Satellite imagery may cast light on lithium reserves

Lithium supplies will underpin electric car market growth (Nissan)

13 July 2018

A Cornish lithium prospector is attracting international interest after revealing promising results from a research project using satellite observation to offer a new and cost effective way of identifying potential mining sites.

Cornish Lithium, founded in 2016 by Jeremy Wrathall – a former investment banker who trained in mining engineering at the Camborne School of Mines in Cornwall – has been working with the UK’s Satellite Applications Catapult plus experts from the British Geological Survey (BGS), Terrabotics, Telespazio Vega UK and the Camborne School of Mines among others.

England’s most south-westerly tip has a long and auspicious history of mining – copper and tin – but the industry finally called it quits two decades ago, dislodged by competition from Australia and the Far East. Today, it is among the country’s poorest counties – fantastic Poldark landscape and tourism not withstanding. Wrathall got the idea to look for lithium when a friend trying to reopen the South Crofty tin mine mentioned that there was lithium in brine in the mine. A search through historical records revealed the presence of lithium in underground hot springs across Cornwall.

Demand for lithium is expected to sore over the coming years as it is a vital component of batteries in electric cars and for storage of renewable power.

An £850,000 grant from the UK government’s Innovate UK fund has provided the means for investigating the potential for remote and in-situ data as indicators of what lies beneath vegetative cover.

The team used data at different resolutions from Landsat, Sentinel-2, WorldView-3, GeoEye-1, ASTER, Sentinel-1, ALOS-1 and TerraSAR-X satellites, along with ground survey data from the BGS and radiometric and magnetics data. These were combined with other techniques, such as heat mapping, to look for potential indicators of lithium in vegetation cover. Anomalies related to plant health and temperature were correlated with rock alteration and geological faults creating a picture of where lithium is more likely to be present at depth.

“This approach to lithium exploration, which includes the estimation of multiple surface indicators, has not been attempted before, and may be highly applicable across the wider mining industry. We are now looking at how we can improve this new tool which is attracting international interest from major lithium producers worldwide,” said Dr Cristian Rossi, principal Earth observation specialist at the Satellite Applications Catapult, who led the study.

The team also developed a digital environmental baseline map to show priority habitats, flood risk areas and urban settlements. As environmental monitoring and compliance with environmental regulations for a mining operation can cost around 5% of total project costs, a cost-effective tool for providing independent data is hailed as another attractive feature of the study.

The next phase of the study is to increase understanding of the sub-surface environment.