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By Øystein Sture, Kurt Aasly, Ben Snook, Sigurd A. Sørum

INTRODUCTION Efficient exploration methodologies for base metal deposits have huge benefits for future deep sea mining endeavours, and underwater hyperspectral imaging (UHI) has been variably demonstrated to have applications in the identification and characterisation of mineralisation on the seafloor for both nodules and seafloor massive sulphides (SMS) (Dumke et al., 2018 and 2017 respectively). Due to growing resource requirements (Singer, 2017), SMS deposits are considered to be increasingly significant sources of copper and zinc, as well as silver and gold. This style of mineralisation is currently occurring at active hydrothermal vents (black and white smokers) but now-inactive sites also have the potential to be large mineral deposits. As such, the development of novel methodologies to detect both on-going and extinct mineralisations are of high importance. Geological setting During the MarMine cruise (Ludvigsen et al., 2016), non-mineralised host rock, low grade ore and high grade ore grab samples (Snook et al., 2018) was collected by ROV from the Loki’s Castle deposit (Pedersen et al., 2010), located on the Mohn’s/Knipovich junction on the ultra-slow spreading Arctic Mid-Ocean Ridge (AMOR), at a depth of approximately 2300 m. This material has been characterised as part of the MarMine project (e.g. Snook et al., 2017), and, by imaging compositionally constrained material, the measured hyperspectral responses can be used to generate a library for identification of deposits on the ocean floor. UHI technology Remote sensing with hyperspectral and multispectral technologies has seen wide use in prospecting for ores and hydrocarbons on land (Van der Meer et al., 2012). Iron oxides and sulphides have low blue reflectance and high red reflectance in the visible spectrum. The ratio between these two pairs has been used in exploration for terrestrial deposits of hydrothermal origin (Sabins, 1999). This discrimination typically also includes wavelengths exceeding the visible spectrum (1.5µm – 2.5µm). These wavelengths are typically not utilised underwater because infrared wavelengths and higher are rapidly attenuated in water. However, discrimination based on the full shape of the spectral response in the visible light (350nm – 800nm) may still be possible (Bolin and Moon, 2003). Resolving the endmembers from the spectral responses requires prior knowledge about the optical properties of the materials, i.e. their reflectance. These reflectances can be obtained in a controlled environment, where the spectra of the lamps, wavelength- dependent attenuation in water and scattering of light can be accounted for (Johnsen, 2013).

Jan 1, 2018

By S. Rajendran

Gas Hydrates (Methane Hydrates) are solid, ice-like substances composed of water and natural gas. They occur naturally in areas of the world where methane and water combine at appropriate conditions of temperature and pressure and are found in ocean bottom sediments and in some permafrost areas. Besides temperature and pressure, factors like bathymetry, sediment thickness, sedimentation rates, and total organic carbon content (TOC) also control gas hydrate formation in the ocean basins. The stability of gas hydrates depends on the critical combination of high pressure and low temperature (0 - 17 bars, 0 - 25°C), which in turn is dependent on the mix of gases from which the mineral is formed. As the critical parameters can be altered by deposition, erosion, slumping, formation or melting of ice cover, rise and fall of sea level, and sudden temperature changes induced by tectonic activities, current flow, or volcanisms, the gas hydrates tend to be very unstable. The Indian offshore is promising for the occurrence of gas hydrates in a total of about 80,000 km2 area in the bathymetry range of 700 to 3000 m as reported in earlier surveys. A gas hydrate stability zone thickness map was prepared using bathymetry and sea bottom temperatures along the continental margins of India. This map is expected to provide the depth window while searching for Bottom Simulating Reflectors (BSR). The study indicates that a minimum water depth of 750 m is required for the formation of gas hydrates, above which the chances for gas hydrate occurrence appear minimal despite other favorable conditions like organic-rich sediments, etc. Single-channel seismic analog records (Gupta et al., 1998) indicate that the Western Continental Margin of India (WCMI) offers a greater promise for gas hydrate occurrences, particularly with regard to the number of BSRs traced on the analog records as compared to earlier surveys.

