Editor's Note: Peggy Delaney is sailing on a newly refurbished research vessel, the JOIDES Resolution, that left Honolulu on March 10 with an international group of researchers on board. The ship, supported by the U.S. National Science Foundation, conducts scientific investigations beneath the seafloor by drilling the ocean floor and retrieving long “cores” of mud for testing and data collection. This is her twelfth blog post. To see all her posts, see "60 Seconds in the Mid-Pacific."

SOMEWHERE IN THE MID-PACIFIC (April 26, 2009)—I just came back inside from watching the rig floor crew trip pipe—that is, go through the process of extracting the over four kilometers (2.5 miles) of drill string that hung beneath the ship as we drilled the final hole at the final site (U1336B, for those keeping score). The last core came on deck around 2 A.M. last night. The scientists who were awake gathered on the catwalk to watch the process of receiving, labeling and sectioning the core one more time. The co-chief scientists, Heiko Pälike and Hiroshi Nishi, congratulated the rig floor crew for a successful operation.

So begins the end.

We are working on the site report for the second-to-last site, and we will have a meeting about that site today at 12:30 P.M. We are carrying out the analyses required to characterize the materials from this site. We write the equivalent of a book about the material recovered while we are on the ship, walking off with a complete version of descriptions of the material from every site as well as overview and summary material about how these cores will be used to address the scientific objectives of this expedition. Like many expeditions, the coring is just the start of the science. The shipboard descriptions are used to guide sampling for science we do on shore in the first year or so after the expedition.

We are skilled by now in the processes of how to describe this material, work the instruments, work the software. We have gone from being a group of separate scientists to working as a team. More than that, we have forged friendships of a unique and lasting kind with our shipmates. We have celebrated our joys together, and we have mourned our losses—both those of the expedition and those from the life at shore that has continued without us.

I was struck by this morning by the transformational opportunity shipboard life gives, as I prepared a sample tray in the chem lab. I had the Bluegrass Brothers playing from my music player over the lab stereo for all to hear. My lab mates included Kiseong Hyeong, a sedimentologist from the Korea Ocean Research and Development Institute, stopping in the chem lab to help with the ongoing and time-consuming task of grinding sediment samples in preparation for carbonate analyses; Ken Sawada, the organic geochemist from Hokkaido University, working on measuring the calcium carbonate and organic carbon content of these sediments; and Yulia Vasilyeva, a Marine Lab Specialist with the IODP (Integrated Ocean Drilling Program). I smiled to myself as I told my Korean, Japanese and Russian-American colleagues, "Don't worry, not even most Americans like the music I am playing for you!"

What now? Another boat drill tomorrow; the group photograph, usually taken on the bow; getting underway sometime this afternoon, after all the pipe is back on board in the rackers; finishing our work in the labs; shifting time zones one more time to get us back on Hawaii time; finishing our write-ups; meetings about sample-allocation decisions for after we get off the ship; transit—more than a week of it to reach Honolulu.

And the end of this expedition.

A group of scientists gather on the "steel beach" in hopes of catching a beautiful sunset, courtesy IODP