DISTRICT TO CAMP SCALE GEOCHEMICAL SIGNATURES AND ZONING OF INTRUSION RELATED MINERAL SYSTEMS, CHARTERS TOWERS PROVINCE

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1 DISTRICT TO CAMP SCALE GEOCHEMICAL SIGNATURES AND ZONING OF INTRUSION RELATED MINERAL SYSTEMS, CHARTERS TOWERS PROVINCE CHARACTERIZATION OF INTRUSION-RELATED HYDROTHERMAL MINERAL SYSTEMS IN THE CHARTERS TOWERS REGION, NORTHEAST QUEENSLAND Dr Simon Beams, Principal Geologist Terra Search Dr Gregg Morrison, Principal, Klondike Exploration Services A component of the Queensland Government Future Resources Program -Industry Priorities Initiative- We Acknowledge Industry Support by Industry Partners : Resolute Mining Limited; Piccadilly Gold Mines

2 Charters Towers Block Start of Project June ,000 seds (blue) 132,000 soils (red) 31,000 rock chip (green) 11,000 drill holes (black) Min Occ (gold) May 2015 Data set to manipulate has grown to 181,000 soils 42,000 rock chip 16,600 drill holes

3 Charters Towers Regional Cu in Rockchips

4 Charters Towers Regional Cu in Soils

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6 Charters Towers Regional Au in Soils

7 Charters Towers 8157 Mo in Rock Chips

8 Ravenswood 8257 Mo in Rock Chips

9 Ravenswood 8257 Bi in Rock Chips

10 PICCADILLY EXAMPLE of CAMP SCALE ZONING AND GEOPHYSICAL SIGNATURE Exploration Permits Mining Leases The Piccadilly Project is located approximately 80kms WSW of Townsville and 50kms NW of Charters Towers, North Queensland PICCADILLY GOLD MINES 20 Kms August 2014

11 Piccadilly : A deep magnetic low magnetic reversal RTP Aeromagnetic Image re-stretched for the area. Circular feature suggests blind intrusion.

12 Piccadilly : Analytical Signal Ground magnetic Image Independent of field direction. Interpreted Centre of intrusion

13 GEOCHEMISTRY Soil geochemistry depicts the Zinc - Copper enriched zone overlapping with a broad distal Lead zone. The Lead enriched zone extends up to ~3km from the core of the system. Zn Cu Mo (W, Bi*) Pb 1 Km PICCADILLY GOLD MINES February, 2015

14 Piccadilly Geochemical zonation overlain on ground magnetic Analytical signal image. Interpreted intrusive centre, dacitic to rhyolitic dykes.

15 Multi-metal data interpretation Select metals & sort (use ½ detection to eliminate negative values) Define populations by rock type or favoured metal and calculate an average Select background type e.g. granite from Wedepohl table and normalise the population. List relative enrichment in orders of magnitude Compare with reference chart to define system type For detailed zoning do Z-score & PCA analysis & IOGAS display on assemblages of metals in thematic map or cross-section. KLONDIKE

16 Typical dataset rock chip, n=238, no data Ba Sn W average granod enrich Ag As Au Ba Bi Cu Mo Pb Sb Sn Te W Zn Au Ag Pb Bi(As Cu) +/-Te Zn Table of averages for each element divided by values for typical granodiorite to get enrichment. Elements listed in bold represent the relative order of enrichment for this suite. Au with Ag Pb Bi indicates a magmatic system with moderate fractionation. Strong fractionation would have richer base metals. Bi +/- Te rich suggests an intermediate intrusive source like tonalite-granodiorite Ag-Pb-As imply distal zone is being sampled at surface. Overall this sample suite could represent a mafic magmatic hydrothermal system emplaced at porphyry level. This is consistent with known geology & presence of euhedral buck quartz veins and granitic vein dikes. KLONDIKE