Jan 1, 2005

By Ning Yang, Sup Hong

INTRODUCTION Metal components contained in deep-seabed mineral resources are being highlighted as “energy metals”, which are widely utilized in the entire fields of energy: harvesting and generation, storage and transportation, and saving. Those are mostly trace and rare metals, and rare earth elements as well: manganese, nickel, cobalt, copper, molybdenum, tellurium, selenium, platinum, etc. Toward low carbon society, for global sustainability, the role of metals and minerals is growing up in industries of energy and transportation [1]. In this context, the production and supply of energy metals from deep seafloor have to be approached also based on sustainable development. In deep-seabed mining activity, the sustainability is focused on potential impacts on ecosystems in benthic area and water column. The environmental impacts in deep-seabed mining are caused basically by intervention in benthic zones and transportation of materials. Those are, in particular, removal of benthic habitats, generation and dispersion of sediment plumes, surface transportation of seawater and sediment, tailing from mining vessel, sound and light noises, and chemical leakage, etc. This paper is aiming at fundamental guidance towards sustainable mining of polymetallic nodules.

Jan 1, 2018

By S. E. Boyd

Studies of benthic recolonization following the cessation of dredging in U.K. waters and elsewhere are limited, and are largely confined to experimental circumstances. Investigations of the physical and biological status of licensed areas in the U.K. at various times following cessation of commercial dredging are very limited and so judgments as to the likely progress towards environmental restoration and the time-scales are often based on predictions rather than real data. This study was established to address this deficiency by assessing the status of seabed substrata and associated benthic fauna within and outside areas where dredging had ceased and to conduct follow up sampling to monitor progress towards full recolonization.

Jan 1, 2004

By S. Naidu, J. Kelley, Roger Amato

The Alaskan Continental Shelf covers 76 % of the total shelf area of the United States. There are a lot of potential gravel deposits in the Alaskan offshore region. The gravel resources are currently not feasible for mining for the following reasons (U.S Congress, 1987): 1. Much of the glacial gravel is poorly sorted. 2. Gravel deposits are overlain by sandy and muddy layers. With the sea level expected to rise 70 cm in the next 100 years (Intergovernmental Panel on Climate Change, IPCC, 2001; Day, 2004), erosion of coastlines will be a major problem not only in Alaska but worldwide. Hence beach nourishment projects designed to minimize erosion will require large volumes of sand and gravel. Offshore areas will become a logical source for the fill material because of their proximity and ready availability. It is likely that future supply of coarse aggregate in Alaska may involve exploitation of marine deposits. The Chukchi Sea is a potentially favorable region for this type of mining because of extensive deposits of paleo beach and other relict gravel found in the near shore region (Stauffer, 1987). However a systematic analysis of potential gravel resource has not yet been conducted and it is the purpose of this research to estimate the size, extent and variability of gravel material that may be available in the continental shelf, offshore Kivalina.

By Ye Jun

Until now, more than 200 sites of sea-floor hydrothermal activities are known on the midocean ridge but few of them are documented on South Mid-Atlantic Ridge (SMAR). This on some extent restricts our directly understanding of the hydrothermal mechanism on SMAR. In 2011, During the Cruise 22 of R/V Dayangyihao, a masive sulfide field was discovered in the center part of the first-order ridge segment that bounded between Cardno Fracture Zone and Saint Helena Fracture Zone, near 15.16°S/13.35°W, which give us an opportunity to recognize the mechanism of hydrothermal systems on SMAR directly. This newly discovered hydrothermal field, which informally called SMAR 15°S, is situated in a SE-NW offset depression of an axial neovolcanic ridge, with water depth of about 2793m. In the water column around this field, strong turbidity and temperature anomalies were detected. Ten meters high venting chimneys, hydrothermal mounds as well as a large amount of hydrothermal vent shrimps were also observed and recorded by ROV and Deep tow camera on the ocean floor. The samples we collected from this field include sulfide chimney fragments, massive sulfides and basaltic rocks. In this study, we are focusing on the mineralogy and sulfur isotope geochemistry of sulfide samples for preliminarily uncovering the geological characteristics and hydrothermal processes of this hydrothermal field.

