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By Kira Mizell, James Hein

"INTRODUCTIONThe majority of studies on the genesis of ferromanganese crusts focus on the adsorption and accumulation of metals, and therefore cations, especially those of economic interest. From these studies, a first-order electrochemical model has been proposed based on the zero point of charge of the manganese and iron oxides at typical seawater pH, which assumes that positively charged ions will bind to the negatively charged manganese oxide phase and neutral and negatively charged ions will bind to the slightly positively charged iron oxide phase (e.g. Koschinsky and Halbach,1995; Hein et al., 2013). While the theory behind this model is sound, and it has been consistent for many elements, other elements may not follow the model (Koschinsky and Hein, 2003), and thus requires additional investigation and validation. As a new approach to understanding element accumulation in ferromanganese crusts and to test the proposed electrochemical model, this study investigates the surface chemistry of the halogens, which occur as negatively charged ions in seawater and have high and consistent concentrations in seawater.ResultsBulk Halogen ConcentrationsTo determine the distribution of halogens in ferromanganese crusts, an initial dataset of 24 FeMn crusts (24 bulk and 19 layer samples) from throughout the global ocean, including the Arctic and the Southern Oceans, has been analyzed for chlorine and fluorine content using ion-selective electrode. Although both Cl and F are conservative in seawater, their content in crusts shows striking variability (Cl: 326 - 13310 ppm; F: 146 – 1048 ppm for non-phosphatized crusts) and has no obvious geographic relationship to ocean basin and no correlation with water depth, latitude, or longitude. We plan to have bromine concentration data to present at the time of this conference."

Jan 1, 2017

By J. Robert Woolsey

This paper provides certain Southeastern coal-burning utilities with an economic strategy for complying with the sulfur dioxide emission standards set firth by the Clean Air Act Amendments of 1990. The strategy takes advantage of the occurrence of vast quantities of manganese nodules on the Blake Plateau offshore Georgia and the Carolinas, a commodity which as been proven to be a highly effective dry sorbent of sulfur dioxide. Using existing technology, manganese nodules could be mined and transported via barge directly to power plant sites, where they would be used as filter material for cleaning sulfur dioxide from the effluents of coal-fired power plants. Completely sulfated filter material could be treated for the extraction of by-product metals such as cobalt, copper, nickel, and manganese. The strategy may well be enhanced by the occurrence of ore grade phosphate rock in the same area of the Blake Plateau. This phosphate rock could be simultaneously mined to effect a reduction in production costs if it is found to be suitable for use as either a direct application fertilizer or as an acidulated superphosphate fertilizer. The manganese nodule-based strategy offers a retrofitting solution for existing power plants that would minimize the capital costs for compliance with the Clean Air Act Amendments and has the added advantage of providing a number of other metal or fertilizer by-products.

Jan 1, 1992

By Steven D. Scott

Several polymetallic sulfide deposits (copper, zinc, f lead, silver, f gold) presently exposed at the surface of the ocean floor are of sufficient size and apparent grade that they will someday be seriously considered as mineable resources. Responsible ocean mining may have some real environmental advantages over land mining, although they both share the same downstream problems caused by smelting and refining. The area of disturbance for an ocean mine would be much less than for an equivalent sized deposit on land around which considerable rock has to be excavated in order to get at the ore. Acid mine drainage, a very serious problem in land ming, would not be a concern in the alkaline and oxygen deficient environment of the deep ocean. There would undoubtedly be loss of habitat for some marine organisms but this could be minimized by mining deposits that are no longer hydrothermally active and therefore support little life. The risk of severe corrosion and thermal damage to the mining equipment at hydrothermally active sites would probably preclude their recovery in any event. The scientific community and environmental advocates should take advantage of the long lead time before ocean mining commences to insure that the environmental mistakes of the past, as encountered in some land mining, are not repeated. In order to fully understand and thereby mitigate the consequences of recovering seafloor sulfides, test mining of a small deposit using the German-designed high capacity television grab, preceded and followed by detailed observations of the mining site from a submersible, is proposed.

Jan 1, 1992

By Allan Spencer

In March 2007, Nautilus Minerals Inc. announced that they had commenced their 2007 exploration and development program with the mobilization of the Research Vessel Wave Mercury and the Survey Vessel Aquila onsite Papua New Guinea.