17 IRGS NQ Classification using multi-metal data Based on 13 metal set Au Ag As Sb Pb Zn Cu Bi Te Mo W Sn Normalised to host or related intrusion Classified in terms of relative enrichment Scheme based on ~100 examples from Charters Towers region Our example Au Ag Pb Bi(As Cu) +/- Te Zn Fits the Au-Bi-BM+/-Te porphyry Au type c.f. Mt Leyshon CLASSIFICATION SCHEME AU+BM (NO BI +/-AS, TE) OROGENIC GRANITE-HOSTED TYPE e.g. Charters Towers AU BI TE AS SB (+/-BM) AU-BI-BM +/-TE AU BI MO W +/- BM AU AG TE AU AG AS AU AG TE AS +/- BM PLUTONIC IRGS TYPE and or mafic intrusion e.g. Ravenswood PORPHYRY AU TYPE and or intermediate intrusion e.g. Mt Leyshon, Mt Wright CU RICH ZN-RICH PB-RICH PORPHYRY AU TYPE with felsic intrusion e.g. Mt Remarkable, Kidston LOW SULFIDATION EPITHERMAL VEINS e.g. Pajingo EPITHERMAL HOTSPRING DEPOSITS e.g. Wirralie HI-SULFIDATION EPITHERMAL e.g. Mt Carlton KLONDIKE

18 MM data interpretation: metal zoning model With two or three dimensional data sets and a few hundred data points It is possible to build a metal zoning model Do Z-score(standard deviation) test on each element to make all elements equal Plot the Z-scores in plan or section and manually look for spatial overlap of metal concentrations Combine and average Z-scores for multiple elements to define zones Or do a principal component analysis on the Z-scores to define element clusters Contour zones KLONDIKE

19 Ravenswood District: Three Sisters metal zoning KLONDIKE

20 KIDSTON Pipe Metal Zoning Confined in pipe Overall zoning on a Thermal gradient Au only above sill With Pb-Zn-Cu Deep Mo-W-Bi Classify: IGMX Exposed distal BM Core Mo-W- Bi KLONDIKE

21 IRGS NQ Mt Wright soil and rock metal zoning Zn-Ag-Pb Pb-Zn 3km diameter soil anomaly Zn, Bi, Au only 5ppb on hill 1km tall system, well zoned Au 0.1ppm at surface, Best Au ore m below KLONDIKE

22 Complete classification of porphyry hydrothermal systems CLASSIFICATION & ZONING PATTERNS FOR PORPHYRY-RELATED HYDROTHERMAL SYSTEMS METAL ASSOCIATION CLASSIFICATION Au Cu-Au Cu-Mo Mo-W-Bi Sn-W Sn-B EXAMPLE Eastern Australia Fifield Goonumbla Mount Leyshon Kidston Herberton Cooktown EXAMPLE World Maricunga Chile British Columbia Bingham Climax Erzgebirge NE Tasmania IGNEOUS CHARACTERISTICS CHEMICAL TYPE; FRACTIONATION; REDOX M, U-F, O M, U-F, SO-O I, U-F, O I, F, O-R I, F, R S, F, R IGNEOUS ROCK TYPE ON QAP DI-QD-TN DI-MZD-MZ-QMZ DI-GD-MZG QMZ-MZG-SYG MZG-SYG-AFG SYG-QSY-ASY METAL ZONING MARGINAL DISTAL (As) DISTAL (BM) PROXIMAL (BM) CORE Hg, S Ca Ca F, U F, Ba, Se, Hg, U F As (Au) Au As Sb (As, Sb, Au) (As Ag Sb Au) As (Au) As Pb, Zn, Ag, Sb, (Au) Pb Zn Ag Au (Cu Mo Te) Pb Zn Ag (Au, Bi) Zn Cu Pb Bi Au Pb Ag Zn Zn Pb Ag Au Cu Mo (Ag, As) Cu (Zn) Cu Au Ag (Bi Te) Cu (Au Bi Te) Cu Mo Bi Cu Bi Mo (W) Au, Te, (Pt) Cu Au (Te) Cu Mo W Mo Bi Sn W Sn B (W) Klondike Exploration: AMIRA P425, July 1997 Combining the igneous classification and the zoning pattern we can work back and forth between when there is limited information. With multi-element data we can interpret the most likely position in system based on the most enriched elements relative to background. And define the system type based on key elements like Te, Bi, Mo, Sn N.B. different position for Au concentration(shaded) distal/felsic KLONDIKE

23 MM data interpretation: Metal Zoning in IRGS model Overall metal association distinguishes crustal levels of systems As-Sb typical epithermal Basemetals typical porphyry level Bi-Te without basemetals plutonic KLONDIKE