Personnel changes and onshore briefing logistics

Because Expedition 319 extends over a four month period and involves an initial phase dedicated to preparations related to riser drilling, the expedition will be staffed in three, partially overlapping phases (Fig. F17). The initial phase (5 May to 4 June 2009) will involve only the Chief Project Scientists and an EPM. At the end of this initial phase (4 June) the Chief Project Scientists are replaced by two Co-Chief Scientists (Byrne and Araki) and joined by eleven members of the science party who remain on the ship for ~45 days. In the final staffing phase, one of the Co-Chiefs and all of the science party are replaced (over a three-day period, 17–20 July) by a third Co-Chief (Saffer) and a second group of eleven scientists. To ensure continuity as the science parties rotate in the middle of the expedition, Co-Chief rotations are planned to be out of phase with the rotations of the science parties and a fourth Co-Chief (McNeill) will be on the ship during the transition in science parties. As a result, one Co-Chief (Araki) will return to the ship for the last 22 days of the expedition. Finally, short debriefing periods with selected Specialty Coordinators are planned between the staffing phases (~3–5 June and 16–21 July) and at the end of the expedition (31 August). This will help keep the Specialty Coordinators informed of progress and problems encountered during the expedition, and allow them to help guide the science party and Co-Chiefs through any decisions that must be made because of any special situations that may arise.