JA Daily Science Report for Expedition 312, 30 November 2005
LOCATION: Site 1256
SCIENCE UPDATE: Cores 193R to 195R recovered 63 cm of moderately altered basalt from 1353.1 to 1363.7 mbsf representing an average recovery of 5.9% at 0.5 m/hr. One piece contains a sheared quartz + sulfide vein possibly related to a highly altered dike margin. Despite the slow pace of advance and limited recovery hole conditions continue to be good. Although the present bit has only accumulated ~35 hr of rotation, it has been decided to trip the pipe after the next core. The C-9 bit will be replaced with a C-7 bit, which has a more aggressive cutting structure in the hope of improving recovery and penetration rate.