Sep 14, 2011

By Peter E. Halbach, Andreas Jahn

Co-rich hydrogenetic ferromanganese crusts are typical marine interface products of growth processes taking place on sediment-free substrate rocks on the seafloor. They grow very slowly and preferentially in water depths below the oxygen-minimum zone (OMZ) and have so far been found even in water depths of up to more than 5000 m, i.e. also below the calcite compensation depth (CCD); these deep ferromanganese crusts are particularly rich in Fe. It is assumed that the O2-minimum zone is the most important source layer of dissolved manganese, the decomposition of fecal pellets here also contributes to this Mn-budget. The process of hydrogenetic precipitation is basically an inorganic colloidal-chemical as well as a surface-chemical mechanism. Microbial mediations can be assumed, in particular since steps of redox-reactions are involved. The two main components of the hydrogenetic substance are hydrated d-MnO2 (vernadite) and x-ray amorphous Fe-oxyhydroxide, both of which are intimately intergrown with each other forming the extremely fine-grained hydrous oxidic material. In seawater, elements occur as dissolved hydrated ions or as inorganic as well as organic complexes which, in general, have either a positive or a negative surface charge depending on the pH of the respective marine environment. These complexes form hydrated colloids that interact with each other or with other dissolved hydrous metal ions. The main agent to oxidize the dissolved Mn2+ ions is oxygen, transported upwards from deeper water by turbulent eddy diffusion and turbulent rise processes at seamount slopes.

Jan 1, 2017

By Carl H. Hobbs

The beach at the resort city of Virginia Beach, Virginia has been and increasingly will be dependent upon artificial nourishment for maintenance and for hurricane protection. Both existing base-level maintenance operations and planned substantial enhancement programs out strip the capabilities of traditional terrestrial resources to provide the required quantities of sand. Our research program, an amalgam of projects from several funding sources, has located and defined suitable quantities of beach quality sand for use on the city's beaches. The work also has furthered our understanding of the region's Quaternary history. Initially, reconnaissance level, high-resolution, sub-bottom profiles and surficial grab samples taken on the basis of sub- marine geomorphology identified two geographically and geologically separate areas worthy of further exploration. Further profiling supplemented with some cores further defined the potential sand reserves. The Sandbridge Shoal site is a large and discrete Holocene sandbody atop late Pleistocene strata. The sands in region offshore of the commercial area known as the Resort Strip appear to be recent fill within fluvial(?) channels cut into the older subsurface. Each of these resources is within roughly 5 km of major sites targeted for beach nourishment and/or hurricane protection and contains sand with appropriate geotechnical properties. Ongoing work will better define the dimensions and limits of the sand bodies and provide data to enable determinations to be made concerning exploitation. Ultimately decisions concerning the overall beach enhancement-hurricane protection projects will involve economic, environmental, technical, and social considerations.

Jan 1, 1995

By Richard T. Haworfh

The United Nations Convention on the Law of the Sea (UNCLOS) entered into force, for those nations who had ratified it, on November 16, 1994. The Convention deals with nearly every aspect of ocean affairs, including marine scientific research, fishing zones, freedom of the high seas, protection of the marine environment and deep seabed mining. Article 76 of the Convention defines edge of the continental shelf in a way that many earth scientists find bizarre. Out to this limit, a coastal state has sovereignty over the seabed and sub-seafloor resources. Beyond that limit, the key principle of UNCLOS, that "the resources of the deep seabed represent the common heritage of mankind and should be developed to benefit all nations" is invoked. Establishing that limit and managing development in the different areas of jurisdiction is no small task. Canada's continental shelf as defined by UNCLOS covers an area approximately equal to half the area of the Canadian land mass. Interpretation and application of the convention is therefore highly significant for Canada. For example, the sedimentary basin in which the offshore Hibernia oil field is found, extends beyond the 200 mile limit but lies predominantly within the limits of the (UNCLOS) continental shelf. Responsibility for development of inshore placer deposits rests firmly with the coastal state. However, development of deep sea mining, in which the international community plays a management role under UNCLOS, has raised many concerns. Of particular interest to Canada will be the application of the provisions of the convention to interest in the polymetallic sulfides sampled on the mid-ocean ridges such as the Juan da Fuca Ridge. A further complicating factor for Canada is management of fishing stocks. Canada has sought to resolve this "problem" through multilateral negotiations under the UN. Under its "Oceans Act," currently being debated by Parliament, Canada intends to become a world leader in oceans and marine resource management. Similar activity in most maritime nations is setting the stage for a revolution in the way in which use of the world's oceans is managed. Much of this revolution will be guided by UNCLOS. Coastal states that have ratified the convention have ten years in which to define the limits of their continental shelves the clock is already ticking for them! We have yet to see how their actions will guide, or be guided by, those who have not yet ratified. We also have yet to see how national legislation and aspirations will mesh with international conventions that were drawn up in a previous era of environmental standards. This is a time in which many questions have been raised and few firm answers received. However, we must ensure that everyone is aware of what is happening, with what potential consequences, in order that rational decisions can be made. Canada has taken a few small steps that it is happy to share with the world community.

