A deep research borehole was drilled in 2004-2005 in eastern Finland by the Outokumpu Deep Drilling Project of the Geologcial Survey of Finland (GTK). The 2516 m deep hole was drilled into Palaeoproterozoic metasedimentary, igneous and ophiolite-related sequnce of rocks in a classical ore province with massive Cu-Co-Zn sulphide deposits. The basic operations of the project included drilling the hole to 2.5 km depth with continuous coring, geophysical loggings using 20 different methods, as well as hydrogeological sampling and hydraulic permeability measurements. The Outokumpu Deep Drilling Project was carried out in an international framework, partly supported by ICDP.

The Outokumpu Deep Geolaboratory: the borehole is still open for national and international use as a deep laboratory facility for different short and long-period experiments to be carried out in the borehole.

KEYWORDS: Europe, Finland, Ophiolites, Precambrian, Saline Fluids, Thermal Regimes