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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.
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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
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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.
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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 suboptimal—although 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, and—perhaps most important of all—an 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 community—and 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.
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Representative terms from entire chapter:
seafloor imagery
