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REPORT ON A HELICOPTER-BORNE VERSATILE TIME DOMAIN ELECTROMAGNETIC (VTEM) AND AEROMAGNETIC GEOPHYSICAL SURVEY

REPORT ON A HELICOPTER-BORNE VERSATILE TIME DOMAIN ELECTROMAGNETIC (VTEM) AND AEROMAGNETIC GEOPHYSICAL SURVEY Cement Block Sudbury, Ontario For: Goldtrain Resources Inc. By: Geotech Ltd. 24 Industrial
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REPORT ON A HELICOPTER-BORNE VERSATILE TIME DOMAIN ELECTROMAGNETIC (VTEM) AND AEROMAGNETIC GEOPHYSICAL SURVEY Cement Block Sudbury, Ontario For: Goldtrain Resources Inc. By: Geotech Ltd. 24 Industrial Parkway North Aurora, Ont., CANADA, L4G 4C4 Tel: Fax: Survey flown during February 21 Project 123 February, 21 TABLE OF CONTENTS Executive Summary... ii 1. INTRODUCTION General Considerations Survey and System Specifications Topographic Relief and Cultural Features DATA ACQUISITION Survey Area Survey Operations Flight Specifications Aircraft and Equipment Survey Aircraft Electromagnetic System Airborne magnetometer Radar Altimeter GPS Navigation System Digital Acquisition System Base Station PERSONNEL DATA PROCESSING AND PRESENTATION Flight Path Electromagnetic Data VTEM X Component Polarity Magnetic Data DELIVERABLES Survey Report Maps Digital Data...1. CONCLUSIONS AND RECOMMENDATIONS Conclusions Recommendations...19 LIST OF FIGURES Figure 1 - Property Location of the Cement Block... 1 Figure 2 Cement Block, showing the magnetic base station location on Google Earth... 2 Figure 3 Cement Block flight path over a Google Earth Image Figure 4 - VTEM Configuration, with magnetometer.... Figure - VTEM Waveform & Sample Times... Figure - VTEM System Configuration... 8 Figure 7 - VTEM Z and X Component data Figure 8 - VTEM X Component Polarity Convention for the Cement Block LIST OF TABLES Table 1 - Survey Specifications... 4 Table 2 - Survey schedule... 4 Table 3 - Decay Sampling Scheme... 7 Table 4 - Acquisition Sampling Rates... 9 Table - Geosoft GDB Data Format... 1 APPENDICES A. Survey location maps... B. Survey Block Coordinates... C. VTEM Waveform... D. Geophysical Maps... E. Generalized Modelling Results of the VTEM System Report on Airborne Geophysical Survey for Goldtrain Resources Inc. i REPORT ON A HELICOPTER-BORNE VERSATILE TIME DOMAIN ELECTROMAGNETIC (VTEM) AND AEROMAGNETIC SURVEY Executive Summary Cement Block Sudbury, Ontario During February 2 nd to 7 th, 21 Geotech Ltd. carried out a helicopter-borne geophysical survey over the Cement Block situated near Sudbury Ontario, Canada. Principal geophysical sensors included a versatile time domain electromagnetic (VTEM) system, and a caesium magnetometer. Ancillary equipment included a GPS navigation system and a radar altimeter. A total of 21 line-kilometres were planned to be flown. The survey operations were based out of the town of Sudbury located in the province of Ontario. In-field data quality assurance and preliminary processing were carried out on a daily basis during the acquisition phase. Preliminary and final data processing, including generation of final digital data and map products were undertaken from the office of Geotech Ltd. in Aurora, Ontario. The processed survey results are presented as electromagnetic stacked profiles of the B-field Z Component and db/dt X and Z Components, and as colour grids of a B-Field Z Component Channel, and Total Magnetic Intensity. Digital data includes all electromagnetic and magnetic products, plus ancillary data including the waveform. The survey report describes the procedures for data acquisition, processing, final image presentation and the specifications for the digital data set. No Interpretation summary is included with this report Report on Airborne Geophysical Survey for Goldtrain Resources Inc. ii 1. INTRODUCTION 1.1 General Considerations Geotech Ltd. performed a helicopter-borne geophysical survey over the Cement Block located northeast of the town of Sudbury, Ontario, Canada (Figure 1). Brian Wright, President, acted on behalf of Goldtrain Resources Inc. during the data acquisition and data processing