Image of at-sea transfer of personnel.

At-sea transfer of personnel onto the ODP drill ship JOIDES Resolution , at Hydrate Ridge, off the coast of Oregon. The Observatory’s Borehole Research Group conducted extensive wire-line logging and logging-while-drilling operations to investigate the in situ properties of natural gas hydrates. Photo: Gilles Guérin

Fifty years ago, with the purchase and refit of a 200' pleasure yacht renamed the Vema, Maurice Ewing inaugurated Lamont's exploration of the largely unknown terrain beneath the world's oceans. Today, members of the Marine Geology and Geophysics (MG&G) Division remain explorers at heart, motivated by curiosity to understand these remote and forbidding parts of our planet. Over the years, the tools of exploration have improved from simple echosounders and towed seismic source-and-receiver instruments, to MultiChannel Seismic (MCS) Reflection techniques which allow us to probe more deeply into the Earth, and multibeam bathymetric and side-looking sonar imagers for mapping large areas of the seafloor in ever greater detail. While the surface ship has remained the "work horse" of MG&G research, other types of platforms and vehicles are playing an increasingly important role in our efforts. Among these are: submarines, particularly for under-the-ice work in the Arctic Ocean; satellites, with their ability to cover large areas of the oceans very rapidly (and revisit the same area many times); robotic vehicles, both tethered to a mother ship and free-swimming; and manned submersibles, the only way humans can travel to the floor of the deep ocean. It is fair to say that making new and exciting observations of geological processes occurring on and beneath the seafloor is a key element of research undertaken in the MG&G Division.

An early success of marine geophysical research was the discovery of seafloor spreading, which led to the general acceptance of plate tectonics as the broad foundation for understanding how our planet works. Communities of scientists have emerged to test hypotheses generated by the plate tectonics paradigm in the oceans. Notable among these recent, focused efforts are the National Science Foundation's Ridge 2000 and MARGINS programs, in which Lamont's MG&G scientists play leading roles. In addition, Lamont scientists have used ocean drilling data and technology to study the sediments and hard rocks beneath the seafloor, as well as the fluids that flow through them. One of Lamont's major contributions to scientific ocean drilling was the establishment of the Borehole Research Group (BRG) in the mid-1980s. The BRG is charged with providing down-hole geophysical measurement (logging) services to the Ocean Drilling Program (ODP), developing new types of borehole logging instruments, adapting oil-field logging tools for use in the ODP, and maintaining a database of all logging measurements on behalf of the ocean drilling community. Now, as we transition from the ODP to the new Integrated Ocean Drilling Program (IODP), with its more complicated international partnerships and its multiple drilling platforms, the MG&G Division is poised to play an even larger role in the ocean drilling science of the future.