TO: Tom Davies

FM: Carlos A. Alvarez Zarikian


JA Daily Science Report for Expedition 306, 31 March 2005.


LOCATION: Site U1313 (IRD3A), Hole U1313C



Downhole logging of Hole U1313B using the triple combo tool string concluded at 1300 hrs, and formation density and natural gamma logs were successfully correlated. Hole U1313C was spudded at 1440 hr and by 2340 hr Cores U1313C-1H to 12H had been recovered for a total of 107.2 m of sediment and a recovery of 104.8%. Sediment in the Core U1313C-12H core catcher is of late Pliocene age (~2.41 Ma) according to foraminifer and nannostratigraphy. At Hole U1313B, Cores U1313B-4H to 32H (24.9-300.4 mbsf) are mainly nannofossil ooze, nannofossil ooze with clay, foraminifer nannofossil ooze, and foraminifer nannofossil ooze with clay of very pale brown (10YR 7/4), light olive gray (5Y 6/2), light gray (2.5 7/1), and white (N9, 5Y 8/1) colors. Below Core 14H, white (N9) nannofossil ooze is predominant. The Bruhnes/Matuyama boundary was identified at 33.7 mbsf and normal polarity zones Jaramillo and Olduvai from 40.9 to 45.1 mbsf, and from 72.7 to 91.75 mbsf, respectively.