phases of this project. The geophysical surveys consisted of helicopter borne EM using the versatile time-domain electromagnetic (VTEM) system with Z and X component measurements and aeromagnetics using a caesium magnetometer. A total of 21.8 line-km of geophysical data were acquired during the survey. The survey area is shown in Figure 2 and Figure 3. The crew was based out of Sudbury, Ontario for the acquisition phase of the survey. Survey operations started on February 2 nd and completed on February 7 th, 21. Data quality control and quality assurance, and preliminary data processing were carried out on a daily basis during the acquisition phase of the project. Final data processing followed immediately after the end of the survey. Final reporting, data presentation and archiving were completed from the Aurora office of Geotech Ltd. in February, 21. Figure 1 - Property Location of the Cement Block Report on Airborne Geophysical Survey for Goldtrain Resources Inc. 1 1.2 Survey and System Specifications The Cement Block (4.29'N, 'W) is located approximately 7 kilometres north-east of the town of Sudbury, Ontario and 84 kilometres north-west of the town of North Bay, Ontario (Figure 2). Figure 2 Cement Block, showing the magnetic base station location on Google Earth. The Cement Block was flown in a north-south (N E / N 18 E) flight direction, with a traverse line spacing of 1 metres wherever possible. Tie lines were flown perpendicular to the traverse lines at a spacing of 13 metres in an east-west (N 9 E / N 27 E) direction. For more detailed information on the flight spacing and direction see Table Report on Airborne Geophysical Survey for Goldtrain Resources Inc. 2 1.3 Topographic Relief and Cultural Features Topographically, the Cement Block exhibits a moderate relief, with an elevation ranging from 2 to 41 metres above sea level over an area of 27.8 square kilometres (see Figure 3). The survey block covers numerous small lakes such as Archarnd Lake, North Silver Lake and Brightwater Lake. The block also covers one large lake (Manitou Lake) situated directly in the center of the block, running and a north-south direction. There are numerous buildings found along the Manitou Lake, as well as Wawiashkashi Lake located directly south of the block. Roads are also running throughout the survey block, one along the west edge of Manitou Lake, one through the south-western portion of the block, and one running through the eastern portion of the block. Special care is recommended in identifying these roads, and buildings, along with any other potential cultural features from other sources that might be recorded in the data. The block is covered by 11 Ontario mining claims, which are shown in Appendix A, and are plotted on all maps. The survey area is covered by NTS (National Topographic Survey) of Canada sheets 41I1. Figure 3 Cement Block flight path over a Google Earth Image Report on Airborne Geophysical Survey for Goldtrain Resources Inc. 3 2. DATA ACQUISITION 2.1 Survey Area The survey block (see Figure 3 and Appendix A) and general flight specifications are as follows: Table 1 - Survey Specifications Survey block Cement Traverse Line spacing (m) Area (Km 2 ) Planned 1 Line-km Actual Linekm Flight direction Line numbers Traverse: N E / N 18 E L1 L Tie: N 9 E / N 27 E T29 T293 TOTAL Survey block boundaries co-ordinates are provided in Appendix B. 2.2 Survey Operations Survey operations were based out of the Comfort Inn East in the town of Sudbury, Ontario from February 2 nd to 7 th 21. The following table shows the timing of the flying. Table 2 - Survey schedule Date Flight # Flown km Block Crew location Comments Sudbury ON System installation Sudbury ON Test Flight Sudbury ON Technical Issues Sudbury ON Technical Issues Sudbury ON Test Flight ,2 21 Cement Sudbury ON Production- Job Complete 1 Note: Actual Line kilometres represent the total line kilometres in the final database. These line-km normally exceed the Planned line-km, as indicated in the survey NAV files Report on Airborne Geophysical Survey for Goldtrain