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Geology topics

Frank T. Manheim

Publications and source records attributed to Frank T. Manheim.

At least 37 records · Page 2Linked to original sources

Mineral resources of the U.S. Atlantic continental margin

Most geologic materials may be usable resources in some form and at some time, whether it be for general land fill and aggregate, beach replenishment, construction material, or as a source of metals and fuels. Thus, most natural materials occurring within the Atlantic continental margin are resources, defined as “materials, including those only surmised to exist, that have present or anticipated future value” (U.S.G.S., 1980). Whether a resource becomes a reserve or not (an economically recoverable commodity) depends upon the properties and economic values of that material, which are determined by the following factors: (a) availability, concentration, and occurrence of the material; (b) methods of recovering and processing the commodity; (c) transportation costs of ore and beneficiated products; and (d) environmental setting and costs of permitting and mitigation. Also, the economics of a given mineral resource change dramatically in response to new technological advances, discoveries of new deposits, or as industrial and social demands change through time. An increasingly critical component associated with the economics for development of any mineral commodity, is a good geologic knowledge of the resource base.

Atlantic Continental Margin

Resource potential of the western North Atlantic Basin

We here consider the petroleum resources only of the off shelf portion of the western North Atlantic Ocean. Very little information is available for this region; off the eastern United States, only four petroleum exploration holes have been drilled in one restricted area seaward of the shelf, off the Baltimore Canyon trough. However, by interpreting seismic reflection profiles and Stratigraphie data from the Deep Sea Drilling Project (DSDP) and other wells on the adjacent slope and shelf, we can evaluate the geologic conditions that existed during development of the basin and that might lead to petroleum accumulations. The wellknown factors that lead to oil and gas accumulations are availability of source beds, adequate maturation, and the presence of reservoir beds and seals configured to create a trap. The western boundary of the area considered in this paper, the present sloperise break, is one that has developed from the interplay of sedimentation and erosion at the continental margin; these processes are affected by variations in margin subsidence, sedi-ment input, oceanic circulation, sea level, and other factors. Thus the sloperise break has migrated over time and is locally underlain by slope and shelf deposits, as well as deepbasin facies. These changes in depositional environments may well have caused juxtaposition of source and reservoir beds with effective seals.

Book chapter

Determination of interstitial chloride in shales and consolidated rocks by a precision leaching technique

We have devised a technique for determining chloride in interstitial water of consolidated rocks. Samples of rocks ranging from 5 to 10 g are crushed and sieved under controlled conditions and then ground with distilled water to submicron size in a closed mechanical mill. After ultra-centrifugation, chloride content is determined by coulometric titration. The chloride concentrations and total pore-water concentrations, obtained earlier from the same pore-water concentrations, obtained earlier from the same samples by low-temperature vacuum desiccation, are used to arrive at the "original" pore-water chloride concentrations by a simple iteration procedure. Interstitial chlorinity results obtained from Cretaceous and Jurassic strata in the Gulf of Mexico coastal areas ranged from 20 to 100 g/kg Cl with reproducibility approaching +/- 1%. We have also applied the technique to igneous and metamorphic bedrocks as well as ocean basalts containing 1 % water or less. Chloride values ranging from 6.7 to 20 g/kg with a reproducibility of about 5% were obtained.

Society of Petroleum Engineers journal

An extensive data base for cobalt-rich ferromanganese crusts from the world oceans

A new database for ferromanganese crusts from the world oceans is being compiled by the U.S. Geological Survey. Crusts differ from abyssal nodules by forming principally on steeper, raised areas or current-swept plateaus in the oceans. Some crusts contain relatively large concentrations of cobalt (1.0%) in areas within national territorial jurisdictions.

Conference Paper

Hard mineral resources around the U.S continental margin

The territorial waters surrounding the United States contain vast quantities of hard mineral resources. Some, such as sand and gravel in the New York Bight, Beaufort Sea, portions of southern California, and submerged lands near Hawaii are relatively well known and characterized by local need and immediate mining potential with available technology. Commoditie of interest to industry and having nearterm economic potential that might require new or innovative technology, inlcude phosphorites such as those in the south eastern Atlantic margin, and manganese nodules on the Blake Plateau (which have potential for catalyst material, manganese, cobalt, nickel, and platinum). Commodities having significant potential, but which are poorly known and which may require innovative recovery technology, include chrome, gold, platinum, and tin placer deposits, with special emphasis on the continental margins of northern California, Oregon, Washington, and Alaska; rock salt and evaporite minerals in the Gulf of Mexico and Atlantic; titanium and other heavy minerals in the Atlantic continental margin, and calcium carbonate. A. U.S. Department of the Interior moratorium on offshore leasing in federal waters has existed since 1968. Leasing and regulatory systems will be required to begin commercial mining or intensive exploration of the above resources

Conference Paper

Composition and origin of phosphorite deposits of the Blake Plateau

An area of about 22 000 km 2 on the N Blake Plateau contains an estimated 2 billion tonnes of phosphorite concretions, and about 1.2 billion tonnes of mixed ferromanganese-phosphorite pavement. The phosphorite consists primarily of carbonate-fluorapatite, some calcite, minor quartz and other minerals. Drilling and other evidence show that the phosphorite is a lag derived from Miocene strata correlatable with phosphatic M Tertiary sediments on the continent. It has undergone variable cycles of erosion, reworking, partial dissolution and reprecipitation. Its present form varies from phosphatized carbonate debris, loose pellets, and pebbles, to continuous pavements, plates, and conglomeratic boulders. No primary phosphatization is currently taking place on the Blake Plateau.

Blake Plateau