Geological survey

Important ore deposits are found in Zaire, Morocco, and Ganada. The U.S. Geological Survey has announced that the bottom of the north central Pacific Ocean may have cobalt-rich deposits at relatively shallow depths in water close to the the Hawaiian Islands and other U.S. Pacific territories. 

J. J. Eahey, Saline Minerals of the Green PiverFormation, Geological Survey Professional Paper 405, U.S. Government Printing Office, Washington D.C., 1962. 

B. H. Baker, Geology of the Magadi Area, Geological Survey of Kenya, Report 42. 

E. A. Imhoff, U.S. Geological Survey Open File Report No. 76-648, U.S. Government Printing Office, Washington, D. C., 1976. 

R. H. Shiley, D. R. Dickerson, and G. C. Finger, Aromatic Fluorine Chemisty at the Illinois State Geological Survey, circular 501, Urbana, lU., 1978. 

The importance of a coal deposit depends on the amount that is economically recoverable by conventional mining techniques. The world total recoverable reserves of lignitic coals were 3.28 x 10 metric tons at the end of 1990 (3), of which ca 47% was economically recoverable as of 1994 (Table 4). These estimates of reserves change as geological survey data improve and as the resources are developed. 

Detailed information concerning the location and analysis of limestone deposits in the United States can be obtained from the various state geological surveys, the U.S. Bureau of Mines, and the U.S. Geological Survey. Descriptive summaries of the limestone deposits in the various states have beenpubhshed (5,6). 

Demonstrated reserve quantities are estabUshed by measurements including drillings surface sampling, etc. Inferred reserves are those derived from geological survey information, not by measurement of the extent of the particular reserve. Not included herein are identified marginal and speculative resources, such as the oil-field and geothermal brines and lithium-hearing clays. These latter reserves are speculative as to extent, not existence. Total undiscovered clays in the western United States are speculatively estimated at 15 x 10 t lithium (16). More detailed Hsts of reserves are also available (15,17). 

Analytical standards imply the existence of a reference material and a recommended test method. Analytical standards other than for fine chemicals and for the NIST series of SRMs have been reviewed (6). Another sphere of activity ia analytical standards is the geochemical reference standards maintained by the U.S. Geological Survey and by analogous groups ia France, Canada, Japan, South Africa, and Germany (7). 

V. E. McKelvey and co-workers. Subsea Mineral Resources, Bulletin 1689-A, U.S. Geological Survey, Woods Hole, Mass., 1986. 

Interior Department Interior land management, fish and wildlife. Geological Survey, mines, surface mining and reclamation... 

Natural Deposits. Natural deposits, eg, minerals and fossil fuels, are located by drilling operations. An auger, eg, a screw or worm, is turned in the earth and pulled out, and material is scraped from the auger for analysis. Alternatively, samples can be taken by hoUow core drills which, when withdrawn, enclose a core of the earth that is representative of the strata through which the drill has passed. Such core samples are used in geological surveys for fossil fuels. As the drill drives deeper into the strata, each core is extracted and placed in a shallow box and coded so that a complete cross section of the geological strata can be reconstmcted. From this, the relative thickness of coal and mineral seams can be directly measured. 

P. H. Price, C. E. Hare, J. B. McCue, and H. A. Hoskins, Salt Trines of West Wirginia, West Virginia Geological Survey, Morgantown, W. Va., 1937. 

GrossHng and G. E. Ericksen, Computer Studies of the Composition of Chilean Nitrates Ores, U.S. Geological Survey, Washington, D.C., Dec. 1970. 

According to statistics collected by the U.S. Geological Survey (3), U.S. production of cmde talc in 1995 was 1,050,000 metric tons. Montana, Texas, Vermont, and New York were the principal producing U.S. states. Worldwide production was estimated to be 5,845,000 t. China, having 2,400,000 t, was the largest producer in the world after China and the United States, Finland, India, Brazil, France, Italy, and Canada are the next principal producers. World production of talc in 1994 is Hsted in Table 1. 

The market for talc in the United States based on the 1995 U.S. Geological Survey Annual Review (3) is summarized in Table 2. Ceramics was the biggest market, having almost 35% of the total, followed by paint, paper, and plastics. Outside of the United States, especially in Asia, paper is the principal apphcation. In that region talc is available locally at lower cost than competitive minerals such as kaolin. 

R. Towner,. Gray, and L. Porter, International Strategic Minerals Inventory Summary Report—Titanium., U.S. Geological Survey Circular 930-G, 1989. 

Mineral Commodity Summaries, Department of the Interior Geological Survey and Bureau of Mines, Washington, D.C., 1996. 

Ref. 2. Derived in collaboration with the U.S. Geological Survey. Data may not add to totals shown because of independent rounding. ... 

Geological Survey, New York District office written communication, 1991. ... 

Fig. 2. Annual sulfate yields of the St. Lawrence River at Cornwall, Ontario, Canada, 1906—1990. (Calculated from data in U.S. Geological Survey...

R. A. Smith, R. B. Alexander, and M. G. SdJo m.2ia,yinaljsis and Interpretation of Water-Quality Trends in MajorU.S. Rivers, 1974—81, U.S. Geological Survey Water-Supply Paper 2307, U.S. Geological Survey, Reston, Va., 1987. 

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