Airborne Magnetic Survey, Shaded Colour Image of the Second Vertical
Total Page:16
File Type:pdf, Size:1020Kb
THESE TERMS GOVERN YOUR USE OF THIS DOCUMENT Your use of this Ontario Geological Survey document (the “Content”) is governed by the terms set out on this page (“Terms of Use”). By downloading this Content, you (the “User”) have accepted, and have agreed to be bound by, the Terms of Use. Content: This Content is offered by the Province of Ontario’s Ministry of Northern Development and Mines (MNDM) as a public service, on an “as-is” basis. Recommendations and statements of opinion expressed in the Content are those of the author or authors and are not to be construed as statement of government policy. You are solely responsible for your use of the Content. You should not rely on the Content for legal advice nor as authoritative in your particular circumstances. Users should verify the accuracy and applicability of any Content before acting on it. MNDM does not guarantee, or make any warranty express or implied, that the Content is current, accurate, complete or reliable. MNDM is not responsible for any damage however caused, which results, directly or indirectly, from your use of the Content. MNDM assumes no legal liability or responsibility for the Content whatsoever. Links to Other Web Sites: This Content may contain links, to Web sites that are not operated by MNDM. Linked Web sites may not be available in French. MNDM neither endorses nor assumes any responsibility for the safety, accuracy or availability of linked Web sites or the information contained on them. The linked Web sites, their operation and content are the responsibility of the person or entity for which they were created or maintained (the “Owner”). Both your use of a linked Web site, and your right to use or reproduce information or materials from a linked Web site, are subject to the terms of use governing that particular Web site. Any comments or inquiries regarding a linked Web site must be directed to its Owner. Copyright: Canadian and international intellectual property laws protect the Content. Unless otherwise indicated, copyright is held by the Queen’s Printer for Ontario. It is recommended that reference to the Content be made in the following form: Ontario Geological Survey 2013. Airborne magnetic survey, shaded colour image of the second vertical derivative of the gradient-enhanced residual magnetic field and Keating coefficients, Latchford area— Purchased data; Ontario Geological Survey, Map 60 419, scale 1:50 000. Use and Reproduction of Content: The Content may be used and reproduced only in accordance with applicable intellectual property laws. Non-commercial use of unsubstantial excerpts of the Content is permitted provided that appropriate credit is given and Crown copyright is acknowledged. Any substantial reproduction of the Content or any commercial use of all or part of the Content is prohibited without the prior written permission of MNDM. Substantial reproduction includes the reproduction of any illustration or figure, such as, but not limited to graphs, charts and maps. Commercial use includes commercial distribution of the Content, the reproduction of multiple copies of the Content for any purpose whether or not commercial, use of the Content in commercial publications, and the creation of value-added products using the Content. Contact: FOR FURTHER PLEASE CONTACT: BY TELEPHONE: BY E-MAIL: INFORMATION ON The Reproduction of MNDM Publication Local: (705) 670-5691 the EIP or Content Services Toll-Free: 1-888-415-9845, ext. 5691 [email protected] (inside Canada, United States) The Purchase of MNDM Publication Local: (705) 670-5691 MNDM Publications Sales Toll-Free: 1-888-415-9845, ext. 5691 [email protected] (inside Canada, United States) Crown Copyright Queen’s Printer Local: (416) 326-2678 Toll-Free: 1-800-668-9938 [email protected] (inside Canada, United States) SURVEY PARAMETERS 79°57'23" 55' 50' 45' 40' 35' 30' 79°28'53" 580000 m 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 600000 m 01 02 03 04 05 06 07 08 09 10 11 12 13 614000 m 47°13'07" 47°11'48" AIRCRAFT Rory Type: Aerospatiale AS350BA (Block 1) The Lake Registration: C-GHSM Three Cliff Lake . P Type: Aerospatiale AS350B (Block 2) Sisters T Geoffrey IT Registration: C-FDYS Ontario Geological Survey IM Lake L 587 S . M IE P MAGNETOMETER 5229000 m Whitney L T o 5229000 m IL ST MAP 60 419 G E n Type: Geometrics caesium-vapour (Block 1) Lake B t re Silver Centre Scintrex CS2 caesium-vapour (Block 2) a l Sensitivity: 0.02 nT (Block 1) Gilbert 0.01 nT (Block 2) AIRBORNE MAGNETIC SURVEY Lake Sample interval: 10 readings per second 11 28 28 Sensor location: 15 m below aircraft (Block 1) Snare Fourclaim 0 m below aircraft (Block 2) Shaded colour image of the second vertical Lake Sensor separation: 13.2 m (Block 2) derivative