COSC-2 finished drilling during the night from Friday to Saturday at 2276.05 m depth. Unfortunately, the last round trip to change the drill bit was in vain but no major geological changes were expected in the following tens of metres. Our present assessment is that all objectives of the drilling operations are fulfilled. The geology had some surprises for us, mainly the rocks in the imbricated zone and the type of basement that underlies the sedimentary units (see earlier posts). Below ~1200 m, we lost correlation with the seismics. This issue will be addressed by re-processing and re-evaluation of the data based on the information from the up-coming downhole logging campaign.

During Saturday early morning, the borehole was flushed with clean water. Then the HQ drill string that acted as temporary casing was slowly rotated free and tripped out. At present (Sunday evening), the last hundreds of metres of NQ drill pipe are being tripped out, leaving the hole open (uncased) below the100 m long surface casing. We expect to finish all work on the COSC-2 main hole during the night. Not time for party yet (but for a BBQ!) because tomorrow, the drill rig will be moved some metres to core a
short hole that covers the upper 100 m (to the bottom of the surface casing, which was hammer drilled).