Click for next page ( 12

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

Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 11
INDEPENDENT ANALYSIS BY COMMITTEE INFORMATION NEEDS BASED ON USES The second course of investigation was to determine the data requirements related to specific EEZ uses or activities: oil and gas exploration and development, pipelines, hard minerals exploration and development, waste disposal (including monitoring), cables and military uses, cultural, biological resources (including monitoring), ocean energy, geohazard analysis, and shoreline management. Data requirements were keyed to the following data gathering activities: bathymetry, seafloor imagery, sediment characterization, near-surface profiling, geophysics, bottom sensing, optical imagery, in situ testing, and borehole logging. In considering the usefulness of mapping and information gathering systems to potential EEZ uses, it is important to distinguish between data obtained through a wide variety of surveying and bottom mapping tools and techniques, at different scales and accuracies, including water depth (bathymetIg), seafloor imagery (mostly acoustic, some photographic), subbottom profiling, and direct sampling of seafloor surface and subsurface sediment characteristics. Surveying and mapping of seafloor characteristics provide fundamental and essential data and information for resource development and environmental protection at different scales and accuracies and for different purposes. Reconnaissance surveys provide a broad overview of regional geology, seafloor morphology, rock or sediment type and large-scale features. High-resolution mapping is required for task-specific or site-specific suIveys. Based on the committee's review of the relevant literature, discussions with researchers and other experts, and their own expertise and judgment, priorities for types of information required for seabed uses and activities were ascertained. Bathymetry and sediment characterization are determined to be the highest ranked data needs. The results of these investigations are summarized in Figures 7A and 7B. Figure 7A presents the ranking of data type requirements for various classes of EEZ applications, with 1 as the highest level of need and 5 as the lowest. Figure 7B displays this information in a bar graph, with Highest interest" representing data types, ranked most frequently as first or second choice for priority, and "strong interests reflecting data types clearly useful for the identified applications listed in Figure 7A, but ranked to be of lesser priority. Bathymetry: NOAA is conducting high-resolution mapping in the EEZ with a multibeam bathymetry system. Prioritization is necessary because it will take NOAA's present high-resolution bathymetry systems three to ten times longer to cover the areas mapped by GLORIA Increasing the rate of coverage would require additional ships and acquisition of improved technology. Reconnaissance survey: The USGS is conducting surveys of the EEZ using a reconnaissance- scale side-scan sonar (GLORIA), which is towed near the ocean surface at 10 knots with a swath width 11

OCR for page 11
12 of 60 km. Interpretation of much of the detail seen on GLORIA images will require sampling in order to calibrate the attributes that are observed. Documentation of both bottom and sub-bottom formations would be greatly aided by a systematic grid of shallow penetration, high-resolution acoustic profiles as a frame of reference for sampling locations and as a key tool in mapping and interpretation. Seabed characterization: Accurate use-specific resource and site evaluations require ground truth information based on seafloor sediment samples. To date, seabed sampling activities have mainly been conducted as part of limited, special purpose or site-specific projects and as part of broader nearshore coastal studies. A coherent program of offshore sea bottom mapping extending into deep water is less well-defined. Sample recovery and characterization analyses are significantly more labor intensive and time consuming than the more automated digital data acquisition and processing that characterizes bathymetry, imagery, and acoustic profiles. The types of information that can be derived from a bottom sampling, coring, and profiling program are listed below. Sample attributes: Profile character: In situ testing: Lithology Mineralogy Organic content Ore mineral concentration Grain size, shape, and hardness Sorting Bed thickness Sedimentary structure Sequency character Cementation Solubility Porosity Permeability Acoustic properties Paleontology Radiation Toxicity Bed continuity and correlation Areal extent Layering geometries Stability indicators Compressibility Strength Fracture pressure Plasticity Density Permeability Velocity Temperature Conductivity The next round of user requirements analysis will attempt to define which attributes are most frequently needed and to determine analytical and descriptive standards that will maximize usefulness to a maximum number of potential users.

OCR for page 11
13 DATA MANAGEMENT ARCHITECTURE FOR SEABED INFORMATION A major objective of this assessment is to evaluate data management and dissemination aspects of EEZ activities and make recommendations for an optimum data management structure that encompasses all information gathered and the diverse interests of users. The independent analysis of information needs in relation to specific uses of the EEZ raised a number of issues related to data management needs, giving rise to the question of how the information that is collected can be made useful to potential users in terms of data availability and effective distribution systems. The committee's investigations into the information requirements associated with present and potential uses of the EEZ reveal that data management issues will become increasingly important and more difficult to deal with unless a complete systems perspective is adopted at the outset. More specifically, the data needs expressed by respondents to the committee's questionnaire suggest that analog, interpretive, map-based products are suboptimalalthough necessary products. Consequently, present practices in data processing, archiving, and dissemination should be carefully examined to ensure that both current and unforeseen future needs will be met in a timely and cost-effective manner. By adopting a systems perspective at this time, the EEZ program will be the beneficiary of a total systems architecture that embraces full consideration of current sensor technology, state-of-the-art data interpretation, and computer system components. A total system perspective is best suited to accommodate uncertainties that lie ahead: changes in sensor systems, new computer products, evolving analytic techniques, andperhaps most important of allan uncrystallized but rapidly developing clientele for the resultant data products. In essence then, a strategic user-oriented vision of the EEZ program must be developed. This vision will not only reflect the uncertainties of the user communityand therefore the need for flexibili~but also reflect the evolving character of technology needed to keep the EEZ program in the forefront of science and applications.

OCR for page 11