TO: Tom Davies
FM: Jay Miller
JA Daily Science Report for Expedition 305, 30 January 2005.
SCIENCE UPDATE: Cores 305-U1309D-168R to -171R (818.2 to 837.4 mbsf, 95% recovery) are medium-coarse grained gabbro. A thin seam of oxide gabbro is in Core U1309D-168R, however, the rest of the cored interval is modally homogeneous. Intervals of coarse-grained gabbro are common, and many contacts between coarse-grained and medium-coarse grained intervals are sharp and subhorizontal, although gradational transitions in grain size are also present. Alteration is intense in some places, but in general the rocks are less than 20% altered.