DOCSLIB.ORG

Preliminary Results of Bedrock Mapping at Bigstone Lake, Northwestern Superior Province, Manitoba (Parts of NTS 53E12, 13) by M.L

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Preliminary Results of Bedrock Mapping at Bigstone Lake, Northwestern Superior Province, Manitoba (Parts of NTS 53E12, 13) by M.L GS-5 Preliminary results of bedrock mapping at Bigstone Lake, northwestern Superior province, Manitoba (parts of NTS 53E12, 13) by M.L. Rinne, S.D. Anderson and K.D. Reid Rinne, M.L., Anderson, S.D. and Reid, K.D. 2016: Preliminary results of bedrock mapping at Bigstone Lake, northwest- ern Superior province, Manitoba (parts of NTS 53E12, 13); in Report of Activities 2016, Manitoba Growth, Enterprise and Trade, Manitoba Geological Survey, p. 51–62. Summary groups, including their con- The Manitoba Geological Survey (MGS) began tained mineral occurrences; 1:20 000 scale mapping of the Bigstone Lake area in the and summer of 2016 as part of a renewed study of supracrustal • provide a revised assessment of mineral potential in rocks in the Bigstone–Wass–Knight lakes area. Results this part of the Superior province. of this field season, building partly on previous work, The Bigstone Lake area has been subject to sporadic included: 1) delineation of several ultramafic cumulates precious- and base-metal exploration activity since 1920, and related flows in the lower part of the greenstone belt including airborne and ground-loop electromagnetic sur- stratigraphy, with potential for Ni-sulphide mineraliza- veys, and has been tested by a total of 91 drillholes col- tion; 2) recognition of shallowing water depth during lared mostly along the southeastern shoreline. The largest emplacement of the volcanic stratigraphy, with potential exploration campaign was conducted by Noranda Explo- for precious-metal–rich volcanogenic massive sulphide ration Co. Ltd., from 1982 to 1986; the last submitted (VMS) deposits in the uppermost portions of the volcanic assessment report for this work recommended continued stratigraphy; 3) possible evidence of a major unconfor- drill testing of Zn and Au mineralization (Assessment File mity between rocks of the Hayes River and Island Lake 94359). Since 1986, no work has taken place at Bigstone groups; 4) definition of several regional alteration zones, Lake, apart from brief visits to a few outcrops as part of including mineral assemblages known elsewhere to occur a regional geochemical sampling program undertaken in in association with base-metal and/or shear-hosted gold deposits; and 5) recognition of a complex structural his- tory, including regional isoclinal and open folding fol- lowed by episodes of late shearing, with implications for understanding potential controls on vein-hosted precious- metal mineralization in the region. Introduction The Bigstone Lake area in east-central Manitoba (Figure GS-5-1) contains a wide range of Archean supra- crustal rock types, including ultramafic, mafic and felsic volcanic packages (Neale et al., 1986; Herd et al., 1987), and is considered to have potential for several types of mineral deposit. It includes a documented gold occur- rence, with reported values up to 72.3 g/t Au (Assessment File 94359, Manitoba Growth, Enterprise and Trade, Winnipeg), along with features potentially related to the formation of VMS deposits (e.g., zones of sphalerite and chalcopyrite mineralization, sodium depletion and chlo- rite alteration; Assessment File 94359). This document summarizes the results of field work Figure GS-5-1: Simplified geological domains of the undertaken in 2016 at Bigstone Lake. The work is part of northwestern Superior province, showing the locations of a project intended to selected greenstone belts (labelled) and the 2016 map- • document the supracrustal rocks of the Bigstone, ping area (outlined). Domain names are in italics and are Wass and Knight lakes area through systematic labelled as shown in Pilkington and Thomas (2001). Min- eral occurrences shown are mostly Au, Cu, Ni, Ag or Zn; shoreline mapping, supplemented by geochemical occurrences shown in the Island Lake greenstone belt and geochronological analyses; include two known gold deposits. Abbreviations: BLGB, • investigate regional stratigraphic and structural rela- Bigstone Lake greenstone belt; KWGB, Knight and Wass tionships between the Hayes River and Island Lake lakes greenstone belt; ILGB, Island Lake greenstone belt. Report of Activities 2016 51 1999 by Hudson Bay Exploration and Development Co. Local geology Ltd. (Assessment File 73614). Units documented during the 2016 field season are Geological