Resources Inc. 4 2.3 Flight Specifications During the survey of the Cement Block the helicopter was maintained at a mean height of 77.4 metres above the ground with a nominal survey speed of 8 km/hour. This allowed for a nominal EM sensor terrain clearance of 4.4 metres and a magnetic sensor clearance of 4.4 metres. The data recording rates of the data acquisition was.1 second for electromagnetics, magnetometer and.2 second for altimeter and GPS. This translates to a geophysical reading about every 2 metres along flight track. Navigation was assisted by a CDGPS receiver and data acquisition system, which reports GPS co-ordinates as latitude/longitude and directs the pilot over a pre-programmed survey grid. The operator was responsible for monitoring of the system integrity. He also maintained a detailed flight log during the survey, tracking the times of the flight as well as any unusual geophysical or topographic feature. On return of the aircrew to the base camp the survey data was transferred from a compact flash card (PCMCIA) to the data processing computer. The data were then uploaded via ftp to the Geotech office in Aurora for daily quality assurance and quality control by qualified personnel, operating remotely. 2.4 Aircraft and Equipment Survey Aircraft The survey was flown using a Eurocopter Aerospatiale (Astar) 3 B3 helicopter, registration C-GEOZ. The helicopter is owned and operated by Geotech Aviation out of Sudbury, Ontario. Installation of the geophysical and ancillary equipment was carried out by Geotech Ltd Electromagnetic System The electromagnetic system was a Geotech Time Domain EM (VTEM) system. The configuration is as indicated in Figure 4 below. The standard VTEM Receiver and transmitter coils are concentric-coplanar and Z-direction oriented. The receiver system for the project also included a coincident-coaxial X-direction sensor to measure the in-line db/dt and calculate B-Field responses. All loops were towed at a mean distance of 3 metres below the aircraft as shown in Figure and Figure. The receiver decay recording scheme is shown diagrammatically in Figure Report on Airborne Geophysical Survey for Goldtrain Resources Inc. Figure 4 - VTEM Configuration, with magnetometer. Figure - VTEM Waveform & Sample Times The VTEM decay sampling scheme is shown in Table 3 below. Thirty-two time measurement gates were used for the final data processing in the range from 9 to 73 µ sec, as shown in Table Report on Airborne Geophysical Survey for Goldtrain Resources Inc. Table 3 - Decay Sampling Scheme 2 VTEM Decay Sampling Scheme Index Middle Start End Window Microseconds ,1 94 1, ,11 1,8 1, ,333 1,247 1, ,31 1,432 1, ,7 1,4 1, ,21 1,891 2, ,323 2,172 2, ,7 2,49 2, ,3 2,8 3, ,21 3,292 3, ,42 3,781 4, ,41 4,341 4, ,333 4,987, ,12,729, ,3,81 7, ,83 7, 8,8 1, ,28 8,8 9,977 1, ,7 9,977 11,48 1, ,2 11,48 13,11 1,73 2 Note: Measurement times-delays are referenced to time-zero marking the end of the transmitter current turn-off, as illustrated in Figure and Appendix C Report on Airborne Geophysical Survey for Goldtrain Resources Inc. 7 VTEM system parameters: Transmitter Section - Transmitter coil diameter: 2. m - Number of turns: 4 - Transmitter base frequency: 3 Hz - Peak current: A - Pulse width: 7.17 ms - Duty cycle: 43 % - Wave form shape: trapezoid - Peak dipole moment: 384, 4 nia - Nominal terrain clearance:4.4 metres - Effective coil area: 8 m 2 Receiver Section X-Coil - X Coil diameter:.32 m - Number of turns: 24 - Effective coil area: 19.9 m 2 Z-Coil - Z-Coil coil diameter: 1.2 m - Number of turns: 1 - Effective coil area: m 2 Magnetometer - Nominal terrain clearance: 4.4 metres Gps Antenna Magnetic sensor 13 m Radar Altimeter Antenna EM Transmitter Coil EM Receiver Coil (X-Z) 42 m 3 m 23 m Figure - VTEM System Configuration Report on Airborne Geophysical Survey for Goldtrain Resources Inc. 8 2.4.3 Airborne magnetometer The magnetic sensor utilized for the survey was a Geometrics optically pumped caesium vapour magnetic field sensor, mounted on the EM bird, 13 metres below the helicopter, as shown in