Cover Image


View/Hide Left Panel

The meeting that took place during the week of January 24, 1972, became known as the Princeton Workshop after the Ivy League school where it was held. NSF's International Decade of Ocean Exploration (IDOE) Office provided the financial support for the meeting, which was an obvious good omen for future funding. More than 40 scientific leaders of the Earth sciences community from nations around the world including the United States, France, the United Kingdom, Canada, and the Netherlands attended.

The final report resulting from this workshop entitled Understanding the Mid-Atlantic RidgeA Comprehensive Program, (NRC, 1972) after numerous formal presentations, much debate, and late night dinners, contained five "high-priority field projects" including the following recommendation:

Interdisciplinary surface ship surveying and sampling on a small scale over critical areas on the Mid-Atlantic Ridge should be followed up in the most critical subareas by more detailed geological and geophysical investigations, using the capabilities of deep-towed vehicles and submersibles.

The report containing this recommendation also contains the following notice:

The study reported herein was undertaken under the aegis of the National Research Council with the express approval of its Governing Board. Such approval indicated that the Board considered that the problem is of national significance, that elucidation or solution of the problem required scientific or technical competence, and that the resources of the NRC were particularly suitable to the conduct of the project.

With this official endorsement for a comprehensive American Mid-Atlantic Ridge program, including the use of manned submersibles, Dr. Heirtzler and others could now move forward in formalizing a major joint program with the French, which would become Project FAMOUS.

Although Project FAMOUS would be best known for its first use of a manned submersible in the Mid-Ocean Ridge, it did, in fact, involve every major technological tool then being used by marine geophysicists and would set the example for subsequent Mid-Ocean Ridge investigations. The area selected for this intense investigation of the Mid-Atlantic Ridge was between 36 and 37° N latitude for a long list of reasons. We wanted to be in a region of favorable weather and near a good logistical support base, which in this case was Ponta Delgada in the Azores, but far enough away from its "hotspot activity" to ensure that we were investigating "a typical spreading segment" of the ridge.

The chief scientists of Project FAMOUS were, to no one's surprise, Drs. Jim Heirtzler and Xavier Le Pichon. Prior to the actual joint diving operations, which took place in the summer of 1974, they published the goals of the project in an issue of Geology (Heirtzler and Le Pichon, 1974):

Among questions that we hope to answer are the following: What is the detailed age distribution of the surface rocks in this zone? What is the relative importance of primary constructional features and secondary tectonic ones in shaping the morphology? Is the structure of the boundary zone steady state? And if not, to what extent? What is the distribution of the different types of igneous rocks with respect to the tectonic and volcanic features within the zone? Are large portions of the oceanic crust exposed along the obviously faulted scarps of the Rift Valley? What is the thickness and exact nature of the layer at the origin of the Vine and Matthews magnetic lineations? Are there metamorphic rocks (zeolites, greenschist, or even amphibolites facies) within the zone? What is their distribution with respect to the different tectonic features? Many other questions can be asked concerning the tectonics of the transform-fault area. One of the most important is how localized is the zone of shearing? Is there really a transform fault or a zone of transform faulting? What is the distribution of the ultrabasic rocks that occur within this zone? Is there volcanic activity within the transform fault? And so forth.

To address this long list of questions using traditional field mapping techniques, first and foremost required excellent topographic maps. This was particularly true for the Mid-Ocean Ridge given its complex morphology, but also because its morphology was a direct reflection of the volcanic and tectonic processes taking place within its rifted inner valley.

The first dives into the rift valley in 1973 used the French bathyscaph Archimede. In all, seven dives were made by the Archimede covering a 5-km2 area of the central high and the adjacent eastern marginal high. The central high was found primarily to be a constructional volcanic feature not significantly altered by subsequent tectonics. The central zone of extrusive lava flows was found to be bounded to the east, in the area the Archimede investigated, by steep vertical scarps up to 100 m in height thought to be volcanic flow fronts.

These preliminary dives clearly revealed that despite the tremendous lateral dimensions of the North American and African crustal plates, the actual zone of injection that includes surface lava flows is extremely narrow and ideally suited to submersible investigation. Had the boundary separating the spreading plates been broad, as reason might have led one to believe, the investigation of such a region by a manned submersible might have been an utter failure.

With these initial promising results, Project FAMOUS moved into its final phase in the summer of 1974 with the coordinated diving programs of the submersibles Alvin and Cyana and the bathyscaph Archimede and continued surface ship studies.

Never before had three deep diving submersibles carried out such a coordinated effort. Having more than one vehicle diving in the area added to the overall safety of the operations as described later, but it also had its drawbacks.

A critical aspect of the FAMOUS dives in the rift valley was a precise knowledge of where the vehicles were at any one time when observations were made, photographs taken,

The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement