8 2 E L. Geophysical Exploration Report of 18282EL, Wase LGA, Plateau State. BRIGO MINING COMPANY LTD.

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1 1 Geophysical Exploration Report of 18282EL, Wase LGA, Plateau State. BRIGO MINING COMPANY LTD. 8 2 Electromagnetic and Induced Polarization Exploration Report 8 2 E L By: Dr. Oladele Olaniyan GISL, Abuja

2 Executive Summary Geodel integrated Systems Ltd (GISL) was commissioned by BRIGO MINING COMPANY LTD ( BMCL ) to undertake preliminary exploration programs and compile Preliminary feasibility Study (PFS) for the Lead Zinc Project at the 18282EL in Safiyo, Wase LGA, Plateau State, Nigeria. Between October 15th and 17th, 2014, a preliminary reconnaissance survey was conducted at the project site, to i) Assess the viability of the exploration license areas for lead-zinc and other sulfide mineralisations ii) Define the host rocks, mineralization styles and dominant trend of mineralization iii) Obtain and analyze some selected samples from the sites iv) Design a systematic mineral exploration procedure for lead and other associated metallic mineralization. In November 2014, GISL planned and conducted an electromagnetic survey (EM) over a 1 km by 1 km area within the EL, to delineate conductive locations and structures, that might be related or controlling the lead zinc mineralisations within the area. The survey was undertaken with an APEX Maxmin horizontal loop electromagnetic equipment at a loop separation of 100 m and 50 m respectively. About 2,000 meter cumulative length of conductors was interpreted from the five frequencies EM survey data. In January 2015, the Indued polarization survey was conducted across the interpreted EM anomalies to further define the source and likely geometry of the conductive structures and bodies. This survey utilizes the Time-domain GDD 5000 watt transmitter and the 16- channel receiver to map out the chargeable zone at the subsurface. Though this survey is still ongoing, the available results show good relationship between the magnetic, conductive and chargeable zones. Laboratory analysis of some hand samples of sulfide 1 P a g e

3 mineralisation grades between 60 to 80 percent of lead (Pb) around the area. This preliminary feasibility report summarizes the results of the exploration work done so far, and the projected resource estimate within the 1 km by 1 km survey area, for the purpose of a small scale mining lease application. 2 P a g e

4 Table of content Page 1.0 INTRODUCTION Location, accessibility 1.2 Climate and vegetation 1.3 Topography and Drainage 2.0 RECONNAISSANCE SURVEY ELECTROMAGNETIC SURVEY TIME DOMAIN INDUCED POLARIZATION PROSPECTIVITY MAPPING CONCLUSION AND RECOMMENDATIONS STATEMENT OF QUALIFICATION 33 3 P a g e

5 1.0 Introduction On the 2 nd June, 2014, the Federal Government of Nigeria through the Mining Cadastre Office granted the exploration license (EL) No 18282EL (Safiyo lead zinc prospect) to BRIGO MINING COMPANY LTD ( BMCL ) to explore for lead, zinc and copper in Plateau State, Nigeria. Plateau state is about 150 km east of the Federal capital territory (FCT) (Figure 1), and is notably rich in metallic and industrial minerals such as lead-zinc, copper, manganese, iron ore, niobium, columbite, tin ore occurring in hosted in intrusive granitoids, pegmatites, as well as sedimentary sequences EL Figure1: Map of Nigeria showing the location of the Federal capital territory, Plateau state and the location of the lead-zinc property of Brigo Nigeria Ltd. The 18282EL area is located on the eastern portion of Plateau state and lies within Longitudes E and 10.3E and Latitudes 9.2N and 9.225N (UTM) in the 1: map sheet No 192 of Bashar. The Safiyo Lead zinc property is defined by 4 vertices as shown in the table below. The area is about 7.2 sq km on land, 36 cadastral units. 4 P a g e