mapping at Bigstone Lake was carried described here from oldest to youngest interpreted age. All of the rocks have been metamorphosed to upper- out in 1939 by MGS geologist R. McIntosh at 1:63 360 greenschist to lower-amphibolite facies; in the interest of scale (McIntosh, 1941), in 1974–1975 by geologists brevity, the ‘meta’ prefix is not used in this report. of the Geological Survey of Canada at 1:63 360 scale (Ermanovics, 1975; Ermanovics et al., 1975; Herd and Ermanovics, 1976) and in 1984–1985 by MGS geologist Lower stratigraphic sequence (Hayes River group) K. Neale at 1:20 000 scale (Neale, 1984, 1985; Neale et The oldest and lowermost supracrustal units of the al., 1986). Mapping by Neale (1984–1985) was mostly BLGB define the outer limbs of a belt-scale syncline limited to the eastern third of the 2016 mapping area. (Figure GS-5-2). The sequence consists mostly of mafic Detailed mapping at 1:10 000 scale was also undertaken to ultramafic intrusions and flows, with subordinate felsic in 1985 by Noranda geologists over a small portion of volcanic units and interflow sedimentary packages. the southeastern shoreline. The results of these mapping programs were used to inform the geological boundaries Lower mafic volcanic flows outside of the mapping area shown in Figure GS-5-2a, Basalt of the lower sequence is the most abundant particularly in areas inland. rock type in the BLGB, occurring along the outer belt Seven weeks of shoreline mapping at 1:20 000 scale margins in flow packages up to 5 km in apparent thickness was carried out during the summer at Bigstone Lake. A (Figure GS-5-2a). Variolitic pillowed flows make up two total of 670 stations were described, with 119 samples thirds of the unit and are typically grey-green on fresh and collected for geochemical, petrographic or geochronolog- weathered surfaces, aphyric and highly strained. On aver- ical analyses. Despite high water levels, excellent expo- age, pillows 20–80 cm thick are elongated (~4:1 aspect sures were encountered at several locations, mostly along ratios) along the regional S3 fabric, with significant local the central island chains. Inland access was particularly variations (up to 15:1) reflecting strain partitioning. Pil- difficult in the recently burned area along the southeastern low selvages 0.5–3 cm thick are generally well-preserved shore of Bigstone Lake (near the sphalerite occurrence and varioles 0.2–2 cm across, which coalesce toward pil- labeled in Figure GS-5-2b) and in densely forested areas low centres, make up between 50 and 80% of most out- around the southwestern tip of Bigstone Lake. crops. Massive, sparsely plagioclase-phyric basalt makes up the remaining third of the lower sequence mafic flows. Where least strained, the massive basalt contains ~20% Regional geology plagioclase phenocrysts <0.5 mm long and appears to transition into the gabbro unit described below. The Bigstone Lake greenstone belt (BLGB) is located in the northwestern Superior province, approxi- Concentric pillow fractures, finely bedded interpil- mately 70 km west of the Island Lake greenstone belt, low hyaloclastite, coarse interflow hyaloclastite-breccia layers, quartz-filled pillow shelves and rare quartz-filled and is contiguous with supracrustal rocks at Knight and amygdules up to 2 cm across were also documented in Wass lakes (Figure GS-5-1). Archean supracrustal rocks the flows. Shelves, amygdules and well-developed cusps of the Bigstone, Knight, Wass and Island lakes areas consistently indicate younging toward the belt centre (as share a generalized stratigraphy consisting of rocks of summarized in Figure GS-5-2b). the Hayes River group overlain by rocks of the Island Lake group. The Hayes River group is an arc-derived Subordinate components of the lower mafic flow sequence of mafic and minor ultramafic flows and unit, which are too small to display as separate units, intrusions transitioning to felsic flows and pyroclastic include interflow oxide-facies iron formation in layers rocks, which were (in the Island Lake region) emplaced <50 cm thick, mafic crystal-rich tuff (locally containing between ca. 2900 and 2861 Ma (Stevenson and Turek, zoned plagioclase up to 1 cm across) in rare beds up to a 1992). The Island Lake group is a sedimentary (±vol- few metres thick and rhyolite dikes <3 m thick. The rhyo- lite dikes are most abundant along the southeastern limb canic) sequence of basal conglomerate and marine of the BLGB, and are interpreted to be cogenetic with the turbidites, which were deposited ca. 2749–2729 Ma felsic volcanic and volcaniclastic units described below. (Neale, 1985; Herd et al., 1987; Stevenson and Turek, 1992). Late (post-Hayes River group) volcanic units are included in the Island Lake group described by Herd Felsic volcanic and volcaniclastic units et al. (1987), whereas Neale (1985) assigned them to a Felsic igneous rocks are intercalated with the lower (possibly unrelated) late supracrustal group. The supra- mafic volcanic flows in the eastern half of the BLGB, crustal units were intruded by granitoid plutons ranging both north and south of Bigstone Lake (Figure GS-5-2a). in age from ca. 2729 to 2699 Ma (Turek et al., 1986). Rhyolite to rhyodacite flows or domes make up about 52 Manitoba Geological