Figure. The sensitivity of the magnetic sensor is.2 nanotesla (nt) at a sampling interval of.1 seconds. The magnetometer sends the measured magnetic field strength as nanotesla to the data acquisition system via the RS-232 port Radar Altimeter A Terra TRA 3/TRI 4 radar altimeter was used to record terrain clearance. The antenna was mounted beneath the bubble of the helicopter cockpit (Figure ) GPS Navigation System The navigation system used was a Geotech PC14 based navigation system utilizing a NovAtel s CDGPS (Canada-Wide Differential Global Positioning System Correction Service) enable OEM4-G2-311W GPS receiver, Geotech navigate software, a full screen display with controls in front of the pilot to direct the flight and an NovAtel GPS antenna mounted on the helicopter tail (Figure ). As many as 11 GPS and two CDGPS satellites may be monitored at any one time. The positional accuracy or circular error probability (CEP) is 1.8 m, with CDGPS active, it is 1. m. The co-ordinates of the block were set-up prior to the survey and the information was fed into the airborne navigation system Digital Acquisition System A Geotech data acquisition system recorded the digital survey data on an internal compact flash card. Data is displayed on an LCD screen as traces to allow the operator to monitor the integrity of the system. The data type and sampling interval as provided in Table 4. Table 4 - Acquisition Sampling Rates DATA TYPE TDEM Magnetometer GPS Position Radar Altimeter SAMPLING.1 sec.1 sec.2 sec.2 sec Report on Airborne Geophysical Survey for Goldtrain Resources Inc. 9 2. Base Station A combined magnetometer/gps base station was utilized on this project. A Geometrics Caesium vapour magnetometer was used as a magnetic sensor with a sensitivity of.1 nt. The base station was recording the magnetic field together with the GPS time at 1 Hz on a base station computer. The base station magnetometer sensor was installed in a open field 3km south-south-west of the Sudbury Airport ( N, W); away from electric transmission lines and moving ferrous objects such as motor vehicles (see Figure 2). The base station data were backed-up to the data processing computer at the end of each survey day Report on Airborne Geophysical Survey for Goldtrain Resources Inc. 1 3. PERSONNEL The following Geotech Ltd. personnel were involved in the project. Field: Project Manager: Data QA/QC: Crew chief: System Operators: Adrian Sarmasag (office) Neil Fiset (office) Roger Leblanc Eric MacNeill The survey pilot and the mechanical engineer were employed directly by the helicopter operator Geotech Aviation Pilot: Mechanical Engineer: Brad MacRae Oleg Babishin Office: Preliminary Data Processing: Final Data Processing: Final Data QA/QC: Reporting/Mapping: Neil Fiset Neil Fiset Harish Kumar Eric Steffler Data acquisition phase was carried out under the supervision of Andrei Bagrianski, P. Geo, Surveys Manager. Processing phase was carried out under the supervision of Gord Smith, Manager of Data Processing. The overall contract management and customer relations were by Paolo Berardelli Report on Airborne Geophysical Survey for Goldtrain Resources Inc. 11 4. DATA PROCESSING AND PRESENTATION Data compilation and processing were carried out by the application of Geosoft OASIS Montaj and programs proprietary to Geotech Ltd. 4.1 Flight Path The flight path, recorded by the acquisition program as WGS 84 latitude/longitude, was converted into the NAD83 Datum, UTM Zone 17 North coordinate system in Oasis Montaj. The flight path was drawn using linear interpolation between x, y positions from the navigation system. Positions are updated every second and expressed as UTM easting s (x) and UTM northing s (y). 