6 Table 1: Exploration License No: 18282EL vertex coordinates in GCS, WGS1984. FID State Topo Sheet (sq. km) Easting Northing Plateau Bashar (192) At the request of BRIGO MINING COMPANY LTD ( BMCL ), Geodel integrated Systems Ltd (GISL) designed and conducted a preliminary exploration over the Safiyo lead zinc prospect in Plateau State, Nigeria. approach is summarised in the chart presented below: GISL exploration Reconnaissance Survey Pre-existing data acquisition and processing- Airborne Magnetic data Preliminary ground truthing Laboratory analysis of random samples from mined pits Choice of survey area (1 km by 1 km) Electromagnetic Survey Survey planning Profile cutting Frequency domain electromagnetic survey EM Data Processing and Presentation Stacking and Plotting of the EM responses at five frequencies Conductivity mapping Geological interpretation IP survey Acquisition of Time domain polarization data over the interpreted electromagnetic anomalies IP data processing, plotting and interpretation Suitable Drill target selection Figure 2: GISL Lead zinc exploration program 5 P a g e

7 Figure 3: Survey layout and details of exploration license 18282EL 2.0 Reconnaissance Survey The exploration program commenced with the acquisition and processing of the existing airborne magnetic data, in order to understand regional trend of subsurface magnetic structures and lineament patterns of the area. The airborne magnetic data was acquired at 500 m line spacing and 200 m flight height. The total magnetic intensity field was acquired and it is mostly dominated by long wavelength, which indicates that most magnetic sources in the area are deep seated. Magnetic data enhancement techniques were used to amplify the short wavelength, to reflect the near surface lineaments. Both directional and normalised derivatives were computed- first and second vertical derivative, tilt angle, horizontal gradient and analytical signal. In all the computed magnetic derivatives, the dominant trend of magnetic lineament is north-northeast (NNE), with a northwest (NW) fault pattern. 1 km by 1 km area (in red box) was selected based on the interpreted subsurface 6 P a g e

8 magnetic lineament patterns. Thus, subsequent exploration was conducted investigation was conducted within the selected pilot area. Figure 3: The computed second vertical derivative of the total magnetic field over the EL. The red square box is the 1 km by 1 km area selected for the pilot study. In October 15-17, 2014, a preliminary ground truthing was conducted at the project site, to i) assess the viability of the exploration license areas for leadzinc and other sulfide mineralisations ii) define the host rocks, mineralization styles and dominant trend of mineralization iii) obtain and analyze some selected samples from the sites, and iv) design a systematic mineral exploration procedure for lead and other associated metallic mineralization. During this three day exercise, it was observed that the area is a sedimentary basin (Benue Trough) and there were no much rock exposures, except along river channel road cut and mined pits. Visit was paid to a local mining site, 7 P a g e

9 few kilometers to the east of the project area to study the subsurface geology and obtain samples for analysis. Figure 4: The sedimentary sequences at the site are made up of alternating sandstone, siltstone and mudstone. It was observed at the pit site that the disseminated and patchy lead-zinc mineralisation is hosted within the sandstone units of about 1m thickness as shown in the picture. 8 P a g e

Figure 4b: Reconnaissance Magnetic map showing all the BMCL lead prospects, locations of the mined pits (Figure 4a) and the 1km by 1 km selected for the pilot exploration. 3.

10 Figure 4b: Reconnaissance Magnetic map showing all the BMCL lead prospects, locations of the mined pits (Figure 4a) and the 1km by 1 km selected for the pilot exploration. 3.0 Electromagnetic Survey procedure In November 2014, GISL planned and conducted an electromagnetic survey (EM) over a 1 km by 1 km area within the EL, to delineate conductive locations and structures, that might be related or controlling the lead zinc mineralisations within the area. The survey was undertaken with APEX MaxMin horizontal loop electromagnetic equipment at a loop separation of 100 m and 50 m respectively (Figure 6). Multiple and parallel EM conductors were interpreted cumulating to about 2,780 meter length of conductors from the five frequencies EM survey data. 9 P a g e

11 Figure 5: Horizontal loop EM survey design in NW direction across the dominant magnetic trend. Figure 6: HLEM data acquisiton along the survey line with MaxMin transmitter and receiver. 10 P a g e

12 EM Data presentation and interpretation The horizontal co-planar loop EM data of each line are presented in stacked profile plans of the inphase and quadrature components for each frequency and coil separation. The quadrature is largely unaffected by the coil separation and orientation errors, and does respond better to very poor conductors. These two facts have proven very useful in the evaluating and outlining of the weak to moderately high conductors at the project site as described below. Figure 7: EM interpretation along one of the survey profiles. Plot of successive survey line data in figures below, highlights the continuity of conductors across profiles at the subsurface. 11 P a g e