By Jan M. Peter

Many of the Pb-Zn massive sulfide deposits of the Bathurst area in northern New Brunswick, Canada, are intimately associated with laterally continuous iron formation (IF) (Figure 1). This IF is a fossil laminated, exhalative, chemical sediment. Together, the IF and the Brunswick #12, Brunswick #6, and Austin Brook deposits (rightmost discontinuous horizon on Figure 1) are collectively referred to as the "Brunswick Belt". To date we have only studied the Brunswick Belt and have not examined the horizon along which the QSR, CNE and Flat Landing Brook deposits lie. The Bathurst area is underlain by the Tetagouche Group (Figure 2), a Cambro(?)-Ordovician sequence of metasedimentary and bimodal metavolcanic rocks that was intruded by mafic to felsic plutons and subsequently deformed during the Taconic Orogeny. The stratigraphic sequence consists of shales and greywackes that are overlain by carbonaceous shales and felsic volcanic and volcaniclastic rocks; these are in turn overlain by mafic volcanic and sedimentary rocks. The massive sulfide deposits and IF occur within the upper portions of the felsic volcanic rocks in close association with carbnaceous metasedimentary footwall rocks (Figure 2).

Jan 1, 1993

By Lee Sung-rock

KIGAM (Korea Institute of Geoscience and Mineral Resources) has been doing various kinds of research works in marine minerals and energy resources exploration and utilization since early 1990s in Korea. In the presentation, the authors will introduce the recent research and development activities mainly focusing on the rare earth metals of the Pacific deep seabed Mn-nodules and gas hydrates which occur from Korean deep waters. KIGAM has been participating in the polymetallic manganese nodule exploration, mining and metal-extraction project, which is modulated by KIOST (Korea Institute of Ocean Sciences and Technology, formerly KORDI). Now KIGAM puts more focus on extracting precious and rare earth metals from the Mn-nodule as well as underlying sediments. The rare earth elements (REE) from seabed mineral deposits also draw attention to those countries including Korea which are lack in natural resources. KIGAM is doing several kinds of leaching experiments using various kinds of reagents under the different experimental parameters. Extraction of rare earth metals from deep sea nodule using H2SO4 and HCl solution showed good leaching effect. As the gas hydrates are to be evaluated as a new future energy resource globally, Korean government has initiated national R/D program covering fundamental exploration survey for resources assessment in Korean deep waters and production technology development. KIGAM plays a key role in seismic exploration, resources assessment, experimental

Sep 14, 2011

By Elisabetta Tedeschi, Razieh Nejati Fard

Deep-sea mining is in the future perspective of mining industry and it is currently in the technological development phase. The focus of this study is on the electrical power system that provides sufficient energy for the mining equipment at the seafloor, excavating Seafloor Massive Sulfide (SMS) deposits. SMS deposits usually exist at water depths between 1500 m and 4000 m. Despite the similarities of SMS deposits excavation to the open-pit terrestrial mines, more energy is required to drill and crush the ores in the hyperbaric conditions [1], which can be done whether by static trench cutters [1] or by mobile mining crawlers [2]. In addition, the ores vertical transportation by subsea pumps requires several MW electrical power that can be supplied by all-electric subsea motors or hydraulically from water injection motors located on the surface. The power requirements can be fulfilled by an offshore or subsea power network. As the SMS mines are usually in remote locations, the straightforward solution will be an isolated offshore grid mounted on a vessel or platform similar to the most of offshore Oil & Gas projects. These power systems resemble the onshore microgrids for industrial purposes operating in island mode. However, in contrast with the onshore power networks, there are space and weight limitations in offshore infrastructures, which impose the design compactness to be a priority. In addition, having a very high reliability is necessary in the design approach of the offshore projects due to the extraordinary high expenses corresponding to repair and maintenance. The other design criterion is to improve the power system efficiency in order to reduce the size of the power equipment cooling apparatus, operational costs and CO2 emissions produced by diesel/LNG onboard generators. There are a few studies considering power system distribution for seafloor mining industry. Among them, [3] has investigated the AC and DC alternatives for SMS mining in 2400 m water depth by considering Solwara 1 project scenario introduced by Nautilus Minerals Inc. [2]. In this study, a power system design tool will be presented taking into account various water depth, power consumption levels, different distribution configurations (AC and DC) and the aforementioned design criteria.

