Greenwing Resources’ latest geophysical analysis reveals the San Jorge lithium brine system extends to 1,000m depth with increasing lithium grades, setting the stage for a significant resource expansion.
- Brine system extends to 1,000m depth, over twice previous drilling depth
- Lithium grades rise with depth, reaching up to 248 mg/L Li
- Brine body remains open laterally and at depth, indicating growth potential
- Zelandez appointed to lead scoping study and deeper drilling program
- Maiden Mineral Resource Estimate based on shallower drilling at 195 mg/L Li
Brine System Revealed to Reach 1,000m Depth
Greenwing Resources Ltd (ASX:GW1) has unveiled compelling new insights into its San Jorge Lithium Brine Project in Argentina, where a magnetotelluric (MT) geophysical survey indicates the lithium brine system extends to approximately 1,000 metres below surface. This depth is more than double the 402 metres reached by the company’s initial drilling campaign, which only scratched the surface of the brine body.
The MT data, integrated with earlier geophysical and drilling results, portrays a thick, highly conductive brine layer resting above Permian basement rocks. Notably, the brine extends beneath volcanic lava flows and gravels, suggesting a concealed and extensive resource footprint that remains open to the west, north, and at depth.
Lithium Grades Climb with Depth, Surpassing Current Resource
Perhaps more significant than the brine’s depth is the discovery that lithium concentrations increase as drilling goes deeper. Samples from the lower sections of the six drill holes returned lithium grades up to 248 mg/L, notably higher than the current resource average of 195 mg/L. This gradient hints at untapped zones with richer lithium concentrations, offering a dual opportunity to expand both the size and quality of the resource.
Such a trend is not without precedent in regional lithium brine projects, where deeper horizons have historically yielded higher-grade mineralisation. This sets a promising stage for Greenwing’s next drilling phase, which will prioritise these deeper, higher-grade zones.
Resource Growth Potential Supported by Geophysical and Drilling Data
The company’s maiden Mineral Resource Estimate, released last year, pegged the deposit at 1.07 million tonnes of lithium carbonate equivalent (LCE), divided into 0.67 Mt Indicated and 0.4 Mt Inferred categories. However, this estimate was constrained by drilling limited to a maximum depth of 402 metres near the salar boundary.
The MT survey’s revelation that the brine system extends to nearly 1,000 metres and remains open laterally suggests the current resource could be just a fraction of the total lithium endowment. The San Jorge project’s consolidated 38,000-hectare landholding, including 100% ownership of the San Francisco Salar, provides ample room for exploration and expansion.
Greenwing’s Managing Director, Peter Wright, emphasised the significance of these findings, noting the “clearest picture yet” of the brine system’s potential and the strategic importance of targeting the deeper, higher-grade brine. He also highlighted the appointment of Zelandez Limited, a lithium brine technical advisor with a proven track record, to manage the upcoming scoping study and drilling program.
Strategic Advancement with Zelandez and Scoping Study
Following the announcement earlier this month that Greenwing had engaged Zelandez to lead the scoping study, the company is now moving to design a drilling program that will test the deeper brine body identified by the MT survey. This next phase aims to materially increase the Mineral Resource by expanding both the volume and grade of lithium mineralisation.
The scoping study will leverage the detailed subsurface model derived from combined MT, TEM, seismic, and drilling data to evaluate development pathways, processing options, and economic frameworks. This approach aligns with the company’s broader strategy to advance the San Jorge project within a lithium market facing structural supply challenges.
Greenwing’s recent move to initiate a scoping study with Zelandez has been a pivotal step in project advancement, as highlighted in their April 8 announcement, underscoring the growing confidence in San Jorge’s potential and the company’s commitment to unlocking value through methodical exploration and evaluation.
Bottom Line?
The San Jorge project’s deeper, higher-grade lithium brine zones open a new chapter in resource growth, but the scale and timing of expansion hinge on upcoming drilling results.
Questions in the middle?
- Will the next drilling campaign confirm the extent and grade of the deeper brine zones?
- How will the scoping study outcomes influence Greenwing’s development timeline and capital requirements?
- What impact could a materially larger San Jorge resource have on lithium supply dynamics in Argentina?