LIST OF FIGURES APPENDICES

Transcription

1 RESISTIVITY / INDUCED POLARIZATION SURVEY EL PORVENIR PROJECT MUNICIPALITY OF REMEDIOS, ANTIOQUIA, COLOMBIA LOGISTICS REPORT M APRIL 2017

2 TABLE OF CONTENTS Abstract The Mandate El Porvenir Project Resistivity / Induced Polarization Survey Results Conclusions and reccommendations LIST OF FIGURES Figure 1. General location of El Porvenir Project... 2 Figure 2.Survey grid of El Porvenir Project... 4 Figure 3. Pole-dipole electrode arrangements... 5 Figure 4. Principle of the Induced Polarization (I.P.) method... 6 Figure 5. Principle of data acquisition of the Multi-electrodes Resistivity and IP method... 8 Figure 6. Resistivity ranges of selected soils and rocks... 8 APPENDICES A. Resistivity and chargeability sections - Iguanacito B. Resistivity and chargeability sections - Guayabales C. Resistivity and chargeability sections - Abejero D. Ground Magnetic maps - Iguanacito E. Ground Magnetic maps - Guayabales F. Ground Magnetic profile - Abejero G. Depth slice - Iguanacito H. Depth slice - Guayabales A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE I

3 ABSTRACT On behalf of Angel Gold Corporation, a geophysical campaign was carried out by KTTM Geophysics over El Porvenir Project located within the municipality of Remedios, Antioquia, Colombia. The objective of this campaign was to assess the potential for gold mineralization. From February 24 th to Match 27 th, 2017, a total of line-km of induced polarization (IP) surveying (pole-dipole; a = 50 m, n = 1 to 10) and line-km of ground magnetic surveying was carried out over Iguanacito prospect (13.75 linekm),guayabales Prospect (6.7 linekm) and Abejero Prospect (1.4 linekm). Processing of all geophysical data were all successfully performed by Geophysics GPR International Inc. A N G E L GOL D CO R P. E L P O R V E N I R PR O J E C T / M PAGE 1

4 1. THE MANDATE PROJECT ID El Porvenir Project (Our reference: M-17427) GENERAL LOCATION Municipality of Remedios, Antioquia, Colombia COMPANY Angel Gold Corp. REPRESENTATIVE Mr. Jim Stephenson Vice President of Exploration Tel: +57 (4) SURVEY TYPES GEOPHYSICAL OBJECTIVE Time domain resistivity / induced polarization (pole-dipole array). Ground Magnetic Survey. To assess the potential for gold mineralization. Figure 1. General location of the El Porvenir Project A N G E L GOL D CO R P. E L P O R V E N I R PR O J E C T / M PAGE 2

5 2. EL PORVENIR PROJECT COORDINATE SYSTEM Projection: Universal Transverse Mercator, zone: 18N Datum: WGS 84 GEOMORPHOLOGY The Project is situated within the Segovia gold belt, the most prolific gold belt in Colombia from which gold has been exploited for 150+ years. Two north / south trending faults conveniently divide the Project geology. Precambrian age gneisses are present east of the Bagre fault, Cretaceous age Sedimentary and volcanic rock units lie between the Bagre and Nus faults and granodiorite rocks of the Segovia batholith lie west of the Nus fault. The gold deposits of Gran Colombia s Segovia project are hosted by the Segovia batholith. Gold mineralization in the area is believed to be related to the emplacement of the Segovia batholith and the Otu fault located about 7 km west of the El Porvenir project MINING LAND TENURE Option agreement to acquire a 100% interest from MINEROS S.A. SURVEY GRIDS Iguanacito Prospect: The grid is composed of 13 NW-SE lines, with a length of 1 km to 1.25 km per line. Guayabales Prospect: The grid is composed of 5 SW-NE lines, with a length of 1 km to 1.6 km per line. Abejero Prospect: The prospect is composed of one NW-SE line, with a length of 1.4 Km per line. A N G E L GOL D CO R P. E L P O R V E N I R PR O J E C T / M PAGE 3

6 Iguanacito Prospect Guayabales Prospect Survey line at Abejero Prospect Figure 2. Survey grid of El Porvenir Project A N G E L GOL D CO R P. E L P O R V E N I R PR O J E C T / M PAGE 4

