Geologists can decipher the past climates and thus better understand how future climate change may affect the Earth's complex systems. In this paper, we report on a workshop held in Longyearbyen, Svalbard, to better understand how rocks in Svalbard (an Arctic archipelago) can be used to quantify major climatic shifts recorded in the past.

The Collisional Orogeny in the Scandinavian Caledonides project provides insights into the deep structure and bedrock of a ca. 400 Ma old major orogen to study deformation processes that are hidden at depth from direct access in modern mountain belts. This paper describes the successful operations at the second site. It provides an overview of the retrieved geological section that differs from the expected and summarises the scientific potential of the accomplished data sets and drill core.

For this paper, ca. 55 km high-resolution reflection seismic data were interpreted using constraints from magnetotelluric, potential field, and geological data. The resulting integrated geological-geophysical section through the central Caledonides in Sweden provides new insights about the regional tectonic setting, and supplies the basis for siting the second drill hole of the Collisional Orogeny in the Scandinavian Caledonides (COSC) scientific drilling project.

The Collisional Orogeny in the Scandinavian Caledonides (COSC) scientific drilling project successfully drilled a 2.5km fully cored borehole (COSC-1) through allochthonous subduction-related high-grade metamorphic gneisses and into the underlying thrust zone. This paper summarizes the scientific rationale of the project and presents first preliminary results.