Exploration and Development
The Company’s proposed strategy for the Gum Creek Gold Project comprises three key objectives:
- undertake extensional and infill drilling to grow the known resources and lift defined resources into higher-confidence JORC categories;
- undertake regional exploration targeting new gold discoveries outside of the known resources; and
- carry out development studies (including but not limited to metallurgical and processing investigations) on the free milling and refractory mineralisation.
The initial phase of the FY2018 reverse circulation (RC) drilling program nearing completion – 39 drill-holes completed for 4,969 drill metres at 13 prospects. Positive results from Psi, Toedter, Ray Charles and Shiraz South, including:
- 7m @ 4.94g/t Au from 55m in GWRC462 (Psi – reported previously)
- 1m @ 20.6g/t Au from 133m in GWRC482 (Toedter)
- 1m @ 2.53g/t Au from 83m in GWRC439 (Ray Charles)
- 1m @ 2.40g/t Au from 138m in GWRC429 (Shiraz South)
The initial phase of the FY2018 aircore (AC) drilling program is almost complete – 440 drill-holes completed for 20,118 drill metres at eight prospects. Better intersections include:
- 4m @ 2.84g/t Au from 28m in GPAC1261 (Gidgee South)
- 4m @ 3.38g/t Au from 76m in GPAC0922 (Melbourne Bitter)
- 4m @ 2.21g/t Au from 72m in GPAC1057 (Orion)
Ten 10 RC drill-holes planned at Ray Charles, Howards, Big West and Rail and 92 AC drill-holes proposed for Wahoo East, which will complete the initial FY2018 RC and AC drilling programs;
The initial FY2018 drill results warrant follow-up drill testing at several prospect areas, with priority targets at Psi and Toedter; and
A comprehensive review of the Gum Creek geochemical data base is underway.
In the September 2017 Quarterly Activities Report, the Company advised that it had completed the initial phase of exploration on the 14 regional priority targets listed in the Company’s IPO Prospectus (October 2016). The Company also advised that it had commenced, in August 2017, follow-up drill testing on 20 new prospect areas generated as a result of the initial phase of exploration (Figure 1). The follow-up drill programs, using a combination of reverse circulation (RC) and aircore (AC) drilling methods, are expected to be completed early in 2018. The majority of assay results from the drilling programs completed to date have now been received by the Company and are presented in this release.
Figure 1 Colour gravity image showing twenty prospect target areas
Reverse Circulation (RC) Drilling Program
RC Drilling – Progress
During the September 2017 Quarter, the Company reported on 27 reverse circulation (RC) drill-holes at 10 prospects areas.
Since then and prior to a scheduled break in the RC drill program in November 2017, a further six RC drill-holes were completed. Drilling resumed in early December 2017, and an additional six RC drill-holes were completed at Wilsons South prior to a mechanical failure of the rig’s compressor system, which has delayed completion of the program until a replacement drill rig can be sourced in early January 2018. Ten RC holes at Ray Charles, Howards, Big West and Rail remain to be drilled to complete the initial FY2018 RC drilling program.
For the program to date, a total of 39 drill-holes for 4,969 drill metres have been completed at 13 prospects. Drill-hole locations are shown in Figure 1 (hole co-ordinates are reported in Table 1, Appendix 1 of the ASX Announcement 21 Dec 17).
RC Drilling – Assay Results
As at the date of the September 2017 Quarterly Report, the Company had reported assay results for 19 of the 27 holes completed at that time. Final assay results (based on 1m RC assay split samples) for 33 drill-holes have now been received and are reported in Table 1, Appendix 1. Initial composite 4m assay samples for the six RC holes completed in December 2017 are currently being analysed, with final assay results expected to be reported in the Company’s December 2017 Quarterly Activities Report.
All gold (Au) results in Table 1 are based on 30gm fire assays reported to a 1.0g/t Au lower cut-off grade. The 2012 JORC Compliance Tables to accompany these results are contained in Appendix 2.
The most encouraging assay results from the RC drill program were at Psi where fourteen drill-holes for 1,369 drill metres were completed (refer Figure 2 and Figure 3). The better intersections, which were previously reported in the September 2017 Quarterly Activities Report, included:
- 7m @ 4.94g/t Au from 55m in GWRC462;
- 6m @ 4.16g/t Au from 80m in GWRC464;
- 5m @ 4.15g/t Au from 68m in GWRC466;
- 5m @ 3.60g/t Au from 62m in GWRC467; and
- 4m @ 5.34g/t Au from 56m in GWRC469.
Other encouraging results returned were at Toedter, Ray Charles and Shiraz South.
At Toedter (Figure 2), a single RC drill-hole (GWRC482) targeting a coincident de-magnetised BIF and electromagnetic (EM) conductor, returned 1m @ 20.6g/t Au from 133m. The target tested by GWRC482 is one of five coincident BIF – EM targets associated with a 6km long, mostly buried BIF unit located to the west of the main Toedter prospect area.