Load more

Recommended publications
  • 20000018459: 2019 Diamond Drilling Campaign Report, Sturgeon Lake
    We are committed to providing accessible customer service. If you need accessible formats or communications supports, please contact us. Nous tenons à améliorer l’accessibilité des services à la clientèle. Si vous avez besoin de formats accessibles ou d’aide à la communication, veuillez nous contacter. 1 GLENCORE CANADA CORPORATION 2019 DIAMOND DRILLING CAMPAIGN REPORT STURGEON LAKE PROPERTY ONTARIO, CANADA Report completed on May 1st, 2020 Pascal Lessard, P.Geo. Guillaume Ratthe, M. Sc., P.Geo. TABLE OF CONTENTS LIST OF ILLUSTRATIONS .......................................................................................................... iii LIST OF TABLES .......................................................................................................................... iv APPENDICES ................................................................................................................................ iv SUMMARY .................................................................................................................................... 5 1.0. Introduction .......................................................................................................................... 6 2.0. Localisation .......................................................................................................................... 6 3.0. History of the property ....................................................................................................... 11 4.0. Regional geology ..............................................................................................................
    [Show full text]
  • Lithostratigraphic Assembly of the Eastern Rice Lake Greenstone Belt and Structural Setting of Gold Mineralization at Bissett, Manitoba
    Electronic Capture, 2008 The PDF file from which this document was printed was generated by scanning an original copy of the publication. Because the capture method used was 'Searchable Image (Exact)', it was not possible to proofread the resulting file to remove errors resulting from the capture process. Users should therefore verify critical information in an original copy of the publication. © 1996: This book, or portions of it, may not be reproduced in any form without written permission ofthe Geological Association of Canada, Winnipeg Section. Additional copies can be purchased from the Geological Association of Canada, Winnipeg Section. Details are given on the back cover. TABLE OF CONTENTS ABSTRACT.............. 1 INTRODUCTION.......................................................................................................... 1 REGIONAL GEOLOGY.. 3 REGIONAL GEOPHySiCS........................................................................................... 5 LOCAL GEOLOGy....................................................................................................... 7 Bissett Area 7 Long Lake- Stormy Lake Area 10 Gem Lake Area 12 Garner Lake Area 12 Wallace Lake area 14 Wanipigow Lake - Little Beaver Lake Area 16 STRUCTURE 18 LITHOGEOCHEMIS·rRy...................................................................................................... 25 GEOCHRONOLOGy 25 TECTONIC INTERPRETATION 27 ECONOMIC GEOLOGy 31 FIELD TRIP STOPS 34 DAY 1: The Long Lake - Stormy Lake - Manigotagan River Area 36 DAY 2 - The Garner Lake-Wallace Lake-Wanipigow River Area 58 DAY 3 - The Bissett Area 74 MINING HiSTORy 89 Manigotagan Area 89 Bissett Area 89 Long Lake - Stormy Lake Area....................... 94 Gem Lake Area 95 Wallace Lake Area 96 Wanipigow Lake - Little Beaver Lake Area 97 REFERENCES 99 LITHOSTRATIGRAPHIC ASSEMBLY AND STRUCTURAL SETTING OF GOLD MINERALIZATION IN THE EASTERN RICE LAKE GREENSTONE BELT K.H. Poulsen (GSC), W. Weber (Man. Energy and Mines), R. Brommecker (WMC International) and D.N.Seneshen (Queen's University).
