Program, Abstracts, and Guidebooks - University of Minnesota Duluth

More documents

Recommendations

Info

—85— THE PORT COLOWELL ALKALI COMPLEX May 9, 1970 Prepared by F. PUSKAS* *present address: The International Nickel Company of Canada Ltd., Copper Cliff, Ontario.
—87— Guide to the Port Coldwell alkalic complex INTRODUCTION: The Port Coldwell Alkali Massif (Fig. 1) is located within an Archean volcanic—sedimentary belt extending along the North shore of Lake Superior near Marathon. Previous work on the complex consists of reconnaissence work by Kerr (1910), detailed mapping by Tuominen in 1958—1959 (O.D.M. Prelim. Map P 114) and by Puskas in 1960 (O.D.M. Prelim. Map P 114, revised). The western contact of the complex wag mapped by Walker (1956); the easter-n contact by Thomson (1931) and Milne (1964). The present study was largely carried out by the writer and associates while employed by the Ontario Department of Mines. The author wishes to express his thanks to Professor Henri Loubat of Lakehead University and Clarence Kustra, Ontario Department of Mines, Resident Geologist, for their constant interest and co—operationh S. Spivak drafted the diagrams. FIELD AND GENETIC RELATIONSHIPS The Port Coldwell Alkali Massif (Fig. 1) lies within the eugeosynclinal portion of an Archean volcanosedimentary belt, approximately 18 miles wide and extending westward from White Lake, along the north shore of Lake Superior. The volcanosediments have been tightly folded in a N 70°E direction; less important, more northerly trending, structures may be attributed to cross—folding. The Archean rocks have been successively intruded by sill— like bodies of basic and ultrabasic composition, granitoids, dikes of diabasic composition, and lastly by the Port Coldwell Alkali Massif. The Alkali Massif is a lopolith (Puskas, 1964; Corbett, 1968) circular in plan and approximately 580 sq. kilometers in area. The Massif is considered to typify the so—called (Benson) Laccomorphic class of emplacements. The rocks of the massif can be divided into two groups called here the Main Group and the Secondary Group. However, in common with many intrusions of this type the long crystal— lisation history has resulted in numerous complex and sometimes confusing cross cutting relationships. The Main Group is composed of gabbros, the oldest and more-peripherally located rock—type Map unit 2), and laurvikites (Map unit 3). Both the gabbros and laurvikites can exhibit rhythmic layering which dips inward at moderate angles. The
Page 1 and 2:
-ç — — I: .t. F Geology Superi
Page 3 and 4:
TABLE OF CONTENTS INSTITUTE DIRECTO
Page 5 and 6:
-2- "P R 0 G R A M" Tate day, Ma9 5
Page 7 and 8:
-4- SESSTOM 2 1.00 Business Meeting
Page 9 and 10:
-6- F'viday, May Slit, 1970 Page No
Page 11 and 12:
-8- SYNTHESIS OF EARLY PRECAMBRIAN
Page 13 and 14:
-10- THE SOUTHERN ASSOCIATED PART O
Page 15 and 16:
-12- THE STRUCTURE OF THE NORTHERN
Page 17 and 18:
-14- MT. ST. JOSEPH - AN ARC}IAEAN
Page 19 and 20:
-16- A MODEL FOR TECTONIC VARIATION
Page 21 and 22:
-18- EARLY PRECAMBRIAN GEOLOGY OF T
Page 23 and 24:
DEFORMATION OF THE SEINE CONGLOMERA
Page 25 and 26:
-22- MINERAL POTENTIAL IN CREENSTON
Page 27 and 28:
-25-- ROOT SEVERANCE AND TECTONIC T
Page 29 and 30:
-27- STRUCTURE OF ThE DULUTH GABBRO
Page 31 and 32:
-29- 1. Department of Geology and G
Page 33 and 34:
-31-. KEWEENANWAN COPPER DEPOSITS I
Page 35 and 36:
—33- The youngest rocks in the ar
Page 37 and 38:
-35- STRUCTURAL AN!) METAMORPHIC HI
Page 39 and 40:
-37.- ARCHAEAN VOLCANIC STRATIGRAPH
Page 41 and 42: ______ __________ _____ IDEALIZED S
Page 43 and 44: —41- (3) The upper liimit of 30 p
Page 45 and 46: -43- Fjgire 2 The revised classific
Page 47 and 48: —45— EVIDENCE FOR A TROPICAL CL
Page 49 and 50: —47-- WIDESPREAD OCCURRENCE OF AL
Page 51 and 52: —49— PROTEROZOIC ROCKS IN THE T
Page 53 and 54: —51— Guide to the Proterozoic R
Page 55 and 56: WEST EAST f * . . .. . . S S S S 5S
Page 57 and 58: ________ — ;—=- — —-- —
Page 59 and 60: —53— The uppermost submember of
Page 61 and 62: —55— Morey notes that sediment
Page 63 and 64: —57— (c) layered mafic bodies,
Page 65 and 66: —59— DESCRIPTION OF STOPS Milea
Page 67 and 68: —6 P- Note downwarping of beds on
Page 69 and 70: —63— Note the lenticular chert
Page 71 and 72: —65— 0.0 From the intersection
Page 73 and 74: —67— STOP 16 In the roadcut to
Page 75 and 76: —69— ThE BEARDMORE-GERALDTON BE
Page 77 and 78: —72— the Quetico belt by Stockw
Page 79 and 80: —72 B— ABITIBI BELT —ø.jsour
Page 81 and 82: —74— Most of the metavolcanic
Page 83 and 84: —76— SELECTED REFERENCES Anonym
Page 85 and 86: —78— Stockwell, C. II., 1964; F
Page 87 and 88: —80— ae DESCRIPTION OF STOPS 0.
Page 89 and 90: —82— STOP 8 (Paint Lake Fault).
Page 91: -84— Outcrops near the road are o
Page 95 and 96: AGE RELATIONSHIPS The volcanosedime
Page 97 and 98: .• ____________________ . — .._
Page 99 and 100: -I- + -4.- -I- - - - - — - 4- ; E
Page 101 and 102: —93— (3) 'flow—layering' exhi
Page 103 and 104: GOSSAN ZONE IN SULPHIDE BEARING GAB
Page 105 and 106: —95— (3) feldspars variably fol
Page 107 and 108: —97— Fig. 6c Fig. 6b ;' TRAIL T
Page 109 and 110: Pig. 7 West contact of CROSS SECTIO
Page 111: PRINCE AR THUR HOTEL ® 0 ® SHOREL
show all

Program, Abstracts, and Guidebooks - University of Minnesota Duluth

Create successful ePaper yourself

Delete template?

Save as template?