Emerging sulphate of potash (SOP) play Trigg Mining (ASX: TMG) reports it has successfully completed its first drilling program at Lake Throssell, one of its two brine projects in Western Australia.
A total of 26 holes of shallow rotary drilling were completed across the playa area of the lake — playa being defined as an area of flat land in a desert basin from which water evaporates quickly.
The work followed up auger sampling that indicated Lake Throssell was a new high-grade discovery, the company said.
The holes targeted the surface aquifer and were drilled to a depth of 10m, with the samples now at a laboratory and with results expected this month.
A bulk sample of 600 litres was taken for future evaporation trials and for process flowsheet analysis for SOP production.
The company said this is the first stage of a comprehensive exploration of its high-grade Lake Throssell as it targets a maiden JORC resource.
The shallow surface lake program is targeting near-surface brine mineralisation to depths that will be suitable for trench-based extraction methods.
Many of the holes sunk in this program encountered strong brine flows with increased gypsum.
The gypsum layers were up to 20cm thick in some holes and were often associated with “good to very good” brine recharge rates, Trigg reported.
First ever drilling at project area
Rainfall over millions of years, carried through paleochannels below what is now desert, has accumulated beneath the surface with high potassium content and the area’s now high evaporation rate of about 3m a year has left large brine resources.
Trigg’s program is the first full on-ground drilling of Lake Throssell. It follows up the company’s auger sampling that identified high-grade surface brine samples of up to 6,700 milligrams per litre (mg/l) potassium, or 14,800 mg/l SOP with an average grade of 5,300 mg/l potassium, or 11,800 mg/l SOP.
The Lake Throssell SOP project covers about 694sq km of granted and pending tenements, within which there are 190sq km of salt-lake playa and 70km of underlying interpreted palaeochannels.
Trigg aims to secure sustainable Australian agriculture
The project is located 170km east of Laverton on the Great Central Road connecting Laverton, WA to Alice Springs in the Northern Territory.
Trigg said it is looking to secure Australia’s sustainable agriculture future through the exploration of essential potassium fertiliser (SOP), necessary for global food production and human nutrition.
SOP provides essential macro-nutrients for plant growth without any detrimental elements, such as chloride found in muriate of potash (MOP).
In addition, SOP can be produced sustainably through the solar evaporation of potassium-rich hypersaline brine water, without the need for large open pits or waste-rock dumps.
The company also has the Lake Rason SOP Project that covers 500sq km of granted and pending tenements.