    [Show full text]
  • The Rouyn-Pelletier Caldera Complex of the Blake River Group, Abitibi Greenstone Belt, Canada
    Canadian Journal of Earth Sciences Reconstruction and evolution of Archean intracaldera facies: the Rouyn-Pelletier Caldera Complex of the Blake River Group, Abitibi greenstone belt, Canada Journal: Canadian Journal of Earth Sciences Manuscript ID cjes-2015-0029.R2 Manuscript Type: Article Date Submitted by the Author: 03-Jan-2016 Complete List of Authors: Moore, Lyndsay N.; Université du Québec à Chicoutimi, Dépt. Sciences de la Terre Draft Daigneault, Réal; Université du Québec à Chicoutimi, Dépt. Sciences de la Terre Aird, Hannah M.; California State University Chico, Geological and Environmental Sciences Department Banerjee, Neil R.; Western University, Department of Earth Sciences Mueller, Wulf U.; Module des Sciences de la Terre Keyword: Archean, subaqueous, caldera, volcanic architecture, facies https://mc06.manuscriptcentral.com/cjes-pubs Page 1 of 70 Canadian Journal of Earth Sciences Reconstruction and evolution of Archean intracaldera facies: the Rouyn-Pelletier Caldera Complex of the Blake River Group, Abitibi greenstone belt, Canada Moore, L.N. a, Daigneault, R. a, Aird, H.M. b, Banerjee, N.R. c and Mueller, W.U. a,1 a Centre d’études sur les ressources minérales (CERM), Université du Québec à Chicoutimi (UQAC) 555 boul. de l’Université, Chicoutimi, Québec, Canada, G7H 2B1 b Geological and Environmental Sciences Department (GEOS), California State University - Chico, Chico, California, 95929 c Department of Earth Sciences, Western University, London, Ontario, N6A 5B7 1 Deceased on May 16 th , 2010 Draft Corresponding Author: [email protected] Telephone: 1-418-545-5011 Fax: 1-418-545-5012 Present Address: Université du Québec à Chicoutimi, 555 boul. de l’Université, Chicoutimi, Québec, Canada, G7H 2B1 https://mc06.manuscriptcentral.com/cjes-pubs Canadian Journal of Earth Sciences Page 2 of 70 1 Abstract 2 Sub-vertically- to vertically-dipping Archean strata provide an excellent opportunity to study 3 synvolcanic structures and internal organization of subaqueous volcanic complexes.
    [Show full text]
  • Shallow Three-Dimensional Structure from Two-Dimensional Crooked Line Seismic Reflection Data Over the Sturgeon Lake Volcanic Complex
    Economic Geology Vol. 97, 2002, pp. 1779–1794 Shallow Three-Dimensional Structure from Two-Dimensional Crooked Line Seismic Reflection Data over the Sturgeon Lake Volcanic Complex MLADEN R. NEDIMOVIC´†,* AND GORDON F. W EST Geophysics Laboratories, Department of Physics, University of Toronto, 60 St. George St., Toronto, Ontario M5S 1A7, Canada Abstract In principle, partial three-dimensional structural information can be obtained from two-dimensional crooked line seismic reflection data by processing the traces as swath three-dimensional data, but this poten- tial has rarely, if ever, been fully exploited. Here, we apply procedures newly designed for this purpose to min- ing exploration data from a high-resolution, two-dimensional crooked line survey over a part of the Sturgeon Lake Archean greenstone belt in northwest Ontario, Canada. We then examine the results in the light of geo- logic data based on about 20 years of mining activity in the immediate area. The area appears highly reflective, even when using standard two-dimensional data-processing methods. But because geologic dips in the section are typically steep and the majority of viewable contact surfaces do not lie directly below the processing and acquisition lines, special data-processing procedures have been essential. Despite appreciable background noise in the constructed images owing to the limitations of the crooked line data set, a large variety of reflection events are quite clearly positioned in three dimensions. The acquisition and processing lines run northeast-southwest, and most of the observed reflection events strike approximately east-west and dip northward. In the upper 1.5 km, they correlate well with expected layering of the mafic-felsic volcanic rocks, and in the vicinity of the Cu-Zn volcanogenic massive sulfide deposit at Lyon Lake, they agree well with information from drilling.
