During International Ocean Discovery Program (IODP) Expedition 391, the Tristan-Gough-Walvis Ridge (TGW) hotspot track was cored in December 2021–February 2022. Its overarching objective was to recover basaltic rock from TGW edifices to understand the evolution of Walvis Ridge and related guyots. Significant cuts to the Expedition 391 operational plan were necessary as a result of lost time due to COVID-19 mitigation procedures. Because the R/V JOIDES Resolution will pass over Walvis Ridge during the transit from Cape Town, South Africa, to Lisbon, Portugal, prior to IODP Expedition 397, the 3 week transit provides an opportunity to drill one or two holes that were planned but not cored during Expedition 391. The transit schedule indicates that ~7 days of ship time will be available for this effort. Coring will be attempted at one or two sites, depending on weather and operational difficulties. The first site to be cored will be proposed Site GT-6A on the flank of the Gough track ridge. If time permits, coring will also be done at proposed Site TT-3A on the Tristan track, completing the proposed transect across the three chains of the Walvis Ridge guyot province. Two operational strategies are planned to address the limited timemore »
Expedition 391 Scientific Prospectus Addendum: Walvis Ridge Hotspot
This addendum to the International Ocean Discovery Program Expedition 391 Scientific Prospectus (Walvis Ridge Hotspot; Sager et al., 2020) incorporates minor coordinate changes to Proposed Sites CT-5A, CT-6A, TT-3A, TT-4A, TT-5A, VB-7A, VB-8A, VB-10A, VB-11A, VB-13A, and VB-14A. The revised site coordinates are documented in Proposal 890-Add2, which is available at http://iodp.tamu.edu/scienceops/expeditions/walvis_ridge_hotspot.html. In addition, because of adjustments to the R/V JOIDES Resolution operations schedule caused by the COVID-19 pandemic, the expedition was postponed by a year. At the time of publication of this addendum, the expedition is scheduled to start in Cape Town, South Africa, on 6 December 2021 and end in Cape Town, South Africa, on 5 February 2022. For a detailed description of the geologic background, scientific objectives, drilling and coring strategy, logging strategy, sample and data sharing strategy, and proposed sites, see Tables T1 and T2 in this report and the Expedition 391 Scientific Prospectus (Sager et al., 2020).
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