TO: Tom Davies
FM: Jay Miller
JA Daily Science Report for Expedition 305, 22 February 2005.
SCIENCE UPDATE: Cores 305-U1309D-286R to -291R (1372.8 to 1396.8 mbsf, 87% recovery) are medium- to coarse-grained gabbro and olivine gabbro. Cores U1309D-287R and the top of -288R (1377.6 to 1380 mbsf) include a diabase with gabbroic xenoliths. No upper contact with the diabase was recovered, but there is a sharp, igneous lower contact with coarse-grained gabbro. Olivine is more abundant in the lower third of the cored interval. Intensity of alteration is low, and the gabbroic rocks are texturally isotropic other than subtle modal changes and grain size variations.