Jan 1, 1996

By John W. Padan

What is known about manganese nodules and their potential commercial recovery is outlined in terms of economics, legal rights, environmental impacts, and mineral genesis. As a result of 20 years of accomplishments it is clear that nodules comprise a real resource, and that they can be collected in water depths up to 5000 m, for brief periods, and raised to a surface vessel at rates of production appropriate for scale model systems. Based upon information in the public domain at present there is more confidence in the nature and magnitude of the resource than in the ability to recover nodules commercially. A review of the literature suggests that the metallurgical processing of manganese nodules is technically feasible and that the associated costs are well predictable. What is less clear is the market outlook for the products. All "overlapping claim" conflicts have been resolved. Therefore, parties with a historic interest in nodule mining appear now to have the right to mine in the future, assuming they properly complete whatever exploration license obligations they may have.

Jan 1, 1989

By Paul C. Rusanowski

Mining is a waste intensive industry, oftentimes producing hundreds of kilograms of waste rock and tailings for every gram of metal recovered. Disposal of mine tailings is a major concern in most mining operations. In Southeast Alaska the steep terrain and high seismic hazard province limits cost effective opportunities for land disposal of tailings. The lack of infrastructure and long travel distances generally limits secondary utilization of tailings, as well. Since the mines are located close to tidewater, submarine tailings disposal is an attractive option for tailings management. At the present time the EPA will not issue a permit that authorized marine tailings disposal from any mining process that includes flotation technology. Upland disposal is the "Best available technology" and must be used. Consideration of submarine disposal is generally precluded because the tailings are contaminated with fluids from the flotation process. However, when developing technological solutions to minimize environmental disturbance, destruction, pollution, and risk, submarine tailings disposal deserves another evaluation. In Southeast Alaska it may be the "Best available technology" based on an assessment of all issues and concerns in these mining projects.

Jan 1, 1991

By Michael Goldin, Jonathan Ladner, Thomas Peacock, Nathaniel Johnson, Patrick Haley, Kris van Nijen, Andrew Rzeznik, Pierre Lermusiaux, Matthew Alford, Carlos Munoz-Royo

Surface processing vessels for deep-sea nodule mining operations will produce dewatering plumes that will be released at some depth into the ocean water column. We are studying all aspects of this part of the nodule mining process. First, we have developed analytical and numerical models to determine the effects of highly non-uniform, realistic stratifications on forced, compressible plumes with finite initial size. The classical plume model is developed to take into account the effects of compressibility and thermal conduction through the dewatering pipe. Our results show how small-scale features of a realistic stratification can have a large effect on a plume, and provide a basis for determining at what depth dewatering plumes can be released. These results form the basis for our PLUMEX field experiments, in which we will study the dynamics of dewatering plumes over the course of one week of field tests from the vessel R/V Sally Ride. The field experiments will use a Remotely Operated Vehicle (ROV) and a Phased-Array Doppler Sonar (PADS) system to study the characteristics of the dewatering plumes. The subsequent transport of the material in the dewatering plume will be monitored via shipboard surveys and, potentially, Autonomous Underwater Vehicle (AUV) operations, and these studies will be integrated with near real-time, data assimilating numerical model predictions. The ultimate goal of this project is to develop a field validated, recommend strategy for the release and monitoring of dewatering plumes, to help inform the development of ISA regulations and the planning of industrial operations.

Jan 1, 2017

By G. Cherkashov

The geodiversity of seafloor massive sulfides (SMS) deposits at the slow- and ultra-slow spreading ridges is of great variety (Fouquet et al., 2010). Tectonics and magmatism are the two principal factors which control SMS formation and localization. The geological setting of SMS deposits is determined by their position relative to the rift valley and by the types of rocks hosted (Table 1). Depending on the first parameter, SMS deposits could be localized at [ ] the axial volcanic ridge or at the flank of the rift valley. Basalts, deep-seated gabbro, and serpentinized peridotites are distinguished among the hosted rocks. The outcrops of deep-seated rocks are exposed at the flanks of the rift valley. The tectonic mechanism of the lower crust and mantle rocks exhumation process is connected with very large offsets along the detachment faults, resulting in a forming oceanic core complex (OCC) (Smith et al., 2006; MacLeod et al., 2009). The SMS related to OCCs are represented by such ore clusters as Ashadze, Logatchev, Semyenov, and some others (Table 1) and are increasing steadily in number. This fact in combination with widespread OCC formation at the slow-spreading ridges (Escartin et al., 2008) and high grades of metals in SMS related to OCCs has provoked considerable scientific and economic interest in these types of deposits. It could be mentioned in this regard that the first two applications to the International Seabed Authority for prospecting and exploration of sulfides have been submitted for the areas in the spreading centres with wide distribution of the core complexes.

