Now Sailing: South Atlantic Transect (Expedition 390)

Abstract from the Scientific Prospectus: The South Atlantic Transect (SAT) is a multidisciplinary scientific ocean drilling project that comprises two International Ocean Discovery Program (IODP) expeditions (390 and 393). These expeditions 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. The sediments along this transect were originally spot cored more than 50 y ago during Deep Sea Drilling Project Leg 3 to help verify the theories of seafloor spreading and plate tectonics. Given dramatic advances in drilling technology and analytical capabilities since Leg 3, many high-priority scientific objectives can be addressed by revisiting the transect. The SAT expeditions will target six primary sites on 7, 15, 31, 49, and 61 Ma ocean crust, which will fill critical gaps in our sampling of intact in situ ocean crust with regards to crustal age, spreading rate, and sediment thickness. These sections are required to investigate the history of the low-temperature hydrothermal interactions between the aging ocean crust and the evolving South Atlantic Ocean and quantify past hydrothermal contributions to global geochemical cycles. The transect traverses the previously unexplored sediment- and basalt-hosted deep biosphere beneath the South Atlantic Gyre from which samples are essential to refine global biomass estimates and investigate microbial ecosystems’ responses to variable conditions in a low-energy gyre and aging ocean crust. The drilling operations will include installation of reentry cones and casing to establish legacy boreholes for future basement hydrothermal and microbiological experiments. The transect is also located near World Ocean Circulation Experiment Line A10, providing access to records of carbonate chemistry and deepwater mass properties across the western South Atlantic through key Cenozoic intervals of elevated atmospheric CO2 and rapid climate change. Reconstruction of the history of the deep western boundary current and deepwater formation in the Atlantic basins will yield crucial data to test hypotheses regarding the role of evolving thermohaline circulation patterns in climate change and the effects of tectonic gateways and climate on ocean acidification.

Below is a sample of recent articles featuring IODP expeditions, samples, data, or related research. Please This email address is being protected from spambots. You need JavaScript enabled to view it. to request to post an article on this page. Journalists and communication professionals are encouraged to speak with the program's Media Contacts for photos or others resources.

• Analysing Ancient Marine DNA in Antarctic Sediments, Tasmanian Times
• Japan's Next Great Earthquake Probed by Deepest-Ever Scientific Ocean Drilling, Engineering and Technology
• Deep Drilling Offers Clues to Japan's Next Big Earthquake, Futurity
• How the Tibetan Uplift Affects Evolution of Westerly Circulation, phys.org
• Seabed Core Samples Could Reveal Links Between Climate and Hundreds of Thousands of Years of Eruptions, Earthquakes, Stuff
• Could Earth Scientists Create Their Own Equivalent to the James Webb Space Telescope?, Discover Magazine
• Stretching of the Continents Drove Ancient Global Warming Event, Phys.org
• An Ambitious Vision for the Future of Scientific Ocean Drilling, Eos
• Research Leads to Deeper Understanding of Ocean Currents, NSF Research News
• India's Monsoon is Unique - It's an Enormous Movement of Water and Energy Across Earth, The Times of India
• Million-Year Study Shows Warming Will Make Indian Monsoons More Extreme Says Geoscientist Kaustubh Thirumalai, The Times of India
• A Million Years of Data Confirms: Monsoons Are Likely to Get Worse, New York Times
• Science Drill Ship Sets Depth Record Off Japan, BBC
• Climate Change: A Small Green Rock's Warning About Our Future, BBC
• How an Ill-fated Undersea Adventure in the 1960s Changed the Way Scientists see the Earth, Vox
• Tracking Past Earthquakes Along the Japan Trench, EurekaAlert (AAAS)
• 100 Million Year Old Seafloor Sediment Bacteria Have Been Resuscitated, Scientific American
• Space dust found in Chicxulub crater confirms asteroid’s dinosaur-killing role, Imperial College London
• Tracking Arctic climate change from a Greenhouse to an Icehouse world, EurekaAlert (AAAS)
• Scientists solve a major climate mystery, Space.com
• Paleoclimate puzzle explained by seasonal variation, Nature
• Will warming bring a change in the winds? Dust from the deep sea provides a clue, NSF Research News
• Life in the Chicxulub Crater years after it was formed, AGU Advances
• How hot is too hot for life deep below the ocean floor? EurekaAlert (AAAS)
• Microbial diversity below seafloor is as rich as on Earth's surface, URI Today
• The mission to drill through Earth's crust, CNN World

International Ocean Discovery Program (2013- )

(last update April 2022)

Integrated Ocean Drilling Program (2003-2013)

Ocean Drilling Program (1985-2003)

Deep Sea Drilling Project (1968-1983)

Last updated October 10, 2022

Completed Expeditions (2014- )

Expeditions from previous scientific ocean drilling programs:

• Integrated Ocean Drilling Program Expeditions (2003-2013)
• Ocean Drilling Program Expeditions (Leg Summaries) (1985-2003)
• Comparative Statistics from ocean drilling programs