13 Figure 8: the stacked sections of the Northern sections. 12 P a g e

14 Figure 9: the stacked section of the southern profiles. Plot of successive survey line data in figures below, highlights the continuity of conductors across profiles at the subsurface. The total cumulative length of the interpreted conductors is about 2.6 km as shown in the table below: 13 P a g e

15 Figure10: Conductivity mapping and estimation of length of the conductors. The quadrature responses at the 222 Hz and 444 Hz frequencies were gridded at one meter interval using the kriging method, to help understand the spatial distribution and continuity of the Interpreted conductive structures at the subsurface. The black and yellow lineaments and patterns are the low / negative quadrature responses, which represent the locations of conductors that will be further investigated and explained. 14 P a g e

Figure 11: Gridded map of the quadrature response at frequency 222 Hz The quadrature responses at the 444 Hz frequency were plotted on the processed magnetic derivative.

16 Figure 11: Gridded map of the quadrature response at frequency 222 Hz The quadrature responses at the 444 Hz frequency were plotted on the processed magnetic derivative. This was undertaken to highlight the correlation between the Interpreted conductors and the magnetic lineaments locations. In the second derivative of the magnetic field, the inflection point between the highs (pink) and low (blue) are the locations of the magnetic source, while low/negative response in the HLEM data represents locations of conductors. Locations favorable for these two interpretative indexes have been delineated by red and green broken lines at different level of confidence. The locations delineated with red lines are linear conductors coinciding with locations of magnetic lineaments, while the greens are conductive locations that fall within the corridor of a magnetic lineament. 15 P a g e

17 Figure12: EM and Magnetic data integration. 4.0 INDUCED POLARIZATION SURVEY As a follow up to the geophysical electromagnetic survey, Time Domain Induced Polarization (TDIP) survey was conducted for BRIGO MINING COMPANY LTD (BMCL), across the interpreted electromagnetic anomalies. The ground geophysical survey was conducted by GISL crew during the months of February and March in The acquired IP data were processed and plotted to generate 2-D pseudosections showing the variation of the IP chargeability, resistivity and the metal factor coefficient computed by dividing the duo. Time domain, IP data were collected along the EM profiles using GDD 5000 watt transmitter and 16-channel receiver figure 13 and 14. The setup utilized pole-dipole array, conductor cables, two steel current electrodes and eight 16 P a g e

non-polarizable copper sulphate electrode pots spaced at 20 m apart, while the first current electrode was always put at infinity (~five times the spacing).

18 non-polarizable copper sulphate electrode pots spaced at 20 m apart, while the first current electrode was always put at infinity (~five times the spacing). The current was injected with a 2 seconds on and 2 seconds off duty cycle into the ground via a 5000 watt transmitter (Tx), while the receiver measures the decay of the primary voltage. 50 readings were stacked to improve the signal/ noise ratio. Figure 13: Field set up of the GDD 5000 Transmitter and 16C receiver. The IP reading for each surveying day were downloaded to a computer and entered into a database on a daily basis. Quality control of the acquired data was done using the Geosoft oasis Montaj IP module. Where the decay curve and the noise level of each channel are reviewed and noisy channels were eliminated. 17 P a g e

19 Figure 14: The IP data were acquired over the interpreted EM anomalous bodies in the NW direction. The red points are the electrode locations along the survey profile, at a spacing of 20 m. The background map is the EM quadrature responses at 444 Hz, the black- yellow are the conductive zones and structures, while the pink area are not conductive. IP Data Presentation 1. Pseudosection The IP chargeability and resistivity data pseudosections were plotted using the IP module of Oasis Montaj software. The software contours the IP chargeability values acquired at different depths and locations, and also assign a color scale as defined by the user. The uppermost image is the IP chargeability plot, middle is the resistivity, while the lower section is the metal factor coefficient. This plot presents a vertical section showing the variation of IP chargeability and conductivity of materials at the subsurface along the survey profile. 18 P a g e

20 On the pseudosection, the high IP chargeability portions are in color pink, while the low IP areas are in green-blue color. In the resistivity section, the low areas are in blues, while the pink areas are the high resistive area. The metal content coefficient enhances structures that have high IP values and low resistivity by normalizing the IP values by the resistivity values. Pseudosection of some of the IP profiles are presented and briefly described below in figures P a g e

Figure 15: Pseudosection Plot of Line 0. The uppermost image is the IP chargeability plot, middle is the resistivity, while the lower section is the metal factor coefficient.

