GTK investigates critical raw materials in Peräpohjola region of Finland

The Geological Survey of Finland (GTK) is investigating the availability of critical raw materials in the Peräpohjola region and is seeking additional information about the area’s bedrock, extending several kilometers deep. In September, GTK plans to measure a 70-kilometer-long seismic reflection line in southern Lapland, stretching from Lake Lohijärvi in Ylitornio to Tervola, reaching the road towards Sompujärvi. This area belongs to the Peräpohja schist zone, known for its rich mineral deposits.

Schist zones consist of bedrock layers originally formed in marine basins and altered through volcanic activity. These layers have since undergone geological processes that have lithified, transformed, and fissured the rock strata. The seismic reflection measurement involves placing 3,000 small seismic receivers along a road, creating a line approximately ten kilometers long, with receivers positioned every five meters.

Matti Niskanen, a geophysicist at GTK, explains that the area will be analyzed using vibrations generated by a 30-ton vibrating truck. The devices capture reflected signals from the bedrock structures over distances exceeding ten kilometers. The study, part of the broader REPower-CEST project, focuses on cobalt and copper, identified as critical raw materials by the EU, which aims to increase production within its borders.

Project manager Mari Kivinen highlights that the ongoing energy transition necessitates more metals, particularly for electric vehicle batteries, prompting a need for increased production within the EU. Efforts include mapping the current mineral potential of the area’s geology and exploring the potential for raw materials from abandoned mining waste areas.

Gravity measurements have commenced this year, with approximately 1,500 points surveyed so far, continuing through the end of the year. Based on these measurements and existing data, an updated predictive map of mineral potential will be produced.