    [Show full text]
  • Preliminary Compilation of Descriptive Geoenvironmental Mineral Deposit Models
    U.S. DEPARTMENT OF THE INTERIOR U.S. GEOLOGICAL SURVEY Preliminary compilation of descriptive geoenvironmental mineral deposit models Edward A. du Bray1 , Editor Open-File Report 95-831 This report is preliminary and has not 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 names is for descriptive purposes only and does not imply endorsement by the U.S. Government. 'Denver, Colorado 1995 CONTENTS Geoenvironmental models of mineral deposits-fundamentals and applications, by G.S. Plumlee and J.T. Nash ................................................. 1 Bioavailability of metals, by D.A. John and J.S. Leventhal ................................... 10 Geophysical methods in exploration and mineral environmental investigations, by D.B. Hoover, D.P. Klein, and D.C. Campbell ............................................... 19 Magmatic sulfide deposits, by M.P. Foose, M.L. Zientek, and D.P. Klein ......................... 28 Serpentine- and carbonate-hosted asbestos deposits, by C.T. Wrucke. ............................ 39 Carbonatite deposits, by P.J. Modreski, T.J. Armbrustmacher, and D.B. Hoover .................... 47 Th-rare earth element vein deposits, by T.J. Armbrustmacher, P.J. Modreski, D.B. Hoover, and D.P. Klein ........................................................... 50 Sn and (or) W skarn and replacement deposits, by J.M. Hammarstrom, J.E. Elliott, B.B. Kotlyar, T.G. Theodore, J.T. Nash, D.A. John, D.B. Hoover, and D.H. Knepper, Jr. ................. 54 Vein and greisen Sn and W deposits, by J.E. Elliott, R.J. Kamilli, W.R. Miller, and K.E. Livo ......... 62 Climax Mo deposits, by S. Ludington, A.A. Bookstrom, R.J. Kamilli, B.M.
    [Show full text]
  • Regional Geology, Sioux Lookout Orogenic Belt
    Ontario Geological Survey Open File Report 6017 Regional Geology of the Sioux Lookout Orogenic Belt, Western Wabigoon Subprovince: Stages of Archean Volcanism, Sedimentation, Tectonism and Mineralization 2000 ONTARIO GEOLOGICAL SURVEY Open File Report 6017 Regional Geology of the Sioux Lookout Orogenic Belt, Western Wabigoon Subprovince: Stages of Archean Volcanism, Sedimentation, Tectonism and Mineralization by J.R. Devaney 2000 Parts of this publication may be quoted if credit is given. It is recommended that reference to this publication be made in the following form: Devaney, J.R. 2000. Regional geology of the Sioux Lookout orogenic belt, western Wabigoon Subprovince: stages of Archean volcanism, sedimentation, tectonism and mineralization; Ontario Geological Survey, Open File Report 6017, 151p. e Queen’s Printer for Ontario, 2000 e Queen’s Printer for Ontario, 2000. Open File Reports of the Ontario Geological Survey are available for viewing at the Mines Library in Sudbury, at the Mines and Minerals Information Centre in Toronto, and at the regional Mines and Minerals office whose district includes the area covered by the report (see below). Copies can be purchased at Publication Sales and the office whose district includes the area covered by the report. Al- though a particular report may not be in stock at locations other than the Publication Sales office in Sudbury, they can generally be obtained within 3 working days. All telephone, fax, mail and e-mail orders should be directed to the Publica- tion Sales office in Sudbury. Use of VISA or MasterCard ensures the fastest possible service. Cheques or money orders should be made payable to the Minister of Finance.
    [Show full text]
  • Min Allen Et Al Quenching of
    ÔØ ÅÒÙ×Ö ÔØ Quenching of steam-charged pumice: Implications for submarine pyroclastic volcanism S.R. Allen, R.S. Fiske, K.V. Cashman PII: S0012-821X(08)00421-4 DOI: doi: 10.1016/j.epsl.2008.06.050 Reference: EPSL 9389 To appear in: Earth and Planetary Science Letters Received date: 19 February 2008 Revised date: 23 June 2008 Accepted date: 29 June 2008 Please cite this article as: S.R. Allen, R.S. Fiske, K.V. Cashman, Quenching of steam- charged pumice: Implications for submarine pyroclastic volcanism, Earth and Planetary Science Letters (2008), doi: 10.1016/j.epsl.2008.06.050 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. ACCEPTED MANUSCRIPT 1 Quenching of steam-charged pumice: Implications for submarine pyroclastic 2 volcanism 3 4 S.R. Allena,*, R.S. Fiskeb, K.V. Cashmanc 5 6 aSchool of Earth Sciences and Centre of Excellence in Ore Deposits, University of 7 Tasmania, Private Bag 79, Hobart, Tasmania 7001, Australia, [email protected] 8 9 bSmithsonian Institution MRC-119, Washington, DC 20560, USA, [email protected] 10 11 cDepartment of Geological Sciences, University of Oregon, Eugene, OR 97403-1272, 12 USA, [email protected] 13 14 * Corresponding author: Tel.: +61 3 62267635; fax: +61 3 6226 7662.