Jan 1, 2018

By Leonhard Weixler, Peter Platzek

The Company Bauer Maschinen is very well known in the field of specialist foundation equipment. In the diaphragm wall market, we have experiences both in manufacturing and executing projects all over the world since 1984. We have a population of more than 300 units working all over the world in all climate and soil conditions. Especially for hard soil and rock conditions, we have developed several cutting tools and systems to optimize the performance, e. g. the “flipper tooth” Besides the execution of land based foundation projects, we have performed our firs offshore project with the trench cutter in 1994. Our task was to take samples out of the alluvial soil off the coast of Namibia in a water depth of max. 200 m. We converted a drill vessel and launched the cutter thru the moon pool. The samples had a cross section of 3,40 m² and a max. depth of 5 m. They were used to estimate the content of diamonds. The first time, we reached the seabed of the deep sea was together with our seafloor exploration rig MeBo, where we can take cores up to a length of 160 m in a maximum water depth of 4000 m. With our customer MARUM, we have done several expeditions since 2005. The last expedition took place in the Black Sea to explore gas hydrates.

Jan 1, 2018

By Raymond A. Binns

In this first sub-seafloor examination of an active hydrothermal system hosted by felsic volcanic rocks at a convergent plate margin, we drilled 13 holes altogether, achieving deep cored penetrations at two sites. Our aims were (1) to delineate the lateral and vertical variability in mineralisation and alteration patterns below the PACMANUS hydrothermal site near the 1650-1700 m-deep crest of Pual Ridge in the eastern Manus back-arc basin, so as to understand links between volcanological, structural and hydrothermal phenomena, and (2) to establish the nature and extent of microbial activity within the system. Technological innovations vital to success included our precise location of holes on small targets with drill-stem video, the use of a new hard-rock re-entry strategy, and deployment of casing with a new hammer drill. Other technical achievements were the first ODP application of an advanced diamond coring system, and the first direct comparison in a hardrock environment between structural images obtained by wireline methods and by logging-while-drilling (resistivity-at-bit).

Jan 1, 2002

By Youngtak Ko

The northeastern Pacific shows the highest nodule abundance among the oceans in the world, and thus has been drawing international attention for deep-sea manganese nodule development. The objectives of this study are to construct database using geostatistics and geographic information system (GIS), to quantify rating value using probability and statistical methods, to suggest suitable sites for manganese nodule development, and to verify results using three statistical approaches. The copper and nickel contents of the nodules were determined by chemical analysis. Factors related to slope, aspect, water depth, and topography were obtained from multi-beam echo sounding data. The transparent layer thickness was determined using a sub-bottom profiler. The probability method was used to calculate each factor's rating, and the layers for different factors were summed to produce the development potential index (DPI). Result maps were constructed for manganese nodules development. The distribution pattern of DPI showed to be controlled of nodule abundance and metal contents. Verification was performed by comparing the results with sampling data in three ways: success and prediction rate, linear regression, and test of independence.

Sep 14, 2011

By D. S. Cronan

Based on analogy with the Clarion-Clipperton zone, three main factors appear to influence the occurrence of potentially economic nodules in the study area, (i) elevated biological productivity, mainly above 50gCm-2y-l, (ii.) sea floor depth near or below the CCD, (iii) an absence of turbidite sedimentation. These conditions are fulfilled in parts of the following basins, where available data indicate that high grade and sometimes abundant nodules occur. i) The East Central Pacific Basin west of the Line Islands extending to the East Central Pacific Basin north and east of the Phoenix Islands ii) The West Central Pacific Basin west and northwest of the Phoenix Islands iii) The North Penrhyn Basin north of Penrhyn Island Notwithstanding the similarities between the environmental conditions under which potentially economic nodules occur in the Clarion-Clipperton zone and in the areas listed above, such similarities may relate only to present day conditions. During the possibly long periods of nodule formation, environmental conditions may have varied, and the deposits formed under conditions different from those prevailing at the present day. However, the fact that both present day conditions and the deposits in the two areas do show similarities suggests that applying the same genetic model to them has some validity. Possibly, any changes in environmental conditions during the period of formation of the deposits has been similar in both areas. Such uncertainties can only be resolved by a much fuller evaluation of the evolution of nodule deposits in both areas throughout recent geological time.

