Deep Sea Sediments

'Deep-Sea Sediments' focuses on the sedimentary processes operating within the various modern and ancient deep-sea environments. The chapters track the way of sedimentary particles from continental erosion or production in the marine realm, to transport into the deep sea, to final deposition on the sea floor.

As part of its continuing program to stimulate superior basic research in the marine environment, the Office of Naval Research, Ocean Science and Technology Division, sponsored a series of closed seminar-workshops in 1972-1973. Each seminar focused upon one re search area of marine geology which is relatively new and in need of a critical evaluation and accelerated support. The subjects areas chosen for the seminars were: 1. natural gases in marine sediments and their mode of distribution, 2. nephelometry and the optical properties of ocean waters, 3. physical and engineering properties of deep-sea sediments, and 4. physics of sound in marine sediments. The objectives of each seminar-workshop were to bring into sharper focus the state-of-the-science within each subject area, to effect some degree of coordination among the investigators working within each of these areas and to provide the Ocean Science and Technology Division guidance for national program support. This volume.contains most of the papers presented at the semi nar on the physical and engineering properties of deep-sea sediments. The seminar was held at Airlie House, Airlie, Virginia on April 24- 27, 1973 and was organized and chaired by A. Inderbitzen. The at tendees were invited from among the leading investigators in this field from both the engineering and scientific disciplines. Each attendee was requested to prepare a paper within his area of spe ciality.

For years scientists viewed the deep sea as calm, quiet, and undisturbed, with marine species existing in an ecologically stable and uniform environment. Recent discoveries have completely transformed that understanding and the deep sea is recognized as a complicated and dynamic environment with a rich diversity of marine species. Carefully designed to provide practical information in an easily accessible format, Methods for the Study of Deep-Sea Sediments, Their Functioning, and Biodiversity covers how to investigate the biological components through analysis of their biodiversity. It also provides the protocols and methodological details needed to investigate some aspects of the functional biodiversity of variables commonly utilized to describe and understand the drivers of deep-sea ecosystem functioning. This volume contains detailed protocols for analyzing all benthic components from benthic viruses, prokaryotes, protozoa, foraminifera, to meio-, macro-, and megafauna. It includes step-by-step procedures, with additional notes on the crucial steps or possible difficulties arising from the analysis. Each chapter provides a brief introduction, a description of the sampling procedures and/or the sample treatment, and then the laboratory protocols, providing information on instrument setting and/or the solutions utilized. Each chapter also contains a visual scheme of the protocol for use during laboratory activities and for tracking each laboratory step. Linking information on biodiversity with the functioning of the marine ecosystems, the book covers all living components of the benthos. It provides practical information for anyone studying deep-sea habitats, their characteristics, functioning, and biodiversity.

After a brief introduction to the distribution of deep-sea sediments, we show how the activities of marine organisms cycle nutrients and other dissolved constituents within the oceans, and influence the rates at which both solid and dissolved material is removed to sediments. Chapter 3 reviews the carbonate system and ends with a brief excursion into palaeoceanography. We conclude by describing the biological and chemical processes that continue long after sediments have been deposited on the deep-sea floor.

Over 60% of the Earth's surface is covered with deep marine sediments, however, until the early 1980s, no comprehensive text books appeared to support the rapid expansion in the study of these sediments. While the whole field of marine geology has expanded enormously and entirely new disciplines, such as paleoceanography, have been developed, there remains a lack of reference texts on study techniques that investigators in the marine community can turn to. Minerals and Mineraloids in Marine Sediments is an optical identifica tion guide that I believe will become a standard reference text for use in the microscope analysis of marine sediment& and sedimentary rocks. The systematic collection of sediment cores from the deep ocean floor began in earnest with the Swedish Deep Sea Expedition, 1947-1948. Much of the microscopic examination of the sediments collected in these piston cores (10 m+ long) was conducted on separated grain mounts or thin sections of impregnated sediments. By the late 1960s a simpler technique of examining a mounted smear of the cored silt and clay size sediment on a microscope slide had become standard practice in American oceanographic institutions. This semi quantitative technique became the standard tool used in core description aboard Glomar Challenger through the 15 years of the Deep Sea Drilling Project (DSDP), 1968-1983. Visual percentage estimates of biogenic and mineral components were made using petrologic micro scopes.