    [Show full text]
  • Physical Volcanology, Hydrothermal Alteration and Massive Sulphide Deposits of the Sturgeon Lake Caldera R
    Electronic Capture, 2008 The PDF file from which this document was printed was generated by scanning an original copy of the publication. Because the capture method used was 'Searchable Image (Exact)', it was not possible to proofread the resulting file to remove errors resulting from the capture process. Users should therefore verify critical information in an original copy of the publication. © 1996: This book, or portions of it, may not be reproduced in any form without written permission ofthe Geological Association of Canada, Winnipeg Section. Additional copies can be purchased from the Geological Association of Canada, Winnipeg Section. Details are given on the back cover. TABLE OF CONTENTS INTRODUCTION 1 REGIONAL GEOLOGY 3 PHYSICAL VOLCANOLOGY OF THE STURGEON LAKE CALDERA COMPLEX 7 Precaldera Volcanics 7 Jackpot Lake Succession 7 High Level Lake Succession 8 Tailings Lake Succession 9 Mattabi Succession 10 L Succession 12 SUMMARY OF THE VOLCANOLOGICAL HISTORY OF THE STURGEON LAKE CALDERA COMPLEX 13 HYDROTHERMAL ALTERATION 17 FIELD TRIP STOP DESCRIPTIONS 22 F-Group Area 24 Mattabi - Area "16" 26 Area 17 32 REFERENCES 35 LIST OF TABLES AND FIGURES Tables Table I. Grade and tonnage figures of ore deposits in the south Sturgeon Lake area. 1 Figures Figure 1. Location of the south Sturgeon Lake area. 2 Figure 2. Generalized geological map illustrating the regional extent of the Sturgeon Lake Caldera Complex. 3 Figure 3. Simplified geological map of the Sturgeon Lake Caldera Complex. 6 Figure 4. Stratigraphic correlations between the F-Group and Mattabi areas. 16 Figure 5. Distribution of ore-forming alteration assemblages associated with the F-Group area.
    [Show full text]
  • Quartz-Kyanite Pods in the Tusas Mountains, Northern New Mexico: a Sheared and Metamorphosed Fossil Hydrothermal System in the Vadito Group Metarhyolite Mary C
    New Mexico Geological Society Downloaded from: http://nmgs.nmt.edu/publications/guidebooks/62 Quartz-kyanite pods in the Tusas Mountains, northern New Mexico: A sheared and metamorphosed fossil hydrothermal system in the Vadito Group metarhyolite Mary C. Simmons, Karl E. Karlstrom, Michael W. Williams, and Toti E. Larson, 2011, pp. 359-378 in: Geology of the Tusas Mountains and Ojo Caliente, Author Koning, Daniel J.; Karlstrom, Karl E.; Kelley, Shari A.; Lueth, Virgil W.; Aby, Scott B., New Mexico Geological Society 62nd Annual Fall Field Conference Guidebook, 418 p. This is one of many related papers that were included in the 2011 NMGS Fall Field Conference Guidebook. Annual NMGS Fall Field Conference Guidebooks Every fall since 1950, the New Mexico Geological Society (NMGS) has held an annual Fall Field Conference that explores some region of New Mexico (or surrounding states). Always well attended, these conferences provide a guidebook to participants. Besides detailed road logs, the guidebooks contain many well written, edited, and peer-reviewed geoscience papers. These books have set the national standard for geologic guidebooks and are an essential geologic reference for anyone working in or around New Mexico. Free Downloads NMGS has decided to make peer-reviewed papers from our Fall Field Conference guidebooks available for free download. Non-members will have access to guidebook papers two years after publication. Members have access to all papers. This is in keeping with our mission of promoting interest, research, and cooperation regarding geology in New Mexico. However, guidebook sales represent a significant proportion of our operating budget. Therefore, only research papers are available for download.
