Outokumpu Deep Drill Hole

Mica schist

Pegmatitic granite

Serpentinite, skarn, black schist = Outokumpu assemblage

Depth (m) Lithology

Main

ore b

elt

Prot. metasediments

Prot. granitoids

0 100

Mica schist

Pegmatitic granodiorite

Serpentinite, skarn, black schist = Outokumpu assemblage

Study site – Details

• Drilled 2004 – 2005 • 2516 m deep• Ø 22 cm• Uncased beneath 39 m• Fractured ~ 1.9 Ga crystalline

bedrock• Temperature + 40ºC at the

bottom• Salinity up to 70 g/L

Sampling at Outokumpu

Tube samplingLeutert Positive Displacement Sampler

Sampling by the ICDP Operational Support Group

Sampling at Outokumpu II

5

Research and results

• Research projects 2007-2014: Deep Life (Academy of Finland), GEOMOL, KABIO, SALAMI (Research programs on nuclear waste management): Microbiology by VTT, geochemistry by GTK

• Isotope studies: H2O, CH4, Noble gases =>…– Origin, evolution, residence time of groundwater

• Geochemistry, gas composition– Nutrients, energy source of deep life

• Diversified microbial community– Depth, geology(?), water chemistry

High salinity and abundant gases

7

Methane isotopes, microbial diversity

8

Future

• Outokumpu DDH not drilled for microbial purposes (only)• But may serve as a reference site• Potential for future research•