4.2 Electromagnetic Data A three stage digital filtering process was used to reject major sferic events and to reduce system noise. Local sferic activity can produce sharp, large amplitude events that cannot be removed by conventional filtering procedures. Smoothing or stacking will reduce their amplitude but leave a broader residual response that can be confused with geological phenomena. To avoid this possibility, a computer algorithm searches out and rejects the major sferic events. The filter used was a 1 point non-linear filter. The signal to noise ratio was further improved by the application of a low pass linear digital filter. This filter has zero phase shift which prevents any lag or peak displacement from occurring, and it suppresses only variations with a wavelength less than about 1 second or 1 metres. This filter is a symmetrical 1 sec linear filter. The results are presented as stacked profiles of EM voltages for the time gates, in linear - logarithmic scale for the B-field Z component and db/dt responses in the Z and X components. Figure 7 - VTEM Z and X Component data Report on Airborne Geophysical Survey for Goldtrain Resources Inc. 12 Generalized modeling results of VTEM data, are shown in Appendix E. Graphical representations of the VTEM transmitter input current and the output voltage of the receiver coil are shown in Appendix C VTEM X Component Polarity VTEM X component data do not exhibit maxima or minima above conductors; in fact they produce cross-over type anomalies (Figure 7). The crossover polarity sign convention for VTEM X component polarity is according to the right hand rule for multi-component transient electromagnetic methods. For the north-south lines of the Cement Block the sign convention for the X in-line component crossover is positive-negative pointing south to north for tabular conductor s perpendicular to the profile (Figure 8). Similarly, for the east-west tie lines, the X Component polarity is positive to negative pointing east to west. X component data for alternating/opposite flight directions have been reversed (multiplied by negative one) in the final database (SFx_Rev and BFx_Rev channels) to account for this polarity convention. Figure 8 - VTEM X Component Polarity Convention for the Cement Block Report on Airborne Geophysical Survey for Goldtrain Resources Inc. 13 4.3 Magnetic Data The processing of the magnetic data involved the correction for diurnal variations by using the digitally recorded ground base station magnetic values. The base station magnetometer data was edited and merged into the Geosoft GDB database on a daily basis. The aeromagnetic data was corrected for diurnal variations by subtracting the observed magnetic base station deviations. Tie line levelling was carried out by adjusting intersection points along traverse lines. A micro-levelling procedure was applied to remove persistent low-amplitude components of flight-line noise remaining in the data. The corrected magnetic data was interpolated between survey lines using a random point gridding method to yield x-y grid values for a standard grid cell size of approximately.2 inches at the mapping scale. The Minimum Curvature algorithm was used to interpolate values onto a rectangular regular spaced grid Report on Airborne Geophysical Survey for Goldtrain Resources Inc. 14 . DELIVERABLES.1 Survey Report.2 Maps The survey report describes the data acquisition, processing, and final presentation of the survey results. The survey report is provided in two paper copies and digitally in PDF format. Final maps were produced at scale of 1:1, for best representation of the survey size and line spacing. The coordinate/projection system used was NAD 83 Datum, UTM Zone 17 North. All maps show the flight path trace and topographic data; latitude and longitude are also noted on maps. Mineral claims, provided by the Ontario Ministry of Northern Development and Mines, are also presented on each map. The preliminary and final results of the survey are presented as EM profiles, a late-time gate gridded EM channel, and a color magnetic TMI contour map. The following maps are presented on paper;.3 Digital Data VTEM db/dt profiles Z Component, Time Gates ms in linear logarithmic scale. Total magnetic intensity (TMI) color image and contours. Two copies of the data and maps on DVD were prepared to accompany the report. Each DVD conta
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