Collisional Orogeny in the Scandinavian Caledonides: Drilling the Main Caledonian Décollement and into the Basement of the Fennoscandian Shield
Project Acronym: COSC-2 | State: Moratorium | Expedition ID: 5054
The COSC project focuses on the mid Paleozoic Caledonide Orogen in Scandinavia in order to better understand orogenic processes, both in the past and in today's active mountain belts.
The Scandinavian Caledonides provide a particularly well preserved example of Paleozoic plate collision, with the underthrusting of continent Baltica beneath Laurentia and thickening of the continental crust to at least 100 km. In the Scandes, the surface geology in combination with geophysical data provide control of the geometry of the Caledonian structure, both of the allochthon and the underlying parautochthon-autochthon, and define the targets for drilling. The drillholes themselves will help us to better define the structure and physical conditions of the allochthons and underlying parautochthon during nappe emplacement.
Click here for information on the first phase of the COSC project.
Keywords: Europe, Sweden, Basement Deformation, Foreland, Natural Hazards, Paleoenvironment, Paleozoic, Post-weichselian Temperature Development
Cores are stored at Federal Institute for Geosciences and Natural Resources, Spandau, Germany
Project News (click for all News)
2020-21-07
COSC-2 reaches 2000 m. Already last night we and the cake were ready for 2000 m. But, and some say because of this, the drill bit wore out at 1996 m. 20 hours and a round trip later: 2000 m! We are still drilling through the volcanic succession and are approaching the last prominent seismic reflector.
2020-08-08
The drilling at the COSC-2 site is successfully concluded. A big thank you to the on-site science team and the technical/drilling team. The main borehole (COSC-2A) was drilled to 2276 m. Overall, drilling went well. After mobilisation the operations started on 14th April. Down to 1575 m, the the core diameter is 61 mm (H-size) and from 1575 to 2275 m it is 45 mm (N-size). The borehole is now open (uncased) below the 100 m surface casing. The geology of COSC-2A held some surprises for us, mainly the level of main Caledonian décollement, the stratigraphy of the "imbricated section" and the type of basement encountered.
2020-07-16
This borehole is a thriller. Small details often cause long delays. After the change to the 6 m core barrel (double tube), however, overall drilling performance has increased and we get 6 m of very nice drill core every 4 hours.
- COSC-2A reached 2000 m
- 2020-08-08
- Change to 6 m core barrel
Project Management
Project Details
Project Timeline
Moratorium COSC-2
31 July 2022 - 31 July 2025
Sampling Party COSC-2
27 June - 8 July 2022 in Berlin-Spandau, Germany
Drilling
14 April - 7 August 2020
Full Proposal COSC-2 Approved
First Full Proposal COSC-2 Submitted
Workshop COSC-2
12-14 October 2015, Uppsala, Sweden