Jan 1, 1986

By Francois P. Leroy

In the quest of studying the assigned blocks of seafloor for deep water mining, each member country of the ISA is thirsty for accurate information as to the level of resources available. Manganese nodules represent a large portion of the resources and are as precious as they are hard to locate and harvest. Resolving such challenges is what drives the technology development and yields instruments and products capable of serving this field of research. This presentation will study how manufactures of oceanographic instruments have pushed the technology envelop to in order to transform a collection of sensors and instruments into a seamless and adapted assembly working to serve the researcher and prospector in the challenging field they operate. Deep water data collection is characterized by the following challenges: ? Deployment, recovery and handling of the vehicle ? Producing high resolution at great distances ? Positioning that data with accuracy to relocate Teledyne Marine will present the work performed in its engineering laboratories to produce sub systems and systems now capable of delivering key information necessary to the proper cataloguing and exploitation of deep water mineral mining. Understanding and controlling the alternative resources available to each country will allow better management of current traditional land based minerals.

Jan 1, 2010

By Jayne Holden

Development of a deep-sea mining system is a new and interesting field of research. Commercial mining of the ocean floor for SMS deposits is yet to occur, and while exploration of the undersea has been undertaken by various research institutes exploitation of SMS deposits is yet to be investigated in detail. Industry has been stimulated by the potential development of economically viable deep-sea mining methods. The establishment of deep-sea mining production has also been encouraged by industry trends. These include the success of the oil and offshore diamond industries, scientific advances in computer modeling, technological advances in undersea exploratory equipment and further development of the Law of the Sea. This project also presents an opportunity to build on UNSW?s established reputation, positioning the Mining Research Centre as a leader in this specialized field of research. This project aims to form a greater understanding of the environmental conditions associated with SMS deposits, detailing the physical, biological and chemical characteristics of typical ocean floor sites from an environmental management perspective. With the aid of previous numerical models and disturbance experiments that have been conducted at various ocean floor sites worldwide, new virtual reality models will be developed to enable assessment of the environmental impact of the undersea mining process. These models will simulate seafloor systems prior to mining through various stages including particle distribution and sediment disturbance, to illustrate the impact of a number of proposed mining techniques. The model will allow users an interactive virtual experience of a potential SMS deposit site where hotspots can be identified and mining processes can be demonstrated. This initial baseline model will help to establish generic parameters, which can then be modified and tailored to simulate a wide range of deposit sites and differing mining processes. These models will be validated with the development of appropriate physical modelling.

Jan 1, 2002

By Toru Yamasaki

"Bimodal lithostratigrafic assemblages are of significance in volcanogenic massive sulfide (VMS)-hosted lithology. The largest deposits are either bimodal-siliciclastic or maficsiliciclastic, and the presence of a significant siliciclastic component in the host stratigraphic succession favors large VMS deposits (e.g., Franklin et al., 2005; Barrie and Hannington, 1999). In the case of modern sub-seafloor VMS deposits in arc-related settings, the majority of deposits have been discovered in association with calderas or cauldrons (Halbach et al., 1993; Ishibashi and Urabe, 1995; Iizasa et al., 1999). These features are formed by the explosive eruption of silicic volcanoes, so that silicic host rocks and/or pumiceous volcanic clasts are generally observed around the ore deposits (e.g., Binns and Scott, 1993; Fiske et al., 2001). Caldera-like and graben-like morphological features therefore attract attention in geophysical surveys. However, silicic lithologies (dacite and rhyolite) normally contain only small amount of metallic elements (e.g., a few ppm to a few dozen ppm of Cu), whereas mafic rocks, such as basalts and basaltic andesites, contain significant amounts of metals (e.g., a few hundred ppm of Cu). Thus, the origin of metallic elements in VMS deposits associate with the silicic host rock remains unclear.The Iheya North Knoll is a volcanic complex in the middle of the Okinawa Trough. It is located in a young and actively spreading back-arc basin that extends for 1200 km behind the Ryukyu arc-trench system (Lee et al., 1980; Letouzey and Kimura, 1986). Several active hydrothermal fields have been recognized in the Iheya North Knoll. Mineralization at the Iheya North Knoll is characterized by relatively juvenile features consisting of VMS deposits with associated hydrothermal alterations to various degrees. Massive sphaleriterich sulfides at this site, recovered for the first time from beneath an active seafloor hydrothermal system, strongly resemble the black ore of the Kuroko deposits of the Miocene age in Japan (Takai et al., 2011). From February 11 to March 17, 2016, the SIP CK16-01 (Exp. 908) D/V Chikyu cruise was conducted at Iheya North Knoll and the rifting center of the Iheya Minor Ridge area, middle Okinawa Trough. The Iheya Minor Ridge area is also an active hydrothermal field, located ~30 km southeast of the Iheya North Knoll. In this area, basaltic rocks are widely distributed, and drilling has confirmed that the basaltic materials continue to ~120 m below the seafloor (Kumagai et al., in prep)."

