The Lachlan Copper Gold Project (“Lachlan Project”) consist of 13 separate and mostly contiguous tenements and tenement applications over a strike extent of some 160km along the regionally significant Gilmore Suture (Figure 1) in the central Lachlan Orogen of NSW.
- As previously announced to the ASX, Haverford Holdings Ltd (Haverford), a 100% owned subsidiary of Talisman, has entered into a Farm-In Agreement (Farm-in) with Bacchus Resources Pty Ltd (Bacchus) over certain Lachlan Cu-Au Project tenements.
In accordance with the terms of the Farm-in:
- Haverford can earn up to a 80% interest in the Bacchus Tenements (EL8547, EL8571, EL8638, EL8657, EL8658 and EL8680) by sole funding $2.3M of on-ground exploration expenditure over four years; and
- Should Haverford earn an interest in the Bacchus Tenements, Bacchus is entitled to receive a 20% interest in the Haverford Tenements (EL8615, EL8659 and EL8677). Should Haverford not earn an interest in the Bacchus Tenements, Bacchus may elect to take a 20% interest in the Haverford Tenements.
- As previously announced to the ASX, Haverford has entered into a Farm-In Agreement (Farm-in) with Peel Mining Limited (ASX:PEX) over PEX’s Mt Walton (EL8414) and Michelago (EL8451) Projects (collectively the Peel Tenements). In accordance with the terms of the Farm-in, Haverford can earn up to a 75% interest in the Peel Tenements by sole funding $0.7M of on-ground exploration expenditure over five years.
The Project covers a package of volcanic and sedimentary rocks that are highly prospective for copper-gold and base metal mineralisation associated with major structures (“Cobar Style”); Volcanic Associated Massive Sulphide (“VAMS”) base metal deposits; and high and intermediate sulphidation epithermal gold deposits.
The Cambelego-Mineral Rift sequence host a number of high-grade deposits including the Mt Boppy Gold deposit, the historic Bobadah, Blind Calf and Babinda copper-gold mines; and the Mineral Hill copper and base metal mine. Small scale mining of copper, gold and base metals has occurred throughout Talisman’s Lachlan Project, as evidenced by the many historic mine shafts (Figure 2).
Historic exploration data for the area comprises sporadic isolated surface sampling (soil, rock-chip and auger samples), and limited RC and diamond drilling. The majority of this work was completed by a number of explorers throughout the 1970’s, 1980’s and early 1990’s, with some of the most recent work completed in 2010 and 2011. Talisman’s review of the data has highlighted that there has been no coordinated, systematic regional exploration across the tenement package, which until now has been fragmented and under the control of multiple exploration companies.
Talisman is undertaking a staged systematic exploration approach across the Lachlan Project area which is designed to build a pipeline of exploration targets through rigorous and sound exploration techniques.
This approach has three integrated stages of work:
Stage 1: Reconnaissance Exploration
Stage 1 work includes the identification of geological target areas through the interpretation of base layer regional data sets including geophysical data, geological mapping, the collation and interpretation of historic data, and on-ground prospecting by Talisman’s geological team.
Following this work, systematic geochemical data is collected across areas identified as conceptual targets and may include auger drilling or conventional soil sampling, depending on target area ground conditions. More localised geophysical surveys including surface EM, gravity or IP surveys may also be undertaken at this stage.
The Lachlan Project covers over 3,200km2 of the highly prospective Cambellego-Mineral Hill Rift sequence. As currently proposed, Stage 1 reconnaissance exploration across the Lachlan Project area is anticipated to continue for the next 12 – 18 months in parallel with the drilling of more advanced targets.
The first Stage 1 geochemical sampling programs completed to date by Talisman on the Central Lachlan Project Area have identified two separate geochemical anomalies that will be advanced to Stage 2, including a large base metal anomaly in the Central region of the Lachlan Project area (EL8615 - Myamley Project), associated with north-east trending fault structures identified by TLM during preliminary reconnaissance prospecting (Figure 3). It is anticipated that more such anomalies will be generated over the next 6 – 12 months as Talisman’s geochemical sampling crew continue to collect high-quality data.
