TO: Tom Davies

FM: Carlos A. Alvarez Zarikian


JA Daily Science Report for Expedition 306, 28 March 2005.




SCIENCE UPDATE: Cores 306-U1313A-1H to 24H had been recovered by 2355 hrs for a total of 223.7 m of sediment and a recovery of 104.3%. Sediments in the core catcher from Core 24H are of early Pliocene age (5.09-5.54 Ma) according to nannostratigraphy.

Most sediment from Cores 1H to 5H is mainly composed of moderate to highly bioturbated nannofossil ooze, foraminifer nannofossil ooze and silty clay foraminifer nannofossil ooze. Core 1H exhibited up to 20% diatom content. The top of Core 1H was characterized by brownish (10YR 8/3, 10YR 7/3, 2.5Y 7/4) sediments while the rest of the core down to Core 5H were dominantly medium light gray (N6), with light olive gray (5Y 6/2), light gray (5Y 7/1), olive yellow (5Y 6/6), and greenish (5Y 6/3) mm-cm thick laminae. Pyrite halos were common. The Bruhnes/Matuyama boundary was identified at the top of Core 5H (~33.9 mbsf), and the Jaramillo Normal Polarity Zone from 42.1 to 45.3 mbsf.