Jan 1, 2017

By Pedro Madureira, Georgy Cherkashov, Harald Brekke, Marzia Rovere

"The most promising deep-sea mineral resources for exploration in the Area (beyond the limits of national jurisdiction) are polymetallic nodules, cobalt-rich ferromanganese crusts and polymetallic sulphides. These marine minerals have different characteristics in their distribution, geological setting, grades of metals and genesis. Considering future exploitation of nodules, crusts and sulphides such parameters as estimated resources, specific mining operations and ore processing are different as well.Comparative analyses of deep-sea mineral minerals as well as onshore and offshore resources will be discussed in the paper."

Jan 1, 2017

By M. Ravindran

The Government of India started its deep seabed exploration programme during 1982. This programme was started as one of national importance and several national laboratories were involved to realize the development of requisite technologies for deepsea mining and processing. After a concentrated effort on surveying, using its own as well as hired ships, India succeeded by mid 1980s in identifying a prospective site in the Indian Ocean as an exclusive claim for development. India was registered as a Pioneer Investor and became the first country to obtain this status on 17th August 1987. India has been allocated an exclusive mine site of 150,000 km2 in the Central Indian Ocean. Our country also developed considerable expertise in the metallurgical processing for extracting metals from these nodules. The Department of Ocean Development, Government of India, the organization which is designated as the nodal agency responsible for implementing the deep seabed mining programme has drawn up a long term plan which will enable it to fulfill its obligations as a Pioneer Investor. The work toward the design and development of a mining system has been entrusted to the Central Mechanical and Engineering Research Institute, Durgapur. As a part of this programme they have developed a nodule collector and a riser system which have been tested in very shallow waters only. Since this technology development for deep sea mining applications is highly time consuming and very expensive, this programme is also being used to develop components for intermediate applications. In view of the long timeframe required for perfecting a deepsea nodule mining technology, the Government of India is also keen on developing shallow water mining systems for utilizing the placer deposits. One of the richest heavy mineral deposits in the Indian Exclusive Economic Zone is available on the west coast of South India in the state of Kerala. The coastal stretch between Kanyakumari, on the southern tip of India, and Alleppey along the west coast at a distance from the tip of approximately 210 km, there is a good multimineral reserve. The initial survey indicates that the estimated reserves in the surveyed areas are approximately as follows: Ilmenite 1.4 million tonnes Rutile 0.14 million tomes Zircon 0.13 million tomes Sillimanite 0.53 million tonnes

Jan 1, 1994

By Kris De Bruyne

Since 2013, GSR has undertaken 4 exploration campaigns, which focused on environmental baseline monitoring (marine biology), resource definition and technological change. The seabed nodule collection vehicle has a significant influence on the achievable production rate and is for that reason thought to be a serious risk in developing an economical viable mining operation. GSR is currently working on a pre-prototype of a seabed nodule collection vehicle. The program, called ProCat, started in 2015 and will take up to end of 2019. ProCat can be split up in 2 phases: ‐ ProCat#1 [2015 – Q2 2017]: separate parallel testing of the nodule collection- and driving mechanism (Tracked Soil Testing Device Patania I – TSTD Patania I). The trafficability was tested in-situ; the collection mechanism was tested in a laboratory. Phase 1 has been completed successfully in September 2017. ‐ ProCat#2 [Q3 2017 – end of 2019]: the knowledge acquired during the first phase was used in this 2nd phase. Both collection mechanism and driving mechanism were integrated into the design of a pre-prototype seabed nodule collection vehicle (Pre-Prototype Vehicle Patania II – PPV Patania II). This pre-prototype vehicle will be used for a simulated mining test in Q2 of 2019 in the GSR- and BGR license area. The main objective of the ProCat research program, and especially the 2nd phase, is to integrate the nodule collector on the tracked chassis and develop an operating vehicle causing minimal environmental impact hereby validating the requirements for a full scale polymetallic nodule collection vehicle in the actual operational environment of the CCFZ. Following the ProCat project, GSR is working towards a system-integrated mining test once exploitation regulations have been agreed by the ISA and its member States.