Figure 3:EL8615 - Myamley Project - Auger geochemistry
This Stage 1 work is ongoing, with the auger drill rig testing the south-eastern extensions of the Mineral Hill and Blind Calf mineralisation corridors (Figure 4).
Figure 4: Lachlan Project Area – Southern Region, showing on-going Stage 1 auger sampling areas, planned Stage 3 RC drilling areas and historic rock-chip results
Stage 2: Target Development
Following on from the initial geochemical data collection and interpretation, anomalous areas are assessed based on geology, regolith and geomorphology criteria. Anomalies that are assessed as favourable are advanced though to Stage 2 testing. This second stage work may include deeper air-core and/or RC drilling depending on a number of geological factors including depth of cover and weathering.
The NSW Department of Energy and Resources (DER) has defined a clear process for the application and granting of work programs. This process involves several steps, including specific on-ground data collection prior to the submission of an application, and statutory notice periods following DER approval of the submitted work program. From the date of submission of a work program with the DER, on-ground Stage 2 activity generally commences six weeks later.
Talisman currently has two work programs for Stage 2 drilling lodged with the DER including RC drilling to test the historic Cumbine (IP and geochemical) anomaly and the Cu-Pb-Zn geochemical anomaly identified in Talisman’s first auger sampling program (refer to TLM ASX release dated 17 May 2018).
Given the lag in timing from target identification through to on-ground activity, it is prudent for Talisman to have a series of work programs at various stages progressing through the DER in parallel. Accordingly, in addition to the two work programs currently being assessed by the DER, Talisman has a further two work programs in draft which are anticipated to be submitted for DER assessment in the coming weeks.
Stage 3: Refined Targeting
The final stage of Talisman’s exploration strategy is refined targeting. This work includes follow-up RC and diamond drilling of Stage 2 targets, DHEM surveys and detailed structural logging and analysis of drill core.
Talisman is currently progressing one Stage 3 work program, which will include both RC and diamond drilling to follow-up the high-grade copper mineralisation identified at the Blind Calf Prospect identified in the recently completed Stage 2 RC drilling campaign (Figure 5 & Figure 6). This Stage 3 exploration at Blind Calf is anticipated to be on-going with new work programs submitted following successful completion of the previous drilling and interpretation of results.
Figure 5: Blind Calf long section showing historic drilling, and recent high-grade Intersections from Talisman drilling.
Figure 6: Blind Calf Prospect - Drill collar location plan
This work is again subject to the estimated six-week approval period between work program submission and the commencement of on-ground activity. While Talisman currently has one prospect area in the Stage 3 category of exploration, in the fullness of time it is anticipated that many more target areas will be elevated to advanced exploration status.
Talisman, in association with specialists Consultants, has undertaken a regional structural and geological interpretation of the area as part of its first pass exploration work. This work included a detailed geological review of the known major mineral deposits in the district which has provided valuable insight to the major regional controls on mineralisation.
The nature of the cover, lithology and mineralisation styles within the Lachlan Project area means geophysical targeting techniques such as EM, IP and gravity surveying are effective tools in defining drill targets.
Talisman intends to build a strong database of soil sampling, auger sampling, geological and structural mapping and geophysical surveys to develop and prioritise targets for drilling.
As a result of the work undertaken to date, Talisman has highlighted several high priority areas within the wider Southern Region Project Area (Figure 1), for initial focus where more detailed geological interpretations have been completed or are underway.
Talisman has continued to work closely with the relevant local landholders to secure access across its tenure. Talisman’s culture of inclusive communication and engagement with all stakeholders has seen it establish a strong community licence to operate in the area, while securing access to all of the currently identified high priority areas.
Talisman will continue to build a regional data set including geochemical, geophysical and geological data, to enhance the understanding of the regional and localised control on mineralisation. In conjunction with this regional prospect generative work, Talisman will continue to test the highest priority targets as they become apparent with RC and/ or diamond drilling, detailed surface and down-hole geophysical surveys.