The Geological Survey of Denmark and Greenland, or GEUS in short, hosted a group of young and enthusiastic geologists from the Geological Survey of Estonia (EGT). This 5-day training and field-work session was about learning new techniques, sharing knowledge, and developing long-lasting future cooperation pathways between the two organisations. 

The learning visit to Denmark and Sweden was also the first EGT-TWINN project's joint training in the long list of activities ahead. It took place on the 27.–31. March 2023. In this event, geologists Marko Kabel, Jekaterina Nezdoli, Tavo Ani and Johannes Vind from the EGT were trained by leading Danish geology experts Niels Hemmingsen Schovsbo (GEUS) and Arne Thorshøj Nielsen (the University of Copenhagen, Department of Geosciences and Natural Resource Management — IGN). Both of the latter are world-famous experts on Scandinavian geology and authors of numerous high-rated scientific articles, especially about sedimentary geology, regional basin dynamics, and related mineral resources. 

The study visit focused on the Cambrian geology of Scandinavia and its relevance for Estonia. The Cambrian period is interesting for critical raw materials (Alum Shale contains vanadium, a battery metal) and geothermal energy potential. 

The visit started at the GEUS drillcore repository in Copenhagen. Estonian geologists learned about the theoretical background of Cambrian palaeogeography, stratigraphy and sedimentology. They saw various drill cores from different regions, practised core logging skills and used a handheld-XRF device for rapid in-situ geochemical analysis. "It might  a beautiful beginning of potential fruitful cooperation between our two geological surveys," said senior geologist Tavo Ani after the core-archive visit. He explained further: "We have much to learn from GEUS when it comes to systematic drilling core management, sampling standards and overall organising of the workflows in the archive facility." Ani was excited about the prospect of inviting GEUS staff for a return visit to Estonia to introduce EGT Arbavere drill-core archive and soon-to-be-opened study facility.

Afterwards, the group travelled to Sweden to see the outcrops of Cambrian rocks in the field. They visited several locations on Öland Island, where they observed the Alum shale, siltstone and sandstone formations typical for the Cambrian in Scandinavia. They also visited sites on the mainland, such as the currently operational Skrylle quarry and abandoned Andarum Alum Shale quarry, where they saw more examples of Cambrian sedimentary rocks and fossils. The field trip was an opportunity to compare and correlate the Cambrian geology of Sweden and Denmark with that of Estonia and to learn from the experience and expertise of the GEUS and IGN staff who supervised them. 

"The most exciting about the fieldwork was to see the geological outcrops and sections in nature that we have studied only in scientific papers so far. Especially interesting was visiting the famous Middle to Upper Cambrian age outcrop in Andrarum historical Alum Shale abandoned quarry, where the biggest industry in Southern Sweden produced alum shalefrom 17^th to 20^th century ," described the EGT senior geologist Johannes Vind. He added: "Also, coming from a relatively small mining country like Estonia, and seeing the exploration capacities and extraction volumes on a completely another scale in some of the large Swedish mines is an eye opener in many ways for us."

The study visit was a valuable learning experience for the Estonian geologists, who gained new knowledge and skills to help them in future research and innovation activities. The EGT-TWINN project will continue until 2025, with more training events, workshops, conferences, publications and collaborations planned. The ultimate goal is to enhance the scientific excellence and societal impact of the EGT as a leading institution for geological research in Estonia.

The overall EGT-TWINN project aims to enhance the research and technical capacity of the EGT to support Estonia's transition to green energy by developing advanced skills and methods for geological resource assessment and exploration, and this visit to Denmark and Sweden was certainly a wonderful step towards that goal.