Jan 1, 2018

By Marlene Olivares Cruz

The particles that make up the deep-sea sediments have two main sources: 1) those that are created in situ from dissolved components and 2) those that are washed into the ocean in solid phases from the continents, atmosphere, space and interior of the Earth. Many particles as they sink through the water column reaches the seabed and are known as pelagic sediments with terrigenous, biogenic, authigenic, and cosmogenic components. Among the minerals found in the terrigenous fraction of pelagic sediments are quartz, clay minerals, feldspar, micas, ferromagnesians, and the biogenic fraction with remains of siliceous organisms, such as, radiolarian and diatoms. The chemical nature of marine sediments is controlled by the contribution of particulate matter derived from various sources with varying compositions for the fixing of elements during deposition and the compositional changes carried out within the sediments during diagenesis. In the last decade there have been several studies on the mineralogical composition of seabed sediments, suspended particulate materials and cores, together with paleontological and geochemical data are used for paleoclimatic and paleoenvironmental reconstructions, analyze changes in sea level, stratigraphic correlations and identify past and

Sep 14, 2011

By J. W. Jamieson

"The future of the marine mining industry is tied to the resource potential of the seafloor. Everything from economic feasibility, policy decisions and environmental impact assessments to extraction techniques and mining tool design rely on an understanding of the size, composition, and distribution of the deposits. Development and regulatory decisions must ultimately be tied to not only the grade and tonnage estimates of individual deposits or groups of deposits, but also an understanding of the uncertainty of these estimates. Here, we will discuss how seafloor massive sulfide (SMS) deposit grades and tonnages are evaluated, and the sources of the uncertainties associated with these values.TONNAGE UNCERTAINTYFirst-order tonnage (size) estimates for SMS deposits are primarily determined from calculating the volumes of material that occurs as positive bathymetric features on the seafloor. The extent of sulfide mineralization on the seafloor can be determined either from visual surveys (camera-tow, remotely-operated vehicle (ROV), or human-occupied submersible surveys) or from volume calculations of bathymetric features identified from digital elevation models of the seafloor, or a combination of both methods. For bathymetric models to be used to identify deposits in the absence of visual groundtruthing, data resolution of 1 m or less is generally required to confidently identify a feature as being hydrothermal in origin (as opposed to a volcanic or tectonic feature), and therefore near-bottom multibeam data acquisition (e.g., using autonomous underwater vehicle (AUVs) or remotely operated vehicles (ROVs) is required (Fig. 1). Specific characteristics of bathymetric features, such as shape, slope angles and surface roughness can be used to identify features of hydrothermal origin (Fig. 1). However, so far, bathymetric features mapped at a resolution of ~1 m cannot be relied upon to unambiguously distinguish a sulfide mound, and the additional use of multiple AUVmounted sensors, such as magnetometers, which can be used to detect hydrothermal upflow zones, or self-potential sensors, which detect electrical fields related to the oxidation of sulfide minerals, can increase the confidence that a bathymetric feature is indeed a sulfide body, without the need for expensive and time-consuming visual surveys (c.f. Petersen et al., this volume)."

Jan 1, 2017

By J. R. Woolsey

Research grants of The Marine Minerals Technology Center (MMTC) are directed toward development of the technology 'for exploration, mining, and processing of non-fuel mineral resources within the U.S. Exclusive Economic Zone. FY 1989-90 research grants are as follows: - Seafloor Gamma Measurement Data Collection System. - Free-Fall Seafloor Hard Substrate Corer. - Microtopography of Manganese Crust Deposits. - Cobalt Crust Continuum on Seamounts, EEZ, Hawaii. - Economics of Marine Polymetallic Sulfide Resources. - Graphite Furnace Atomic Absorption Spectrometer. - Depositional Models for Aggregate and Heavy Mineral Exploration. - Sand Resources of Heald and Sabine Banks, Texas. - Sources, Geometries, and Compositions of Heavy Mineral Placers. - Geostatistical Methods for Marine Placer Exploration. - Computer Aided Design for Communication and Strength Umbilicals.

Jan 1, 1989