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deployed to core continuously through
deep-sea sediment (project LOCO, LOng
COres). Maurice Ewing (Columbia
University, also a member of AMSOC)
supported obtaining multiple long cores,
stating, “The entire record of terrestrial
conditions from the beginning of the ocean
is there in the most undisturbed form it is
possible to find anywhere—and the dream
of my life is to punch that hole 2000 feet
deep and bring the contents to the lab to
study them” (Gray, 1956).
Thus, simultaneously with Project
Mohole, a different kind of program was
planned. Five U.S. oceanographic institu-
tions established JOIDES (Joint Ocean-
ographic Institutions for Deep Earth
Sampling). In 1965, using dynamic posi- Figure 1. Multichannel Seismic Line 1027 in Baltimore Canyon, used to locate the best sites (902,
904, and 906) during Ocean Drilling Program Leg 150 (Mountain et al., 1994). Cored intervals are
tioning, fourteen holes were cored in the shown in white. Also shown are the locations of Deep Sea Drilling Project Site 612 (Leg 95) and the
eastern Atlantic Ocean on board the Continental Offshore Stratigraphic Test (COST) B-3 well. The COST B3 well was used to establish
first-order age and facies successions. These sediments were cored to establish a history of sea-
Caldrill I. The results convinced the scien- level variations along the mid-Atlantic U.S. continental margin. Mission-specific drilling platform
tific community of the value of multiple Expedition 313 continued the coring in modern water depths of 30–35 m and recovered nearshore
and onshore sediments deposited during Neogene changes in global sea level.
holes throughout the ocean. In 1967,
Global Marine was contracted to design
a ship expressly for the purpose of SOD. Seven days later, Leg 2 began coring The JOIDES Resolution
With SIO as the prime contractor, the across the Atlantic. The scientific party of
Deep Sea Drilling Project (DSDP), using eight included two female micropaleoen- Ocean Drilling Program (ODP,
the Glomar Challenger, was launched tologists, Catherine Nigrini (SIO) and 1983–2003)
(Bascom, 1961). Maria Bianca Cita (Instituto di Geologia, By the late 1970s, JOIDES began
Universitá di Milano, Italy). This began a exploring alternative vessels. Major
Deep Sea Drilling Project (DSDP, tradition of international participation improvements in heave compensation and
1968–1983) that was formalized in 1975: five coun- station-keeping ability offered better cores
By 1968, several seminal papers on tries (Federal Republic of Germany, and an expansion of geographic areas that
plate tectonics (e.g., Hess, 1962; Vine and France, Japan, the Soviet Union, and the could be explored. More research could be
Matthews, 1963; Wilson, 1966) had been UK) became contributing international accomplished with expanded laboratories
published. These papers were based on partners in the International Phase of and more scientists. The SEDCO/BP 471,
sparse data, leaving many unconvinced. Ocean Drilling (IPOD). Today, 23 coun- an oil exploration vessel, was chosen,
Interpretation of marine magnetic anoma- tries are part of the IODP consortium, highlighting the advances in technology
lies (e.g., Pitman et al., 1968) and better and women comprise about half of the generated by the petroleum industry.
earthquake data (e.g., Isacks et al., 1968) science team. Funding for the new program came from
provided additional support for this the- Technological development continually the United States and member countries.
ory. For many, final confirmation came improved drilling, coring, and logging. Texas A&M University was awarded the
from SOD. In 1970, the first re-entry cone was contract. The SEDCO/BP 471 was con-
As with Project Mohole, whose objec- deployed (Leg 15, Site 146, Venezuelan verted to a scientific drilling vessel, the
tive was seismically defined, Leg 1 of the Basin), allowing the drill string to be JOIDES Resolution, and on 11 January
Glomar Challenger and all subsequent pulled, a new bit attached, and coring in 1985 commenced operations. Unlike petro-
expeditions have used seismic surveys to the same hole to continue. This enabled leum exploration, which relies heavily on
determine the ideal place to drill for sci- the drilling of deep holes through sedi- well logs and cuttings to understand the
ence (Fig. 1) and for safety reasons, such ment and into hard rock. In 1979 (Leg 64, geology of a location, SOD collects cores.
as avoiding overpressured hydrocarbons. Guymas Basin), the hydraulic piston core For most JOIDES Resolution legs, a ship-
Leg 1’s objectives in the central Gulf of (HPC) was deployed for the first time board scientific party would analyze cores
Mexico were clear; identify the cause of (Fig. S2 [see footnote 1]). Today, the and document findings during two-month
the reflectors on the seismic profiles, HPC and multiple offset holes at a single expeditions, working in two 12-hour shifts,
especially the domes and knolls on the site are routine for paleoceanographic seven days a week.
deep-sea floor, and recover the oldest expeditions. This allows construction of
ocean sediment. Leg 1 of DSDP was a complete “composite” stratigraphic Integrated Ocean Drilling Program
success. The domes were salt diapirs. records, essential for detailed paleoceano- (IODP, 2003–2013)
The oldest sediment was Jurassic, much graphic research (Figs. 2 and S3–S5 Despite the capabilities of the JOIDES
younger than expected. [see footnote 1]). Resolution, critical locations remained
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