7 3. RESISTIVITY / INDUCED POLARIZATION SURVEY TYPE OF SURVEY Time domain resistivity / induced polarization Pole-dipole array: "a" = 50 m, "n" = 1 to 10 Figure 3. Pole-dipole electrode arrangements SURVEY COVERAGE DATA ACQUISITION line-km of IP and line-km of ground magnetic. The IP/EI data were collected using an IRIS Instrument Syscal Pro multi-electrodes receiver and a GDD 5000 Watt's transmitter as a source. A Pole-Dipole configuration was used for the survey. Non-polarizable stainless steel electrodes were used for data acquisition. Ten consecutive time windows, over which the signal is measured after the applied voltage is cut-off, were used to record the data To derive a model of the subsurface that satisfied both the measured resistivities and chargeabilities, the IP data were inverted along with the EI data using the Res2Dinv software from Geotomo written by Dr. Loke that uses the smoothnessconstrained least-squares inversion technique (Loke et al. 2003). Geosoft was used to generate the final profile and depth slice images. A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 5

8 IP METHOD The IP method focuses on the decaying potential difference as a function of time for portions of the earth where current flow is maintained for a short time after the applied voltage is cut off. In common rocks, the current that flows under the action of an applied voltage does so by ionic conduction in the electrolyte in the pores of the rock and drops instantaneously to zero after the current is turned off. For certain minerals, however, there is also a detectable electronic conduction that only decays to zero after a given interval of time. Time-domain IP was used for this survey and chargeability, defined as the ratio of the area under the decay curve to the potential difference measured before switching off the current, was measured. Figure 4 illustrates the principle of the Induced Polarization method. Figure 4. Principle of the Induced Polarization (I.P.) method A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 6

9 ELECTRICAL IMAGING METHOD The purpose of electrical surveys is to determine the subsurface resistivity distribution by making measurements on the ground surface. The ground resistivity is related to various geological and physical parameters such as the mineral and fluid content, porosity and degree of water saturation in the rock. The resistivity measurements are normally acquired by injecting current into the ground through two current electrodes (C1 and C2 in Figure 3) and measuring the resulting voltage difference at two potential electrodes (P1 and P2). From the current (I) and voltage (V) values, an apparent resistivity (ρa) value is calculated. Resistivity values are generally expressed as ohm-metres (ohmm). The calculated resistivity value is not the true resistivity of the subsurface, but an "apparent" value that is the resistivity of a homogeneous ground, which will give the same resistance value for the same electrode arrangement. The relationship between the "apparent" resistivity and the "model" resistivity is a complex relationship. To determine the subsurface resistivity, an inversion of the measured apparent resistivity values using a computer program must be carried out. Resistivity surveys give a picture of the subsurface resistivity distribution. To convert the resistivity picture into a geological picture, some knowledge of typical resistivity values for different types of subsurface materials and the geology of the area surveyed is important. Figure 4 gives the resistivity values of common rock, soil materials and chemicals. The resistivity of these rocks is greatly dependent on the degree of fracturing, and the percentage of the fractures filled with ground water. The interpretation of resistivity data consists of a geophysical inversion by which we seek to find a model that gives a response that is similar to the actual measured values. The model is an idealized mathematical representation of a section of the earth. It is based on a set of model parameters that are the physical quantities we want to estimate from the observed data. The problem of non-uniqueness is well known in the inversion of resistivity sounding and other geophysical data. For the same measured data set, there is wide range of models giving rise to the same calculated apparent resistivity values. To narrow the range of possible models, some assumptions are made concerning the nature of the subsurface that can be incorporated into the inversion subroutine. A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 7

10 FIGURE 5: Principle of data acquisition of the Multielectrodes Resistivity and IP method Figure 6: Resistivity ranges of selected soils and rocks A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 8

11 4. RESULTS The results are presented in the appendix as profiles. On all sections given in the appendix, we have kept the horizontal and vertical scale and color bar consistent. We have also generated a pseudo 3D cube from the Resistivity/IP data and created depth slices at a constant elevation of respectively 250 meters, 300 meters, 400 meters and 500 meters for Guayabales prospect and also a constant elevation of respectively 595 meters, 620 meters, 645 meters and 670 meters for Iguanacito prospect; which we feel are representative of the geology. At this stage, we can only make general comments on the results to guide the interpretation based on the limited geological information we had at the time of the report preparation. This interpretation should be reviewed with the existing drilling, geochemical data, known regional geology and surface geological mapping. A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 9

