Skip to main content
ins.: 2020-05-05 10:41; ( Age: 4 yrs )
By: Scientists
Category: COSC_

COSC2: 2020-05-04

After adjustments to the drilling, bit life increased considerably.
Drill core is still very nice and recovery complete

After adjustments to the drilling, bit life increased considerably. After 175 m with the same drill bit, we reached 700 m this evening and the drill core is still very nice and recovery complete. We continue to drill through the turbidite unit, which now shows gradual changes in lithology: The coarse grained fraction increased considerably, partly accounting for up to 90 % of the drill core while the thin shale units become darker, rich in organic matter, sometimes almost resembling anthracite. This is most likely a sign that we approach alum shale, whose first continuous horizons we expect in about 50 - 100 m (according to the combined interpretation of seismic and magnetotelluric data from the site investigations) at the top of an about 500 m thick imbricate unit that overlies the basal Caledonian décollement