Jan 1, 2011

By J. Robert Woolsey

The Marine Minerals Technology Center (MMTC) was established by Congress in FY 1988 as part of the Mineral Institutes Program, administered by the U.S. Bureau of Mines under the auspices of the Department of the Interior. The primary objective of the MMTC is to encourage the development of selected mineral materials from U.S. seabeds by providing opportunities for appropriate engineering systems research, development, and technology transfer within academic, government, and industrial communities. The center will also provide the leadership and facilities required for the education and training of the nation's scientists and engineers in the field of ocean mineral development. Because of the broad spectrum of study encompassed by the field of ocean mining and mineral resources, the MMTC is organized to include separate divisions for nearshore and deep ocean research. The Continental Shelf Division is administered by The Mississippi Mineral Resources Institute (MMRI) of the School of Engineering at The university of Mississippi. Operational activities will be based at the John C. Stennis Space Center near Bay St. Louis, Mississippi and the Gulf Coast Research Laboratory, Ocean Springs,

Jan 1, 1988

By D. J. Scarratt

Fisheries make a significant regional contribution to the economy of Canada. In the Atlantic Region, over 70 thousand workers depend on the primary or secondary fishing industry. Fisheries are vulnerable to pre-emption of space by other marine industries and to contamination by chemical discharges. Markets may be affected even by the threat that products may be tainted. Fish may be killed by drags and dredges, and their physiology and behaviour affected by suspended sediments are stirred up by mechanical devices. Virtually no evidence exists of adverse impacts £ran ocean mining on fisheries, but projections from other marine activities such as fishing itself, dredging and other marine discharges give reason for caution. Department of Fisheries and Oceans policy calls for review of ocean mining proposals to ensure adequate protection of fish stocks, fishing activities and fish habitat, and compensation for losses attributable to any industrial project. Adverse impacts can be minimized by careful attention to details of location, technology and timing, and to close co-operation and information exchange between industry and the regulatory agencies.

Jan 1, 1985

By Mikhail D. Ageev

The paper concerns with some questions of Autonomous Underwater Vehicle (AUV) control system design, which allows a motion at rough undersea terrain. The AUV advantages reveal itself completely during exploration of such objects as seamounts and reefs area. These objects are characterized by steep slopes (30 degrees and above) and chaotic situated obstacles (rock debris, pinnacles, escarpments). Uses of other technical facilities for operating in such formations are difficult, dangerous or impossible. These regions take an interest due to the presence of iron-manganese crusts. Modern AUV can estimate density of mineral by means of still camera or video recorder. For this reason the vehicle has to move with the distance of 3-5 meters from seabed. Under such conditions micro- and mesorelief presents a considerable danger for AUV. The AUV can bypass underwater obstacles in the various ways. However, in any case AUV motion will be characterized by intensive maneuvering on various speed (from 0 up to 1.5 m/s), circular change of tractive force vector and, hence, a circular flow about the hull. So, AUV is equipped with the propulsion system, which provides free modes of motion. AUV control system (CS) has tri-level structure to allow a motion in a rugged seabed terrain. According to the generally accepted categorizations, CS includes execution, coordination and strategic levels. The strategic level contains the goals of AUV mission. Obstacles avoiding and route choice are realized by means of simultaneous maneuver in vertical and horizontal planes. Sonar system is used for data acquisition about obstacles. It consists of a few echo-sounders with fixed directivity pattern. The route choice algorithm operates at two lower levels of CS. Basic (?reflex?) functions of spatial motion are realized within the execution level and considered in the paper. The choice of motion modes is carried out at the coordination level of system. All accessible navigating information (the data from flight sensors and from multichannel echo-sounder systems) is used for this purpose. In addition the bypass of characteristic types of obstacles is carried out with the help of basic motion modes combination. The modeling results of bypass of various typical obstacles, and also their combinations are described in the paper.

