AUSTRALIAN base metals explorer Ventnor Resources has significantly boosted its portfolio after acquiring new ground in the highly-prospective Mesoproterozoic Bangemall Basin at Kumarina, 200km north of
Meekatharra in WA.
The Kumarina exploration project is the largest landholding in the Bangemall Basin and the company intends to conduct greenfield exploration there.
Ventnor is also well positioned to begin exploration of its tenements in western Queensland after it was awarded a $125,000 State Government drilling grant. Received in March, the grant is part of the Greenfields 2020 Collaborative Drilling Initiative (CDI) and will be used to progress exploration drilling in the Georgina Basin, 200km southwest of Mount Isa, to test for a possible iron oxide-copper-gold (IOCG) deposit.
The majority of Ventnor’s exploration during the March quarter was undertaken at its flagship Thaduna/Green Dragon copper project in WA’s Pilbara region and the company intends to announce a JORC-compliant resource for the project once the diamond drilling program has been completed.
Following this, Ventnor will begin active exploration on its Warrawanda/Nickel Hills project, also in the Pilbara.
The Kumarina exploration project Minimal exploration has been completed on the 1887 square kilometre Kumarina project area.
Sitting 75km northwest of Ventnor’s Thaduna/Green Dragon project, the Kumarina project is adjacent to highly-prospective copper exploration targets such as Horseshoe Metals’ Horseshoe Lights copper-gold project.
The western Bangemall Basin is also host to a number of other active exploration companies including Montezuma Mining Company, which is exploring the Butcherbird prospect 80km north of the Kumarina project, where high-grade copper mineralisation has now been successfully defined. Ventnor, which has accumulated the Kumarina landholding since mid-2011 through exploration licence applications, is using HyVista remote sensing mineral mapping technology to identify exploration targets.
The aerial mapping part of the HyVista survey has been completed and data analysis is now under way.
Fieldwork to verify the HyVista results will be conducted in the September quarter.
Ventnor managing director Bruce Maluish said that while this newly-acquired tenement was secondary to the company’s Thaduna/Green Dragon project, it was “in proximity to our main focus and nearby
active copper exploration prospects”.
He said the HyVista program would allow the company to economically and efficiently examine surface mineralogy over a large area and “pinpoint areas of interest for more intensive
“Surprisingly little or no exploration has been undertaken in this region,” Mr Maluish said.
“We now have an extensive contiguous holding in a highly-prospective area to undertake a new approach to greenfield exploration using modern techniques.”
The 4216-hectare Thaduna/Green Dragon project is an advanced copper exploration project within the highly-prospective Doolgunna district, 210km northeast of Meekatharra and 40km east of Sandfire’s Degrussa
Since listing on the ASX in early 2011, Ventnor has completed three phases of exploration at the site, involving more than 14,000m of reverse circulation (RC) drilling.
The Phase 4 drilling program commenced in January, and consists of 9000m of deep diamond core drilling down dip and along strike of the previously outlined mineralisation.
The program is designed to complete the resource drill out above 200m vertical and investigate the potential for economic mineralisation below 200m vertical along a strike length of 1000m.
A total of 145 RC drill holes for 18,700m and 15 diamond tails for 1517m have now been completed at Thaduna during the four phases of drilling.
At Green Dragon, 89 RC holes for 11,643m and two diamond holes for 390m have been completed. Ventnor discovered its deepest intersection to date in early March when drilling hit significant chalcopyrite/bornite mineralisation at Thaduna, returning copper sulfide intervals of 14m from 250.6m to 264.6m down hole.
Other significant results include 13m grading 2.87 per cent copper from 130m and 9m grading 2.68 per cent copper from 180m down hole, indicating the potential for further high-grade copper intersections.
Significant mineralisation encountered at the Green Dragon project include 10m grading 6.82 per cent copper from 34m, 7m grading 4.43 per cent copper from 75m and 19m grading 3.33 per cent copper from 63m.
The majority of Green Dragon mineralisation confirmed to date is chalcocite.
A deeper drilling program consisting of five diamond drill holes at Thaduna and 1000m of RC drilling at Green Dragon is currently under way, and final assay results are expected to be available in the next few weeks.
“These extra deep diamond holes have pushed our Phase 4 drill campaign out a little bit, but we will still expect to have a JORC-compliant resource by early July this year,” Mr Maluish said.
Based on drilling results to date, the company’s JORC resource projections at the Thaduna/Green Dragon project have been upgraded from 50,000 tonnes to 200,000t of contained copper.
