deposits in the Ray- San Manuel Area, Pinal and Gila Counties, Arizona By MEDORA H. KRIEGER Drake Peak-A Structurally Complex Rhyolite Center in Southeastern Oregon By RAY E. WELLS Palladium, Platinum, and Rhodium Concentrations in Mafic and Ultramafic Rocks from the Zhob Valley and Dargai Complexes, Pakistan By NORMAN J. PAGE, JOSEPH HAFFTY, and ZAKI AHMAD GEOLOGICAL SURVEY PROFESSIONAL PAPER 1124-A-F UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON: 1980 UNITED STATES DEPARTMENT OF THE INTERIOR CECIL D. ANDRUS, Secretary GEOLOGICAL SURVEY H. William Meiiard, Director Library of Congress catalog-card No. 79-600186 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 Stock Number 024-001-03247-3 CONTENTS [Letters designate the chapters] (A) The Vermilion Granitic Complex—A New Name for Old Rocks in Northern Minnesota, by D. L. Southwick and P. K. Sims (B) Potassium-Argon Ages from the Mount Taylor Volcanic Field, New Mexico, by Peter W. Lipman and Harald H. Mehnert (C) Crystals of Coexisting Alunite and Jarosite, Goldfield, Nevada, by William J. Keith, Lewis Calk, and R. P. Ashley (D) Zeolitization of Tertiary Tuffs in Lacustrine and Alluvial Deposits in the Ray-San Manuel Area, Final and Gila Counties, Arizona, by Medora H. Krieger (E) Drake Peak-A Structurally Complex Rhyolite Center in Southeastern Oregon, by Ray E. Wells (F) Palladium, Platinum, and Rhodium Concentrations in Mafic and Ultramafic Rocks from the Zhob Valley and Dargai Complexes, Pakistan, by Norman J. Page, Joseph Haffty, and Zaki Ahmad CONVERSION FACTORS Metric unit Inch-Pound equivalent Metric unit Inch-Pound equivalent Length Specific combinations— Continued millimeter (mm) = 0.03937 inch (in) liter per second (L/s) = .0353 cubic foot per second meter (m) = 3.28 feet (ft) cubic meter per second = 91.47 cubic feet per second per kilometer (km) = .62 mile (mi) per square kilometer square mile [(ft3/s)/mi2] [(mVs)/km2] meter per day (m/d) = 3.28 feet per day (hydraulic Area conductivity) (ft/d) square meter (m2) = 10.76 square feet (ft2) meter per kilometer = 5.28 feet per mile (ft/mi) square kilometer (km2 ) = .386 square mile (mi2 ) (m/km) hectare (ha) = 2.47 acres kilometer per hour — .9113 foot per second (ft/s) Volume (km/h) meter per second (m/s) — 3.28 feet per second cubic centimeter (cm3 ) = 0.061 cubic inch (in3) meter squared per day = 10.764 feet squared per day (ft2/d) liter (L) = 611.03 cubic inches (m2/d) (transmissivity) cubic meter (m3) = 35.31 cubic feet (ft») cubic meter per second = 22.826 million gallons per day cubic meter = .00081 acre-foot (acre-ft) (m.3/s) (Mgal/d) cubic hectometer (hm3) = 810.7 acre-feet liter = 2.113 pints (pt) cubic meter per minute = 264.2 gallons per minute (gal/min) liter = 1.06 quarts (qt) (m3/min) liter = .26 gallon (gal) liter per second (L/s) = 15.85 gallons per minute cubic meter = .00026 million gallons (Mgal or liter per second per = 4.83 gallons per minute per foot 109 gal) meter [(L/s)/m] [(gal/min) /ft] cubic meter = 6.290 barrels (bbl) (1 bbl = 42 gal) kilometer per hour — .62 mile per hour (mi/h) Weight (km/h) meter per second (m/s) — 2.237 miles per hour gram (g) = 0.035 ounce, avoirdupois (oz avdp) gram per cubic = 62.43 pounds per cubic foot (Ib/ft3) gram ;= .0022 pound, avoirdupois (Ib avdp) centimeter (g/crn3 ) metric tons (t) = 1.102 tons, short (2,000 Ib) gram per square = 2.048 pounds per square foot (lb/ft2) metric tons = 0.9842 ton, long (2,240 Ib) centimeter (g/cm2 ) gram per square = .0142 pound per square inch (lb/in2) Specific combinations centimeter kilogram per square _ 0.96 atmosphere (atm) centimeter (kg/ cm2 ) Temperature kilogram per square — .98 bar (0.9869 atm) centimeter degree Celsius (°C) = 1.8 degrees Fahrenheit (°F) cubic meter per second = 35.3 cubic feet per second (ft3/s) degrees Celsius = [(1.8X°C)+32] degrees Fahrenheit (m3/s) (temperature) The Vermilion Granitic Complex A New Name for Old Rocks in Northern Minnesota By D. L. SOUTHWICK and P. K. SIMS SHORTER CONTRIBUTIONS TO MINERALOGY AND PETROLOGY, 1979 GEOLOGICAL SURVEY PROFESSIONAL PAPER 1 1 2 4 - A Prepared with the cooperation of the Minnesota Geological Survey CONTENTS Page Abstract _______________________________________ — ____-- A! Introduction ______________________________________________________________ 1 Subdivisions of the Vermilion Granitic Complex ______________-___-_----_— 4 Note on the terminology of migmatites _______________ — _______________ 5 Lac La Croix Granite ___________________________ — ______ — _______ 5 Granite-rich migmatite