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Richard Porter Sheldon

Publications and source records attributed to Richard Porter Sheldon.

18 recordsLinked to original sources
USGS1985

Undiscovered phosphate resources in the Caribbean region and their potential value for agricultural development

The countries of the world's humid tropical regions lack the soil fertility necessary for high agricultural productivity. A recently developed agricultural technology that increases soil fertility can make tropical agriculture highly productive, but the technique requires large inputs into the soil of phosphorus and other fertilizers and soil amendments. Use of fertilizers derived from phosphate rock is increasing greatly throughout the world, and fertilizer raw materials are being produced more and more frequently from phosphate rock deposits close to the areas of use. An increased understanding of the origin of phosphate rock in ancient oceans has enabled exploration geologists to target areas of potential mineral resource value and to search directly for deposits. However, because of the difficulty of prospecting for mineral deposits in forested tropical regions, phosphate rock deposits are not being explored for in the countries of the humid tropics, including most countries of the Caribbean region. As a result, the countries of the Caribbean must import phosphate rock or phosphorus fertilizer products. In the present trade market, imports of phosphate are too low for the initiation of new agricultural technology in the Caribbean and Central American region. A newly proposed program of discovery and development of undiscovered phosphate rock deposits revolves around reconnaissance studies, prospecting by core drilling, and analysis of bulk samples. The program should increase the chance of discovering economic phosphate rock deposits. The search for and evaluation of phosphate rock resources in the countries of the Caribbean region would take about 5 years and cost an average of $15 million per country. The program is designed to begin with high risk-low cost steps and end with low risk-high cost steps. A successful program could improve the foreign exchange positions of countries in the Caribbean region by adding earnings from agricultural product exports and by substituting domestically produced phosphate rock and fertilizer products for imported phosphate fertilizers. A successful program also could provide enough domestically produced phosphorus fertilizer products to allow initiation of new agricultural technology in the region and thus increase domestic food production. Finally, a new phosphorus fertilizer industry would create new jobs in the mining, chemical, and transportation industries of the Caribbean region.

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USGS1984

Phosphate rock resources of the United States

In 1980, the United States produced about 54 million tons of phosphate rock, or about 40 percent of the world's production, of which a substantial amount was exported, both as phosphate rock and as chemical fertilizer. During the last decade, predictions have been made that easily ruinable, low-cost reserves of phosphate rock would be exhausted, and that by the end of this century, instead of being a major exporter of phosphate rock, the United States might become a net importer. Most analysts today, however, think that exports will indeed decline in the next one or two decades, but that resources of phosphate are sufficient to supply domestic needs for a long time into the future. What will happen in the future depends on the actual availability of low-cost phosphate rock reserves in the United States and in the world. A realistic understanding of future phosphate rock reserves is dependent on an accurate assessment, now, of national phosphate rock resources. Many different estimates of resources exist; none of them alike. The detailed analysis of past resource estimates presented in this report indicates that the estimates differ more in what is being estimated than in how much is thought to exist. The phosphate rock resource classification used herein is based on the two fundamental aspects of a mineral resource(l) the degree of certainty of existence and (2) the feasibility of economic recovery. The comparison of past estimates (including all available company data), combined with the writers' personal knowledge, indicates that 17 billion metric tons of identified, recoverable phosphate rock exist in the United States, of which about 7 billion metric tons are thought to be economic or marginally economic. The remaining 10 billion metric tons, mostly in the Northwestern phosphate district of Idaho, are considered to be subeconomic, ruinable when some increase in the price of phosphate occurs. More than 16 billion metric tons probably exist in the southeastern Coastal Plain phosphate province, principally in Florida and North Carolina and offshore in the shallow Atlantic Ocean from North Carolina to southern Florida. This resource is considered to be hypothetical because it is based on geologic inference combined with sparse drilling data. Total resources of phosphate rock in the United States are sufficient to supply domestic demands for the foreseeable future, provided that drilling is done to confirm hypothetical resources and the chemistry of the deposits is determined. Mining and beneficiation techniques will have to be modified or improved, and new techniques will have to be developed so that these deposits can be profitably exploited.

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USGS1981

A summary of phosphate-rock resources of the United States-an analysis of past estimates

The United States produced in 1980 about 54 million tons of phosphate rock, which was 40 percent of the world production. About 62 percent of this production was exported, 28 percent as phosphate rock and 34 percent is manufactured fertilizers and chemicals. The remainder was used domestically, largely (88 percent) for fertilizer and animal feed supplement to produce agricultural products (U.S. Bureau of Mines, 1981). A significant portion of these agricultural products was exported, so the phosphate rock that went into that portion was exported indirectly. Thus, most phosphate production is exported directly or indirectly and contributes to the U.S. balance of international payments. Although the marketable value of the phosphate rock produced in 1980 was only about $1.2 billion, the total value of the agricultural and chemical products depending on phosphate rock input is many times that. The continued ability of the U.S. phosphate industry to supply low-cost phosphate rock for export and domestic consumption is clearly of major importance to the Nation.

Open-File Report↗
USGS1967

Discovery of phosphate rock in Saudi Arabia and recommended program of further study

In the period August 12, to September 3, 1965, I was assigned as a phosphate specialist to the U.S. Geological Survey Group in Saudi Arabia to work in cooperation with the Ministry of Petroleum and Mineral Resources of the Saudi Arabian Government. My assignment was to evaluate the phosphate potential of Saudi Arabia, train a Saudi Arabian geologist counterpart in modern techniques of phosphate exploration, and to help set up a program of exploration. These objectives have been largely fulfilled. In addition phosphate rock was discovered.

Open-File Report↗
USGS1953

Stratigraphic sections of the Phosphoria formation in Wyoming, 1951

The U.S. Geological Survey has recently measured and sampled the Phosphoria formation at many localities in Wyoming and adjacent states. These data will not be fully synthesized for many years, but segments of the data, accompanied by little or no interpretation, are published as preliminary reports as they are assembled. This report, which contains abstracts of the sections measured in western Wyoming (fig. 1) during 1951, is the third Wyoming report of this series. The field and laboratory procedures adopted in these investigations are described rather fully in a previous report (McKelvey and others, 1953b). Many people have taken part in this investigation. J. W. Hill, H. W. Peirce, J. A. Peterson, and R. A. Smart participated in the description of strata and the collection of samples referred to in this report. The laboratory preparation of samples for chemical analysis was done in Denver, Colo., under the direction of W. P. Huleatt.

Wyoming↗
USGS1952

The Permian phosphorite deposits of western United States

The Permian marine phosphorite deposits of the western United States were laid down in the Phosphoria formation and its partial stratigraphic equivalents over an area of about 135,000 square miles in Montana, Idaho, Wyoming, Utah, and Nevada. The deposits in the eastern part of the field lie on the western margin of the structurally simple North American craton. The rocks there consist of a few thin, locally glauconitic, nodular phosphorites, generally containing less than 30 percent P 2 0 5 , interbedded with nodular limestones, calcareous mudstones, and sandstones. Eastward these marine beds tongue out into continental redbeds. The deposits in the western part of the field are a part of the complexly folded Cordilleran miogeosyncline. The facies there are of a deeper-water type and include thick phosphorite layers containing as much as 35 percent P 2 0 5 b lack phosphatic mudstones, limestones, and well-bedded black cherts. The phosphorite deposits are composed chiefly of colloform carbonate-fluorapatite, quartz, and clay. In addition to phosphorus, they contain several minor elements that are of potential economic interest. The most important of these are fluorine, vanadium, chromium, nickel, rare earths, zinc, and uranium.

Open-File Report↗