Jan 1, 2011

By Robert G. Ditchburn, Cornel E. J. de Ronde, Bernard J. Barry

The age of mineralization, its mode of formation, the time elapsed to amass an economic deposit, its capacity for sustainable extraction and, ultimately, its grade and tonnage, are key aspects in the economic viability of volcanic massive sulphide (VMS) deposits (Ditchburn et al, 2004). Radiometric dating methods applied at GNS Science have been recently refined with the purpose of efficiently determining the ages of seafloor VMS mineralization along active intraoceanic arcs. These developments include: determining the longevity of seafloor hydrothermal systems, details of individual chimney and massive sulfide mound growth, and insights into deep-seated processes, such as the transfer of elements from magmas to their overlying hydrothermal systems. In our pursuit to better understand seafloor hydrothermal systems along intraoceanic arcs, we have thus far compiled age information for three volcanic centres of the Kermadec arc (South Pacific) and one of the Mariana arc (NW Pacific).

By Valery M. Yubko

During the last ten years seven applications for nodule-bearing areas of the World Ocean Floor International Region (IR) have been made by national companies of Russia (Yuzhmorgeologiya), France (IFREMER/AFERNOD), Japan (DORD), India (The State Department of Sea Resources Development), China (COMRA), Korea (KORDI) and the Interokeanmetal Joint Organization (IOM) of some East European countries and have been registered by the Preparatory Commission of the United Nations International Seabed Authority (ISA). Besides these groups registered within Resolution 11 of the Final Act of the III United Nations Conference on the Law of the Sea there are four international consortia registered in the USA [Kennecott (KCON), Ocean Mining Associates (DMA), Ocean Management Incorporated (OMI), and Ocean Minerals Company (OMCO)], which have interest in areas in the IR and can be considered as potential applicants. All registered areas (with the exception of the Indian Ocean) including the areas of potential applicants and also 6 areas, reserved for the ISA are located in the Clarion-Clipperton Zone of the Pacific Ocean. If within each area not less than one deposit of polymetallic nodule-bearing ores can be discovered, then, the total number of such deposits, for the present moment, is 20.

Jan 1, 1994

By Benjamin W. Haynes

The Federal government has a lengthy history in supporting and conducting research in the ocean mining and minerals field. The Federal effort has been and is currently focused primarily in four agencies: the National Oceanic and Atmospheric Administration (NOAA) within the Department of Commerce, and the Geological Survey (USGS), the Bureau of Mines (BuMines), and more recently the Minerals Management Service (MMS) within the Department of the Interior. While NOAA and the USGS have played dominant roles in mapping and geologic studies, and the MMS has recently provided funding for several task force studies within the Exclusive Economic Zone (EEZ) , the Bureau of Mines has conducted research in mining technology, minerals processing, resource definition, and economic evaluation of minerals from the seabed for over 20 years. These studies have yielded considerable minerals information regarding manganese nodules and crusts, placers, mineral sands, phosphorites, and sulfides. This paper reviews the past achievements in ocean mining and minerals programs starting in the late 1960's, describes current research and information efforts, and presents an outlook for Bureau of Mines research and information gathering efforts. Specific topics

Jan 1, 1989

By Lu Jun

Up to now, much data on marine minerals, as well as on marine geochemistry, have been accumulated. Modem computer databases provide optimum flexibility and power for manipulating these data. The best worldwide marine mineral database is currently the Marine Minerals Bibliography and Geochemical Data Base created by Carla Moore et al. at the National Geophysical Data Center in the United States. In fact, in the course of studying marine minerals and geochemistry we may collect not only digital-character type data but also graph and image (black-white, grey and color image) data types. For instance, correlation diagram between chemical compositions of minerals, spectroscopic graphs, (e.g. infrared spectra, Mossbauer spectra, etc.), grey or color images from both optical and electron micro- scopes (scanning or transmission electron microscopes) as well as seabed photographs. Charles L. Morgan et al. (1993) reported that 10,000 photographs and some video images of the seabed in the Clarion-Clipperton region of the northeastern tropical Pacific have been collected by the Ocean Minerals Company. If both graphic and analytical information were stored in a database, it would be very useful and convenient to marine geologists. This system would not only be able to search for all the data based on one parameter, but also for both size and composition distributions. If possible, geostatistical methods could be combined with fractal dimensional methods. Of course, this would require enormous efforts. Before multimedia technology emerged, it was very difficult to create image databases. The emergence of large-capacity compact discs, high-speed central processing units, and high-speed digital signal processing techniques makes it possible to establish multimedia database management systems (DBMS), image-text DBMS, that involves graphs, text, images, and sound. In order to store image fields in a DBMS, we have to take into account two problems: (1) image access format and (2) image compression code standard.

Jan 1, 1994