A multidisciplinary IODP investigation along a crustal flow line across the western flank of the southern Mid-Atlantic Ridge1
Julia S. Reece
Co-Chief Scientist Expedition 393
Department of Geology and Geophysics
Texas A&M University
1 Coggon, R.M., Sylvan, J.B., Teagle, D.A.H., Reece, J.S., Christeson, G.L., Estes, E.R., and Williams, T., 2022. Expedition 390/393 Scientific Prospectus Addendum: South Atlantic Transect. International Ocean Discovery Program. https://doi.org/
The South Atlantic Transect (SAT) is a multidisciplinary scientific ocean drilling project that will recover complete sedimentary sections and the upper ~250 m of the underlying oceanic crust along a slow/intermediate spreading rate Mid-Atlantic Ridge crustal flow line at ~31°S. These cores were originally scheduled to be collected during International Ocean Discovery Program (IODP) Expeditions 390 and 393 in October–December 2020 and April–June 2021, respectively. In 2020 and 2021, the global COVID-19 pandemic resulted in the postponement of several IODP expeditions, including Expeditions 390 and 393, chiefly because science parties were unable to travel to the R/V JOIDES Resolution. In response, the ship was used to conduct preparatory work for the postponed expeditions that did not require a science party aboard but could be carried out by the ship’s crew and a team of technicians from the JOIDES Resolution Science Operator. Two of these expeditions (390C and 395E) were in service of the SAT drilling project, to reduce the operational risks and expedite basement drilling during the rescheduled Expeditions 390 and 393. Expeditions 390C and 395E visited five of the six primary SAT sites and successfully cored a single advanced piston corer/extended core barrel hole penetrating the entire sediment section and <10 m into the underlying basalt before installing a reentry system in a second hole at each site visited. Given these accomplishments, the operations plans for the rescheduled Expeditions 390 and 393 have been revised.