related to the Lac La Croix Granite _____ — _______ 6 Schist-rich migmatite related to the Lac La Croix Granite _____ — __ — _____ 7 Amphibolite and amphibolite migmatite _______________ — ______ — — _____ 7 Intrusive rocks that are geologically older than the Lac La Croix Granite __ 8 Migmatite geologically older than the gray granodiorite __________________ 8 Burntside Gneiss _________________________________________________ 8 Biotite schist _____________________________________________________ 9 Pegmatite _________________________________________________ — _____— 9 Age of the complex _________________________________ ——— _——— 10 References cited __________________________________________________ 10 ILLUSTRATIONS Page FIGURE 1. Generalized geologic map, showing the Vermilion Granitic Complex ________________________________ A2 2. Schematic diagram of the interrelationships among the lithologic subdivisions of the Vermilion Granitic Complex __________________________________________________________________________________ 4 TABLES Page TABLE 1. Average modal composition of the Lac La Croix Granite and neosome of granite-rich migmatite _________ A6 2. Chemical analyses of the Lac La Croix Granite (includes neosome of granite-rich migmatite) _______ 6 3. Average modal composition of gray granodiorite, tonalite, and trondhjemite _______________ 8 4. Chemical analyses of gray granodiorite and trondhjemite, including the Burntside Gneiss ____________ 9 in SHORTER CONTRIBUTIONS TO MINERALOGY AND PETROLOGY, 1979 THE VERMILION GRANITIC COMPLEX— A NEW NAME FOR OLD ROCKS IN NORTHERN MINNESOTA By D. L. SouTHWiCK1 and P. K. SIMS ABSTRACT Granite as defined by Grout 1923) ; it includes some The name Vermilion Granitic Complex is introduced for rocks previously included in the abandoned terms the heterogeneous granitic and migmatitic rocks of Archean "Vermilion series, Vermilion schist, and Vermilion (formerly called Precambrian W) age that occur north of the Vermilion district and south of the Kabetogama peninsula in group," as used by Winchell and Winchell (1887, northern Minnesota. The complex consists of the following p. 4, 192, 355, 357) and Van Hise and Clements subdivisions: Lac La Croix Granite, granite-rich migmatite, (1901). schist-rich migmatite, quartz-feldspar gneiss, hornblende The greater part of the Vermilion Granitic Com­ quartz diorite and diorite, granodiorite and trondhjemite, amphibolite and amphibolite migmatite, older migmatite, bio- plex consists of pink to grayish-pink biotite granite tite schist, Burntside Gneiss, and pegmatite. Because the (as classified by Streckeisen (1973) and as used by name Vermilion Granitic Complex is proposed as a more Minnesota geologists for decades), and genetically inclusive group term, the more restricted name Vermilion associated granite-rich migmatite. These rocks con­ Granite (Grout, 1923) is hereby abandoned. The new name stitute the Vermilion Granite of Grout (1923). Lac La Croix Granite is proposed for the uniform, light-pink biotite granite that occurs widely in the eastern and central Within the area dominated by granite, lesser vol­ parts of the complex. It is denned as having less than 5 per­ umes of other igneous and metamorphic rocks are cent of schistose or gneissic inclusions and is therefore more intimately involved with the granite; moreover, on restricted than the Vermilion Granite of Grout (1926), which the north and west the granitic terrane passes gra- included sustantial amounts of migmatitic rocks. The name dationally through migmatites rich in schist into Burntside Gneiss is adopted as a replacement for the older term Burntside Granite Gneiss, originally named by Grout nonmigmatized biotite schist. We view the minor (1926). This change is required by the conclusion that the lithologies within and the migmatite around the rock is a metamorphosed dacite and not a metamorphosed granitic terrane to be logically parts of a larger rock granite, as formerly interpreted. body. Accordingly, we recommend the Vermilion Granite as used by Grout (1923) be elevated in rank INTRODUCTION and broadened to the Vermilion Granitic Complex, The name Vermilion Granitic Complex is pro­ as described below. The complex is named for the posed for the heterogeneous granitic and migmatitic Vermilion River, along which most of its lithologic rocks of Archean (formerly called Precambrian W) subdivisions are exposed. age that occur niorth of the Vermilion district and The northern boundary
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