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Years 5Of Scientific Ocean Drilling SPECIALUNCORRECTED ISSUE ON SCIENTIFIC OCEAN DRILLING: LOOKING TO THE FUTURE PROOF Years of Scientific5 Ocean Drilling By Keir Becker, James A. Austin Jr., Neville Exon, Susan Humphris, Miriam Kastner, Judith A. McKenzie, Kenneth G. Miller, Kiyoshi Suyehiro, and Asahiko Taira ABSTRACT. Nearly a century after the first systematic study of the global ocean and drilling in 1961 using the Global Marine seafloor by HMS Challenger (1871–1876), US scientists began to drill beneath the sea- drilling barge CUSS I (Figure 1), to which floor to unlock the secrets of the ~70% of Earth’s surface covered by the seas. Fifty years four large outboard motors had been of scientific ocean drilling by teams of international partners has provided unparalleled added so it could operate as the first advancements in Earth sciences. Here, we briefly review the history, impacts, and sci- dynamically positioned drilling vessel in entific achievements of five decades of coordinated scientific ocean drilling. the world (Bascom, 1961). In a success- ful demonstration, phase I cored 170 m Miscellaneous Society (AMSOC). At that of sediments and 13 meters of underlying PROJECT MOHOLE (1958–1964) time, plate tectonics was yet to be formally basalt at a deep-water site offshore Baja The origins of scientific ocean drilling hypothesized, but it was already known California. Huge public interest devel- date back more than 60 years to Project from seafloor seismic refraction studies oped, thanks to a prominent article by Mohole. It was originally suggested in (e.g., Raitt, 1956) that the Mohorovičić the famous novelist John Steinbeck in Life 1957 by Walter Munk and Harry Hess, seismic discontinuity between crust and magazine (Steinbeck, 1961). Recovering and then proposed to the National Science mantle (Moho) was much shallower subseafloor basalt was a major scientific Foundation (NSF) by the famously beneath the ocean floor than the conti- accomplishment at the time, so much so named, partly self-organized American nents. NSF supported phase I of Mohole that it inspired a congratulatory telegram a FIGURE 1. (a) The drilling vessel CUSS I as used during phase 1 of Project Mohole. (b) A first examination of cores onboard ship during Project Mohole. b 14 Oceanography | Vol.32, No.1 UNCORRECTED PROOF from US President John F. Kennedy (Figure 2). However, the effort to con- tinue drilling to the Mohole was derailed by Congressional politics when it was evaluating various expensive proposals to build an appropriate, custom drilling ves- sel. As a result, Project Mohole had faded away by 1965. (See Munk, 1980; Maxwell, 1993; and Winterer, 2000, for many fasci- nating details of the Mohole story.) JOIDES AND THE DEEP SEA DRILLING PROJECT (1968–1983) Meanwhile, the directors of four major US oceanographic institutions (Lamont Geo- logical Observatory, Institute for Marine Sciences at the University of Miami, Scripps Institution of Oceanography, and Woods Hole Oceanographic Institu- tion) recognized the value of a concerted program to core the sedimentary record throughout the ocean. In 1964 they signed a memorandum establishing the Joint Oceanographic Institutions Deep Earth Sampling (JOIDES) program. Their vision was to propose to NSF separate scientific FIGURE 2. The congratulatory telegram from US President John F. Kennedy drilling “projects” operated by individual at the successful conclusion of phase 1 of Project Mohole. oceanographic institutions. The first JOI- DES project was a 1965 transect of holes across the Blake Plateau, managed by and DSDP for the 1975–1983 Interna- expedition cored and dated the basal Lamont and drilled by the chartered ves- tional Phase of Ocean Drilling (IPOD), sediments immediately above oceanic sel Caldrill. The Deep Sea Drilling Proj- which added an emphasis on penetrating basement in a transect across the South ect (DSDP) was the second JOIDES proj- the basaltic basement beneath ocean sed- Atlantic, confirming that crustal age ect, managed by Scripps starting in 1966, iments. In 1975, the first JOIDES Office increased nearly linearly with distance including construction of the drilling ves- was established (at Lamont-Doherty Geo- from the Mid-Atlantic Ridge spreading sel Glomar Challenger (see Spotlight 1). logical Observatory) to coordinate sci- center. In the summer of 1968, the University of entific planning for the program, with a DSDP was inherently explor- Washington joined JOIDES, and DSDP subtle change in its title “Joint Oceano- atory and global-ranging, and in that scientific drilling began with Leg 1 sedi- graphic Institutions for Deep Earth Sam- mode made many key scientific con- ment coring in the Gulf of Mexico, in the pling” (though the acronym remained the tributions—see the section below on