Mr Maluish is confident the JORC-compliant resource will warrant a standalone project on the site, and expects operations to be up and running once final development approvals are received.
“We’re doing all the preliminary requirements to bring the project into production,” he said.
“We’ve lodged the mining lease application but there is still a fair bit of work to do.
“So I think it will take about a year to get approval and during that time we will finalise the circuit design.
“I expect in about two years we will be in production.
“The copper price is strong and is forecast to be strong for a while, and in two years’ time the forecast is that there will be a world shortage, so thecopper sector could be at the right place when we begin production.”
Ventnor’s exploration program this year will primarily focus on copper mineralisation at the Thaduna/Green Dragon project and a deep drilling program is currently under way to test the projected mineralisation at 280m to 320m below ground level.
Mr Maluish said that as the Doolgunna district had undergone active exploration, Ventnor had the advantage of being able to drill into a known resource.
“I think we’ve got a good resource that can be developed. Whether we develop it in conjunction with someone else or standalone, time will tell,” he said.
“It’s [the Doolgunna district] had a lot of activity in the last year, so I think this year we will see some very encouraging results coming out of that district and I would think that there could well be some more resources coming out of there too.
“It had existing pits, whereas everybody else has had to start from scratch, so we have a distinct advantage and that reflects in the time it will take to get other resources drilled out.
“There is a lot of activity in the area. I can see good numbers coming out of that district; I think the whole Doolgunna district will turn into a potentially significant copper province.”
The Georgina Basin project lies within the Proterozoic Mount Isa Inlier in northwest Queensland, which is one of the world’s most productive mineral provinces. It contains significant IOCG and massive sulfide deposits.
Ventnor was only recently granted eight exploration permits covering an area 2034sqkm, and is now in the process of finalising access agreements with pastoralists.
All Native Title issues have been dealt with and heritage agreements are in place.
There has not been any previous exploration for IOCG deposits in the basin and Ventnor will drill its first hole this year.
Due to the associated risks of drilling in unknown territory, the company has decided to take on a joint venture partner and is currently negotiating with various potential parties. A decision is expected in the next few months.
“The issue [with Georgina Basin] is that it’s quite deep cover, and is probably one of the last spots in Australia to be explored because of that,” Mr Maluish said. “So it’s risky, but to de-risk that a bit we are taking on a joint venture partner.”
Proposals for the CDI, which is designed to encourage drilling in underexplored areas of Queensland, were assessed by a panel on the basis of geoscientific and exploration targeting merit.
Ventnor’s CDI funding will be used to drill a single 1200m rotary mud pre-collar and a diamond tail to test an extensive magnetic and gravity anomaly that is consistent with the possibility of an IOCG deposit buried
beneath sedimentary cover.
The discovery of IOCG deposits buried under sedimentary cover is only possible through the use of advanced geophysical methods that identify prospective targets.
The drill target sits 600m below the surface and is covered by post-Proterozoic sediments, with the position thought to be highly prospective for IOCG deposits.
“First of all we will do some more geophysics in the area to refine the location of the drill hole, and then we will get a drill hole in there,” Mr Maluish said.
“We have a strong coincident magnetic and gravity anomaly which is a pretty compelling target and we would like to get a hole in there, but we will try and better refine the location first.
“The potential rewards are huge, but the risk is also very large.” Warrawanda/Nickel Hills
The Warrawanda nickel exploration project, about 40km south of Newman, lies within the Sylvania Inlier: an Archean granite-greenstone terrain in the Pilbara region of WA that remains relatively underexplored.
The Nickel Hills project is 12km north of the Warrawanda project and the two projects total 11,216ha.
In early April 2011, the company completed an airborne electro-magnetic geophysical survey over both nickel prospects. A 13-hole RC drilling program has also been completed.
The drilling program and further mineralogy work at the Warrawanda project area have confirmed the presence of nickel sulfides with a number of potential mineralising systems.
While no exploration was undertaken at the Warrawanda/Nickel Hills prospects during the March quarter, Ventnor expects to begin drilling again later this year, once drilling at the Thaduna/Green Dragon project is completed.
“We’ve targeted a couple of locations at both projects, but really haven’t had the time or personnel to get over there as well,” Mr Maluish said.
“There won’t be a lot of drilling, but we would like to get a couple of holes in: about a couple of thousand metres at each project.”
By Helena Bogle