21 Figure 15: Pseudosection Plot of Line 0. The uppermost image is the IP chargeability plot, middle is the resistivity, while the lower section is the metal factor coefficient. The section from west to east has a dipping near-surface high IP chargeability and resistive body from at E along the line. Another high IP zone with relatively low resistivity occurs from E to E, at about 40 m depth; three parallel west dipping high IP and high resistivity zones occur at locations E, E and E about 20m depth.

Figure 16: Pseudosection plot of Line 50S. The uppermost image is the IP chargeability plot, middle is the resistivity, while the lower section is the metal factor co-efficient.

22 Figure 16: Pseudosection plot of Line 50S. The uppermost image is the IP chargeability plot, middle is the resistivity, while the lower section is the metal factor co-efficient. A near surface high IP and resistivity body occurs at the start of the section; two extensive IP anomalies occur at the depth of close to m, locations E and E along the profile. 21 P a g e

Figure 17: Pseudosection plot of Line 150S. The uppermost image is the IP chargeability plot, middle is the resistivity, while the lower section is the metal factor coefficient.

23 Figure 17: Pseudosection plot of Line 150S. The uppermost image is the IP chargeability plot, middle is the resistivity, while the lower section is the metal factor coefficient. Moving from west to east, the section begins with a very low v-shaped resistive zone extending from the near surface to depth, next to it is a very high chargeability and resistive west-dipping zone at location E and 25m depth. 22 P a g e

Figure 18: Pseudosection plot of Line 150N. The uppermost image is the IP chargeability plot, middle is the resistivity, while the lower section is the metal factor coefficient.

24 Figure 18: Pseudosection plot of Line 150N. The uppermost image is the IP chargeability plot, middle is the resistivity, while the lower section is the metal factor coefficient. Moving from east to west, a relatively high resistive and west dipping high chargeability structures occur between E and E. Other deeper high chargeability bodies occur at locations E, and E at depths 60 m and 40 m respectively. 23 P a g e

25 Figure 19: Pseudosection plot of Line 250N. The uppermost image is the IP chargeability plot, middle is the resistivity, while the lower section is the metal factor coefficient. Moving from west to east, the section begins with a high chargeability zone at about m, this has a corresponding low resistive zone. 24 P a g e

26 2. Plan maps False color contour maps of the inverted resistivity and chargeability results are displayed at selected depths. Line data are positioned using UTM coordinates gathered at the survey stations during the field work. This display illustrates the regional distribution of the geophysical trends, outlining strike orientations and possible fault offsets. The plan maps are plotted for both resistivity and chargeability at depth 20 m, 40 m and 60 m. The IP chargeability at about 20 t0 30 m is very broad and irregular in shape. This chargeability at this depth seems to be more related to the clayey silty clay overburden that occurs in most part of the area. They appear as conductive and widely spread with no definite pattern (figures 20 and 21). At a further depth of 50 to 80 m the chargeability and resistivity occur in a definite pattern, mostly trending in the N-S and NNE directions. This is interpreted to be due to high chargeable metals, occurring in disseminated form within a very resistive medium in the project area. The sulfide mineralisations in this region are mostly hosted within the sandstone formation. 25 P a g e

27 Figure 20: Plan map of the IP Chargeability at 20 m depth Figure 21: Plan map of the Resistivity at 20 m depth. 26 P a g e

28 Figure 22: Plan map of the IP Chargeability at 50 m depth Figure 23: Plan map of the Resistivity at 50 m depth 27 P a g e

29 Figure 24: Plan map of the IP Chargeability trend at 80 m depth Figure 25: Plan map of the Resistivity trend at 80 m 28 P a g e

3. 3-D chargeability model The series of parallel 2-D IP pseudosections were further developed into a 3-D voxel model to show the relative continuity of the conductive and chargeable zones

30 3. 3-D chargeability model The series of parallel 2-D IP pseudosections were further developed into a 3-D voxel model to show the relative continuity of the conductive and chargeable zones across the survey area. Fig 26: 3-D voxel model of the IP chargeability effect at about (a) 10 m (b) 50 m. Black arrows show the trend of high IP chargeability at depth of about 50 m. 29 P a g e

5.0 Prospectivity Mapping Figure 29: Prospectivity mapping of EM conductors. Three major conductors were interpreted and labelled 1, 2 and 3. Conductor 3 appears to be multiple linear conductors.