    [Show full text]
  • The Blake River Group, Abitibi Greenstone Belt
    Precambrian Research 168 (2009) 66–82 Contents lists available at ScienceDirect Precambrian Research journal homepage: www.elsevier.com/locate/precamres An Archean megacaldera complex: The Blake River Group, Abitibi greenstone belt V. Pearson a, R. Daigneault b,∗ a CONSOREM – Consortium de recherche en exploration minérale, 555 Boul. de l’Université, Chicoutimi, Canada G7H 2B1 b Centre d’études sur les Ressources minérales (CERM) – Université du Québec à Chicoutimi, 555 Boul. de l’Université, Chicoutimi, Canada G7H 2B1 article info abstract Article history: The Archean Blake River Group of the southern Abitibi greenstone belt is defined as a subaqueous mega- Received 3 July 2007 caldera. Compelling evidence include: (1) a radial and concentric organization of synvolcanic mafic to Received in revised form 31 March 2008 intermediate dykes, (2) an overall dome geometry defined by the volcanic strata, (3) a peripheral dis- Accepted 31 March 2008 tribution of subaqueous volcaniclastic units, (4) a zonal distribution of carbonate alteration, and (5) a distinct annular synvolcanic inner and outer ring fault pattern. Three caldera-forming events have been Keywords: identified: (1) the early Misema caldera, (2) the New Senator caldera, and (3) the well-known Noranda Caldera caldera. The multi-vent BRG mafic volcanic complex, developed on a monotonous sequence of tholeiitic VMS deposits Greenstone belt basalts, forming a submarine plain, and experienced a first major collapse that created the giant Misema Archean Caldera (80 km in diameter). An endogenic dyke swarm intruded the synvolcanic fractures and an under- Blake River Group lying magma chamber developed. Major volcaniclastic units were generated by local volcanic centers and Abitibi greenstone belt summit calderas formed along the outer and inner ring faults.
    [Show full text]
  • The Volcanic Setting of VMS and SMS Deposits: a Review
    The following document is a pre-print version of: Ross P-S, Mercier-Langevin P (2014) The volcanic setting of VMS and SMS deposits: a review. Geoscience Canada, DOI 10.12789/geocanj.2014.41.045 The volcanic setting of VMS and SMS deposits: a review Pierre-Simon Ross* Institut national de la recherche scientifique, centre Eau Terre Environnement, 490 rue de la Couronne, Québec (Qc) G1K 9A9, Canada, Ph. 418-654-3773, Email [email protected] * Corresponding author Patrick Mercier-Langevin Geological Survey of Canada, 490 rue de la Couronne, Québec (QC), G1K 9A9, Canada [email protected] SUMMARY RÉSUMÉ Volcanogenic massive sulfide (VMS) deposits and Les gisements de sulfures massifs volcanogènes (SMV) seafloor massive sulfide (SMS) deposits have a spatial et leurs équivalents actuels au fonds des mers ont une and genetic connection with contemporaneous connexion spatiale et génétique avec le volcanisme. La volcanism. The control exerted by the volcanic succession volcanique – composition, architecture, succession (e.g., rock type, architecture and facies) on faciès – exerce un contrôle important sur la nature et le the nature and style of the ore and alteration (e.g., style de minéralisation et d’altération hydrothermale subsea-floor replacement vs. exhalative, or discordant (p. ex. minéralisation mise en place par remplacement vs. conformable) is significant, making it imperative to sous le fond marin vs. exhalative; altération understand the local volcanology in developing better discordante ou plus concordante). Il est donc impératif genetic and exploration models. de connaître la volcanologie des roches encaissantes pour développer de meilleurs modèles génétiques et Three deposit groupings that cover a good proportion d’exploration.
    [Show full text]
  • 15. Petrology of Associated Igneous Rocks
    15. Petrology of Associated Igneous Rocks By W. Ian Ridley 15 of 21 Volcanogenic Massive Sulfide Occurrence Model Scientific Investigations Report 2010–5070–C U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior KEN SALAZAR, Secretary U.S. Geological Survey Marcia K. McNutt, Director U.S. Geological Survey, Reston, Virginia: 2012 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. For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprod To order this and other USGS information products, visit http://store.usgs.gov Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any copyrighted materials contained within this report. Suggested citation: Ridley, W. Ian, 2012, Petrology of associated igneous rocks in volcanogenic massive sulfide occurrence model: U.S. Geological Survey Scientific Investigations Report 2010–5070 –C, chap. 15, 32 p. 229 Contents Importance of Igneous Rocks to Deposit Genesis ...............................................................................231 Rock Names ................................................................................................................................................231
    [Show full text]