of the gradient-enhanced residual Babcock Island NAVIGATION AND DATA ACQUISITION SYSTEMS magnetic field and Keating coefficients GPS receiver: Novatel OEM4-G2-3151W (Block 1) Pike Lake Rib Lake 27 27 Ashtec Glonass GG24 (Block 2) Lundy Lake GPS sample interval: 5 readings per second (Block 1) CLIFF LAKE Tooth 2 readings per second (Block 2) CONSERVATION RESERVE Lake Radar altimeter: Terra 3000/TRI-40 (Block 1) Thieving Bear Oxbow Honeywell AA 330 (Block 2) Lake Lake Radar sample interval: 5 readings per second (Block 1) Purchased Data James 26 26 Tyndall Lake 2 readings per second (Block 2) Lake Guidance system: Geotech (Block 1) Scale 1:50 000 PNAV 2100 (Block 2) Digital acquisition system: Geotech (Block 1) 1 km 0 1 2 km Fugro Helidas (Block 2) 25 25 BASE STATION Contact 10' Type: Geometrics caesium-vapour (Block 1) Lake R Scintrex CS2 caesium-vapour (Block 2) NTS References: 31 L/13, 14; 31 M/3, 4 Granite iv Magnetometer sample interval: 1 reading per second Lake Price's e GPS sample interval: 1 reading per second 10' Lake r McNab Creek Creek © Queen's Printer for Ontario, 2013. 24 Lake 24 SURVEY SPECIFICATIONS k e Survey date: December 16, 2005 to January 6, 2006 (Block 1) re This map is published with the permission of the Director, Black C February 10, 2006 to March 6, 2006 (Block 2) Net Little Duck Nominal aircraft terrain clearance: 80 m (Block 1) Ontario Geological Survey. Lake Lake Trout Lake Sandstone 30 m (Block 2) BANTING TP. Traverse line spacing: 50 m (Block 1) 23 23 75 m (Block 2) Little Mud Control line spacing: 500 m (Block 1) Owaissa Myth Little Lake 1000 m (Block 2) Lake Lake Mountain Traverse line direction: N44°E (Block 1) BEST TP. Lake North-South (Block 2) Watson's Control line direction: N134°E (Block 1) Petraut Lake 22 Duncan Lake Spruce 22 East-West (Block 2) Lake CASSELS TP. Lake Jackpine STRATHY TP. Lake CO-ORDINATE SYSTEM Projection: Universal Transverse Mercator Datum: NAD83 Hook Ferguson Lake Central meridian: 93°00' W (UTM zone 15N) 21 CHAMBERS TP. Lake Monty 21 Central scale factor: 0.9996 Net Bernice Owaissa Lake Lake False easting: 500 000 m Lake False northing: 0 m Lorrain Lake Data purchased from: Amador Gold Corp. (Block 1) (Banting–Chambers property) 20 20 Temex Resources Corp. (Block 2) (Cobalt area) ay Gorrie d ri Lake F Hansen MATABITCHUAN Lake Sauvé RIVER Location map 1 cm equals 15 km Pishabo CONSERVATION Lake RESERVE Temagami Lake 19 19 Kanichee Lake North Fourbass Lake LEGEND Alfreda DESCRIPTIVE NOTES Lake KEATING COEFFICIENTS Positive correlation Negative correlation Introduction 18 18 90% This map was compiled from two proprietary airborne surveys Bogie Obashkong purchased by the Ontario Ministry of Northern Development Lake Lake and Mines. These surveys were flown using a Fugro Midas Copper 85% magnetic horizontal gradiometer-equipped aircraft and a Net Lake Lake Geotech helicopter-borne magnetometer-equipped aircraft. Maureen Lorrain The aircraft were also equipped with GPS navigation systems 17 Lake Lake 17 80% Gosselin and digital data acquisition systems. Lake 11 Arsenic Lake 75% Crash Second Vertical Derivative of the Magnetic Field Lake 16 16 The second vertical derivative values of the magnetic field were computed directly from the gridded residual magnetic Cooke Lake intensity data using a fast Fourier transform, combining the Young 05' SHADED IMAGE SUN ANGLE transfer functions of the second vertical derivative and a Lake 30 m Upward Continuation operator. The Upward Contin- Doris Lake Cassels Lake uation was applied in order to attenuate unwanted high 15 15 Illumination Illumination frequencies enhanced by the derivative operator. 05' Blueberry Inclination = 45° Declination = 0° Lake Golden The shaded relief parameters are: Lake Illumination inclination: 45° Illumination declination: 0° Leroy O'Connor Lake 14 Lake 14 Using the means for all blocks, the magnetic declination on Link Lake January 30, 2006 for the centre of the survey area was 11.5°W and magnetic inclination was 73.3°N. Magnetic field strength Sutton N was 56 565 nT (calculated using IGRF). Lake SOUTH LORRAIN TP. Cooper Lake Temagami CASSELS TP. 13 13 Plan view Keating Correlation Coefficients STRATHY TP. CHAMBERS TP. ELDRIDGE TP. Possible kimberlite targets have been identified from the residual Turtle Lake W E magnetic intensity data, based on the identification of roughly circular anomalies. This procedure was automated by using a STRATHCONA TP. RIDDELL TP. known pattern-recognition technique (Keating 1995), which 12 Tetapaga Lake 12 consists of computing, over a moving window, a first-order BRIGGS TP. regression between a vertical cylinder model anomaly and the Bell Island Pingue S gridded magnetic data. Only the results where the absolute Lake value of the correlation coefficient is above a threshold of 75% O'Connor Pleasant Lake FINLAYSON were retained.