31 5.0 Prospectivity Mapping Figure 29: Prospectivity mapping of EM conductors. Three major conductors were interpreted and labelled 1, 2 and 3. Conductor 3 appears to be multiple linear conductors Figure 30: IP-RES pseudosection plot of Line 0. The interpreted EM conductive structures correspond with high IP chargeability and resistivity bodies along the section 1, 2 and 3. The bodies are dipping north-west at an angle of about degrees. The high resistivity exhibited by this zone could be due to the silicification of the sandstone or high silica content. These bodies could be massive at depth at picked up by the EM data. Conductor 1 appear to occur 30 P a g e

32 near the surface, conductor 2 seems to be faulted, while the broad EM response at conductor 3 is due to multiple dipping conductors as shown on the section. Figure 31: 3-D voxelised northeast trend exhibited by high chargeabilty structure at the peudodepth of about 30 m. 31 P a g e

33 The IP survey further provided more information about the geometry of the EM conductors, as well as the pseudo depth of occurrence. Conductor ID Length (m) Description High and narrow EM response; coincides with magnetic lineament interpreted to be a shallow and NW dipping conductor. High IP chargeability High and narrow EM response; coincides with magnetic lineament interpreted to be shallow and NW dipping conductor. High IP chargeability Broad and low EM response; appears to be three dipping conductive bodies merged; partly within a magnetic lineament corridor; interpreted to be either a deep conductor Total 2780 m 32 P a g e

34 6.0 Conclusion and Recommendation We consider this survey undertaken so far, as very consistent. Interpreted EM conductive bodies occur within the magnetic lineament corridors and have high IP chargeability values. Therefore, we propose target testing via drilling to be carried out on some of the interpreted conductors. Based on the false depth, most of the prospective bodies occur further beyond 30 m depth; therefore, target drilling should be down to 100 m depth. Diamond core drilling method is proposed at five locations along the survey lines as a safety net to increase the confidence level and decrease risks prior to for resource estimation drilling. The core drills aims to basically drill prospecting holes to test the high signature areas from the geophysical investigations to confirm the presence or absence of mineralization and the signature responses associated with the mineralization. It also provides crucial information about the sub-surface to be able to take informed decisions about exploration drilling planning. Criteria considered for the initial target selections include i) occurrence with 500 m of the magnetic lineament corridor, ii) EM anomaly zone based on the FDEM survey, iii) High IP chargeability zone based on the TDIP survey and corresponding high resistivity expected from silicified sandstone or high quartz content rocks. Detailed geochemical sampling of the cores should be undertaken during the test drilling to further characterize the lead-zinc and other mineralisations that occur at the subsurface. 33 P a g e

35 7.0 STATEMENT OF QUALIFICATION Olaniyan Oladele F. - BSc Geology (2002), University of Ado-Ekiti, Nigeria - MSc Geoinformatics (2007), ITC, Netherlands - Ph.D. Exploration Geophysics, Laurentian University, Sudbury, Ontario, Canada. For the past 10 years, I have been actively involved in mineral exploration projects in most part of Nigeria and other parts of the world including Canada, and Ghana. A member of Canadian Exploration Geophysicists Society (KEGS) A member of Council of Nigerian Mining Engineers and Geoscientist (COMEG) A member of Nigerian Mining and Geosciences Society (NMGS) An associate member of the Society of Exploration Geophysicist (SEG) Dated and signed at Sudbury, Ontario, Canada this 10th day of June, Olaniyan Oladele (Ph.D.) 34 P a g e

AND HORSEFLY PROSPECTS, N.W. BRITISH COLUMBIA NTS, 103H/ll, 14 FOR ATNA RESOURCES LTD DELTA GEOSCIENCE LTD

AND HORSEFLY PROSPECTS, N.W. BRITISH COLUMBIA NTS, 103H/ll, 14 FOR ATNA RESOURCES LTD BY DELTA GEOSCIENCE LTD FE T A. HENDRICKSON, P.GEO. 1 . TABLE OF CONTENTS Introduction............. Page 1. Personnel..........