12 5. CONCLUSIONS AND RECOMMENDATIONS The data was overall of good quality and the inversion process yielded an acceptable RMS error between the model and the measured sections (error between 1 and 4% for the IP) for all prospects. Near surface variations yielded higher RMS errors for the resistivity sections (average of 10%). The chargeability reach anomalous values in the range of 2 to 20 mv/v and higher, while resistivity values vary between 20 and 4000 Ohm-m. It is recommended that an integration of geological, geotechnical and possibly drill holes data with the results of this geophysical survey be done. Respectfully submitted, Geophysics GPR International Inc. KTTM Geophysics Claude Robillard, P.geo.geoph. OGQ # 297 Senior Geophysicist Mahdi Brakni, P.geo.geoph. OGQ # 1781 Geophysicist Project Manager A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 10

13 APPENDIX A RESISTIVITY & CHARGEABILITY SECTIONS IGUANACITO PROSPECT A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 11

14 Line NW section A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 12

15 Line NW A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 13

16 Line 8+00 NW A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 14

17 Line 6+00 NW A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 15

18 Line 4+00 NW A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 16

19 Line 2+00 NW A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 17

20 Line 1+00 NW A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 18

21 Line 0+00 SE A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 19

22 Line 1+00 SE A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 20

23 Line 2+00 SE A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 21

24 Line 3+00 SE A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 22

25 Line 4+00 SE A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 23

26 APPENDIX B RESISTIVITY & CHARGEABILITY SECTIONS GUATABALES PROSPECT A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 24

27 Line 6+00 SW A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 25

28 Line 4+00 SW A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 26

29 Line 2+00 SW A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 27

30 Line 0+00 NE A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 28

31 Line 2+00 NE A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 29

32 APPENDIX C RESISTIVITY & CHARGEABILITY SECTIONS ABEJERO PROSPECT A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 30

33 Line 0+00 NW A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 31

34 APPENDIX D GROUND MAGNETIC MAPS IGUANACITO PROSPECT A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 32

35 Analytical Signal A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 33

36 Reduction to the Equator A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 34

37 Reduction to the Pole A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 35

38 Total Field Intensity A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 36

39 Vertical First Derivative A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 37

40 APPENDIX E GROUND MAGNETIC MAPS GUAYABALES PROSPECT A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 38

41 Analytical Signal A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 39

42 Reduction to the Equator A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 40

43 Reduction to the Pole A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 41

44 Total Field Intensity A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 42

45 First Vertical Derivative A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 43

46 APPENDIX F GROUND MAGNETIC PROFILE ABEJERO PROSPECT A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 44

47 A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 45

48 APPENDIX G IGUANACITO DEPTH SLICE AT ELEVATION = 595 m DEPTH SLICE AT ELEVATION = 620 m DEPTH SLICE AT ELEVATION = 645 m DEPTH SLICE AT ELEVATION = 670 m A N G E L GOL D CO R P. E L P O R V E N I R P R O J E C T / M PAGE 46

49 Induced Polarisation Resistivity DEPTH SLICE AT ELAVATION = 595 m A N G E L GOL D CO R P. E L P O R V E N I R PR O J E C T / M PAGE 47

50 Induced Polarisation Resistivity DEPTH SLICE AT ELAVATION = 620 m A N G E L GOL D CO R P. E L P O R V E N I R PR O J E C T / M PAGE 48

51 Induced Polarisation Resistivity DEPTH SLICE AT ELAVATION = 645 m A N G E L GOL D CO R P. E L P O R V E N I R PR O J E C T / M PAGE 49

52 Induced Polarisation Resistivity DEPTH SLICE AT ELAVATION = 670 m A N G E L GOL D CO R P. E L P O R V E N I R PR O J E C T / M PAGE 50

53 APPENDIX H GUAYABALES DEPTH SLICE AT ELEVATION = 250 m DEPTH SLICE AT ELEVATION = 300 m DEPTH SLICE AT ELEVATION = 400 m DEPTH SLICE AT ELEVATION = 500 m A N G E L GOL D CO R P. E L P O R V E N I R PR O J E C T / M PAGE 51

54 Induced Polarisation Resistivity DEPTH SLICE AT ELAVATION = 250 m A N G E L GOL D CO R P. E L P O R V E N I R PR O J E C T / M PAGE 52

55 Induced Polarisation Resistivity DEPTH SLICE AT ELAVATION = 300 m A N G E L GOL D CO R P. E L P O R V E N I R PR O J E C T / M PAGE 53

56 Induced Polarisation Resistivity DEPTH SLICE AT ELAVATION = 400 m IAMGOLD C O R P O R A T I O N. C A R AM A N T A PR O J E C T / M PAGE 54

57 Induced Polarisation Resistivity DEPTH SLICE AT ELAVATION = 500 m IAMGOLD C O R P O R A T I O N. C A R AM A N T A PR O J E C T / M PAGE 55