western Atlantic offshore Bahamas, and same). Scientific ocean drilling has been Selected Achievements of Scientific on the Bermuda Rise. Originally proposed international ever since (Spotlight 2), and Ocean Drilling (1968-2018). DSDP also as an 18-month project, DSDP was so suc- has always been held up as a prime exam- made important technological contribu- cessful that it was extended through 1983. ple of successful international scientific tions, including development of deep- DSDP remained an NSF-funded Amer- collaboration (e.g., Smith et al., 2010). water reentry capabilities (1970) and the ican effort through 1974 as the National Revelle (1981) provided an early sum- hydraulic piston corer (1979) for soft Ocean Sediment Coring (NOSC) pro- mary of the scientific impact of DSDP. to semi-lithified sediments that contin- gram. Between 1973 and 1975, more US The most famous DSDP result may well ues to be the workhorse of the science institutions and the first international have been direct verification of sea- of paleoceanography (see Moore and partners (Spotlight 2) joined JOIDES floor spreading by Leg 3 in 1968. That Backman, 2019, in this issue). Oceanography | March 2019 15 a OCEAN DRILLING PROGRAM the European Consortium for Ocean community was small, and development UNCORRECTED(1983–2003) Research Drilling (ECORD), primarily and reviewPROOF of drilling expedition plans DSDP was formally concluded in 1983, to access shallow-water and high-latitude was often top-down. However, during and Texas A&M University was named scientific targets not suitableb for either of ODP and the various phases of IODP, all as the science operator for the Ocean the other drillships. proposals have been reviewed in the con- Drilling Program (ODP), leasing a newer This multi-platform vision was for- text of a succession of community-driven, and more capable commercial drilling mally realized in late 2003 as the Integrated multi-year, overarching science plans vessel rechristened JOIDES Resolution Ocean Drilling Program (IODP), whose (Spotlight 4). Program-based review pan- that also included a number of state- operations began in summer 2004. The els and committees have evolved through of-the-art laboratories for initial anal- first decade of IODP was organized on the years, both in number and com- yses (Spotlight 5). Whereas DSDP had a model with a significant component of plexity, from a theme/region focus, with been exploratory, ODP was designed internationally commingled funding and added engineering, logging, and technol- as a more thematically driven program, strong central management provided by ogy panels/working groups, to the com- with drilling expeditions based on pro- IODP Management International Inc. paratively simple current model with a posals submitted to the JOIDES advisory (IODP-MI). Unfortunately, there were single panel of both “science” and “data” structure by the scientific community delays in launching Chikyu and in com- experts who vet all proposals for all plat- in response to multi-year science plans pleting the major overhaul of JOIDES forms and integrate anonymous external (Spotlight 4) developed in periodic inter- Resolution in 2006–2008. Within this first peer review. An environmental protec- national workshops (see section below on phase of IODP, available funding was not tion panel, with some members serving Scientific Ocean Drilling and its Advisory sufficient to achieve the original vision for decades, stands guard over the safety Structure). In this planning mode, ODP for full-time operations by the two drill- of operations. Since the beginning of was very successful across a broad range ships and one or two annual MSP oper- ODP ~35 years ago, the nurturing of pro- of scientific themes that gave the com- ations. Nevertheless, the first IODP ponents and their ideas has been the key munity 18 years of continued scientific (2003–2013) made very significant sci- to success, with spectacular results. The ocean drilling from 1985 to 2003. NSF entific and technological contributions program is open to scientists located provided the majority (about two-thirds) towards an impressive list of ODP/IODP throughout the globe, and has fostered of the financial support throughout ODP, accomplishments; highlights are listed in innovative and transformative science but there were also substantial financial a later section on Selected Achievements from the tropics to the poles, in every contributions from international partner of Scientific Ocean Drilling (1968-2018), ocean basin, and over every epoch of the countries and consortia (Spotlight 2). and achievements are documented in last 170 million years. much more detail by Stein et al. (2014). INTEGRATED OCEAN DRILLING For its second 10 years, IODP contin- EDUCATIONAL CONTRIBUTIONS
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