The work of another expedition to Mongolia, whose aim was to search for critical raw materials (Mo and W) in the vicinity of Taishir, has been completed. The expedition lasted from 14 June to 4 July 2025.

The research area was located north of the Zavkhan River in the Govi-Altai Province, on the south-western edge of the Khangay Mountains. The field research was once again led by Rafał Sikora, PhD, from the Department of Regional and Deposit Geology of the Polish Geological Institute – National Research Institute. Marcin Kania, PhD, and Rafał Małek, PhD, from the same department, Andrzej Chmielewski from the Department of Raw Materials Policy, and representatives of regional branches Adam Kozłowski (Carpathian Branch) and Andrzej Piotrowski (Upper Silesian Branch) also took part in the research.

Similar to previous years, the work consisted of identifying crystalline rock formations and potential zones where valuable elements may be accumulated. During the prospecting, in-situ measurements were taken using portable X-ray spectrometers (pXRF), and samples were collected for lithogeochemical and petrological analysis. An additional outcome of the research will be the determination of the age of the crystalline rocks that make up the study area.

Polish expedition camp in Taishir (photo: R. Sikora)

Various types of Neoproterozoic and Late Palaeozoic granites and rhyolites dominate here, accompanied by occurrences of gabbros, gabbro-diorites and basalts (also Neogene). Locally, there are also carbonate rocks of the Neoproterozoic-Lower Cambrian Tsagaan-Olom group. The experience of researchers from PGI-NRI indicates that radiometric dating of rocks in this part of Mongolia may verify the current knowledge on this subject.

Sampling of sediment samples by Marcin Kania and Adam Kozłowski (photo: A. Piotrowski)

Sedimentation of samples. On the photo: Adam Kozłowski (left) and Andrzej Piotrowski (photo: R. Sikora)

Andrzej Piotrowski during the examination of rhyolite outcrops (photo: R. Sikora)

Rafał Małek during reconnaissance of granite outcrops (photo: A. Chmielewski)

Andrzej Chmielewski performing in-situ XRF measurements (photo: R. Małek)

Rafał Sikora uncovering rhyolites of the Neoproterozoic Zavkhan formation (photo: A. Piotrowski)
 

Rock thresholds are dry in summer, but water flowing during the thaw and heavy rainfall creates waterfalls in these places (photo: R. Sikora)

Fieldwork often required climbing steep rock faces developed along tectonic faults (photo: R. Sikora)

An important element of the work is contact with the local population, especially with the local administration. To this end, representatives of the Taishir District were invited to the camp, where they were introduced to the expedition participants and informed about the purpose and methods of the research. Our colleagues also emphasised their respect for the local nature and cultural traditions, which was very well received by those visiting the field base. As proof of the good relations, goat and sheep carcasses were purchased from local shepherds. In addition, the camp was open to passing nomads throughout its operation, and each visitor was offered food and drink. This type of behaviour is a tradition in this part of the world.

On 20-21 June 2025, the base was visited by a delegation of employees from the Polish Embassy in Ulaanbaatar, led by His Excellency Ambassador Krzysztof Bojko. This was another field meeting, also attended by local authorities. It was an official event, but this did not prevent it from taking place in a wonderful atmosphere with interesting discussions not only about the research being carried out but also serving as an opportunity to exchange experiences about Mongolia and other parts of Asia.

A group photo of the expedition participants and guests from the Polish Embassy in Ulaanbaatar, local authorities and nomads. The mountainous research area can be seen in the background (photo: Odkhuu)

As part of the promotion of Earth sciences and the presence of Polish geologists in Mongolia, a meeting was also held with pupils and teachers from a primary school in Taishir, during which discussions were held on geology and the interests of children and young people. At the end of the meeting, the school was presented with a guitar and a guide to identifying rocks and minerals, which were funded by members of the expedition.

Group photo of expedition participants with pupils and teachers from the primary school in Taishir (photo: Odkhuu)

Presentation of how to perform geochemical measurements in the field. Explained by Rafał Sikora, presented by Andrzej Piotrowski (photo: R. Małek)

Conversation with students about rocks, photographed by Rafał Sikora and Rafał Małek, translated by Dr Odpurev Ghankhujak (photo: M. Kania)

The moment when the guitar, funded by the expedition participants, is handed over to the school. Adam Kozłowski is the camp guitarist (photo: Odkhuu)

A guitar with the logo of the Polish Geological Institute-National Research Institute as a lasting proof of successful cooperation and our presence in Taishir, a gift from the expedition participants against the backdrop of the yurt door (photo: R. Sikora)

The work schedule was followed without any disruptions, and it should definitely be emphasised that the expedition also resulted in greater integration between PGI-NRI employees, i.e. the team got to know each other better while facing various challenges related to field work, camping together in yurts and sharing responsibilities.