At Ray Charles (Figure 2), one of three RC holes (TTRC439) drilled to target a series of Induced Polarisation (IP), EM and surface geochemical targets returned 1m @ 1.68g/t Au from 79m and 1m @ 2.53g/t Au from 83m. Four other planned RC holes at Ray Charles, in the vicinity of TTRC439, remain to be drilled early in 2018.
At Shiraz South (Figure 2), a single RC hole (TTRC429) drilled to target an IP anomaly located at depth immediately south of Shiraz, returned a final intercept of 1m @ 2.40g/t Au from 138m.
RC Drilling – Next Steps
The immediate focus for the March 2018 quarter will be to complete the remaining 10 planned RC drill-holes at Ray Charles, Howards, Big West and Rail in the initial phase of the FY2018 RC program.
Follow-up RC drilling is planned at Psi and Toedter. At Psi, an additional eight RC drill-holes are planned to test the shallow, south plunging banded iron formation (BIF) hosted mineralisation (Figure 3). The mineralised grades and thicknesses intersected at Psi are consistent with historical drilling intercepts and confirm the mineralisation is mostly confined to a single sheared structure with higher-grade lenses plunging more shallowly to the south than previously thought.
At Toedter, a combination of AC and RC drilling is planned to follow-up the high-grade intersection in drill-hole GWRC482, and test five other coincident de-magnetised BIF and EM conductors identified along a 6km long, mostly buried BIF unit located to the west of the main Toedter prospect area.
Aircore (AC) Drilling Program
AC Drilling – Progress
The aircore (AC) drilling phase of the 2017 Gum Creek drill program targeted a series geochemical, geophysical and structural targets identified at a number of prospects, including Gidgee South, Howards, Kurrajong, Melbourne Bitter, Orion, Ray Charles, Wahoo West and Wilsons (Figure 1).
Between September and November 2017, a total of 440 AC drill-holes were completed for 20,118 drill metres at eight prospects. Drill-hole locations are shown in Figure 1, and hole co-ordinates are reported in Table 2, Appendix 1.
AC Drilling – Assay Results
Various AC intercepts were returned from Gidgee South, Melbourne Bitter and Orion prospects (Figure 2). The anomalous Gidgee South AC results were at the Sprocket, Brifter and Ferrule prospect areas (Figure 4). Best intersections returned from the AC drill program include:
- 4m @ 0.69g/t Au from 80m in GPAC1094 (Gidgee South);
- 4m @ 0.68g/t Au from 0m in GPAC1231 (Gidgee South);
- 5m @ 0.92g/t Au from 28m in GPAC1235 (Gidgee South);
- 4m @ 0.52g/t Au from 32m in GPAC1259 (Gidgee South);
- 4m @ 2.84g/t Au from 28m in GPAC1261 (Gidgee South);
- 4m @ 0.83g/t Au from 24m in GPAC1282 (Gidgee South);
- 4m @ 0.61g/t Au from 32m in GPAC1283 (Gidgee South);
- 4m @ 1.62g/t Au from 96m in GPAC0907 (Melbourne Bitter);
- 4m @ 1.32g/t Au from 0m in GPAC0921 (Melbourne Bitter);
- 4m @ 3.38g/t Au from 76m in GPAC0922 (Melbourne Bitter);
- 4m @ 0.77g/t Au from 76m in GPAC0931 (Melbourne Bitter);
- 4m @ 0.83g/t Au from 32m in GPAC1043 (Orion);
- 4m @ 1.00g/t Au from 60m in GPAC1051 (Orion); and
- 4m @ 2.21g/t Au from 72m in GPAC1057 (Orion).
No anomalous results were returned from the Ray Charles, Wahoo West, Howards and Wilsons prospect areas.
Table 2 in Appendix 1 lists the drill results for all the completed AC drill holes and Appendix 2 contains the appropriate 2012 JORC Compliance Tables to accompany these results. All gold (Au) results reported in Table 2 are based on 30gm Fire Assays reported to a 0.5g/t Au lower cut-off grade, using 4m composited samples.
AC Drilling – Next Steps
Initial AC drilling is planned at Wahoo East (92 holes).
Follow-up AC drilling, to better define the anomalous results returned from the initial FY2018 AC drilling program, is planned at Toedter, Gidgee South, Melbourne Bitter and Orion.
The Company holds an extensive geochemical database for the Gum Creek project, comprising over 81,000 surface samples and 70,000 drill holes. During the December 2017 quarter, Horizon engaged GCXplore Pty Ltd to undertake a comprehensive review of the Gum Creek geochemical database with the aim of generating new drill targets and to assist in the planning for new exploration activities.
The work by GCXplore is well advanced, with several targets identified for drill testing in 2018. Further details on the work and targets is detailed in the December 2017 Quarterly Report.