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Harry A. Tourtelot

Publications and source records attributed to Harry A. Tourtelot.

4 recordsLinked to original sources
USGS1978

Lithium, a preliminary survey of its mineral occurrence in flint clay and related rock types in the United States

Maximum concentrations of lithium found in samples of flint clay and associated rocks of Pennsylvanian age in different States, in parts per million (ppm), are: Missouri, 5100; Pennsylvania-Maryland, 2100; Kentucky, 890; Ohio, 660; Alabama, 750; and Illinois, 160. Lithium-bearing kaolin deposits are distributed in the Coastal Plain province from New Jersey to Texas, and one occurs in Idaho; maximum lithium concentrations in samples from these deposits range from 64 to 180 ppm. The maximum concentration found in the Arkansas bauxite region is 460 ppm and that in flint clay in Colorado is 370 ppm. Samples from areas other than Pennsylvania, Maryland, Kentucky and Missouri are relatively few in number, represent mostly commercially valuable clays, and represent only a part of the refractory clay deposits in the United States. Data are not available on the clays associated with these deposits that may be unusable because they contain too much lithium as well as other deleterious elements. In both Pennsylvania and Missouri, lithium contents vary regionally between districts and locally between deposits. In samples containing more than 2000 ppm lithium, the lithium occurs in a dioctahedral chlorite mineral very similar to cookeite, which previously has not been recognized in sedimentary clays. The associated clays consist chiefly of well-crystallized kaolinite. The dioctahedral chlorite, however, seems to be most abundant where diaspore and boehmite occur along with the kaolinite. Barium, chromium, copper, phosphorus and strontium are present in some samples in amounts of several hundred pans per million or more, and may contribute to the failure of some clays to perform satisfactorily in firing tests. Lithium-rich clays could serve as a significant lithium resource in the very distant future. Clays that contain as much as 1% lithium may be common enough in Missouri or in Pennsylvania to be produced as a by-product to help support benefication costs for refractory clays. Sufficient amounts of lithium-rich clay may be found in deposits that have been explored, found unsatisfactory for normal refractory uses, and not developed. The lithium-rich clay in some deposits presently being worked may be worth stockpiling for eventual use.

Energy↗
USGS1971

Chemical compositions of rock types as factors in our environment

The types of rocks that form geologic units in the Earth’s crust supply most of the raw materials from which soils are formed and from which water derives its inorganic constituents. The compositions of what we eat and drink thus depend in part upon the compositions of the source rocks. Igneous rocks are formed by crystallization and solidification of a rock melt. Metamorphic rocks are formed by recrystallization of both igneous and sedimentary rocks caused by heat and pressure within the Earth’s crust. Sedimentary rocks are formed chiefly by the deposition in water of weathering and erosion products of pre-existing igneous, metamorphic, or other sedimentary rocks. The compositions of metamorphic rocks are generally similar to the compositions of the rocks that were metamorphosed, and only igneous and sedimentary rock compositions are considered here. Igneous rocks range in SiO 2 content from about 40 to nearly 80 percent, and other constituents increase in amount as SiO 2 decreases. The changes in the other constituents are not large, however, except for the quantitatively unimportant least silicic rocks; these contain conspicuously more magnesium and less aluminum than the other kinds of igneous rocks. Sedimentary rocks range in SiO 2 content from nearly zero for the carbonate rocks to almost 100 percent for quartzite and pure sandstone. Shale and clay contain intermediate amounts of SiO 2 and as much as 25 percent AI 2 O 3 , more than any of the igneous rocks. Carbonate rocks are composed mostly of calcium and magnesium carbonates. The contents of individual trace elements vary widely with rock type. Chromium, titanium, nickel, and cobalt are conspicuously concentrated in low-silica igneous rocks that are quantitatively unimportant. Arsenic, iodine, molybdenum, and selenium are conspicuously concentrated in shale and clay. In addition, most other elements occur in largest amounts in shale and clay compared to other sedimentary rocks, and in amounts nearly equal to those in igneous rocks. Soils derived from different kinds of igneous rocks do not differ from each other as much as do soils derived from different kinds of sedimentary rocks. This is partly because igneous rocks generally are more resistant to weathering than sedimentary rocks that were deposited in water. Some of the important constituents of sedimentary rocks have been precipitated from solution, which makes them more susceptible to weathering and re-solution. Similarly, sedimentary rocks have a greater effect than igneous rocks on the composition of ground water. Determination of areal variations in composition should be more detailed than normal petrologic investigations if the results are to be usable for environmental studies. Statistical principles should be used in planning the sampling, analysis, and interpretation of results.

Book chapter↗
USGS1955

Radioactivity and uranium content of some Cretaceous shales, central Great Plains

The Sharon Springs member of the Pierre shale of Cretaceous age, a hard black organic-rich shale similar to the Chattanooga shale, is radioactive throughout central and western South Dakota, most of Nebraska, northern Kansas, and northeastern Colorado. In the Missouri River valley, thin beds of the shale contain as much as 0.01 percent uranium. Beds as much as 20 feet thick or more have a radioactivity of about 0.01 percent equivalent uranium in southwestern Nebraska according to interpretation of gamma-ray well logs. The radioactivity and uranium content is highest in the Missouri River valley in South Dakota and in southwestern Nebraska where the shale rests disconformably on the underlying Niobrara formation of Cretaceous age. Near the Black Hills, and in the area to the north, the shale of the Sharon Springs member rests on a wedge of the Gammon ferruginous member of the Pierre, which is represented by a disonformity to the east and south, and the radioactivity of the shale is low although greater than that of over-lying strata. The shale also contains a suite of trace elements in which arsenic, boron, chromium, copper, molybdenum, nickel, selenium, and vanadium are conspicuous. Molybdenum and tin are less abundant in the Sharon Springs than in similar shales of Palezoic age and silver and selenium are more abundant. In the Great Plains region, the upper 30-50 feet of Cretaceous shales overlain unconformably by the White River group of Oligocene age has been altered to bright-colored material. This altered zone is chiefly the result of pre-Oligocene weathering although post-Oligocene ground water conditions also have affected the zone. The greatest radioactivity occurs in masses of unaltered shale measuring about 1 x 4 feet in cross section included in the lower part of the altered zone. Where the zone is developed on shale and marl of the Niobrara formation, parts of the included unaltered shale contains as much as 0.1 percent equivalent uranium and 0.03 percent uranium. The disequalibrium between equivalent uranium (radioactivity) and the uranium content of the shales is believed to be a surface feature caused by relatively recent leaching of uranium from the present outcrops. The co-extensive distribution of the altered zone of Cretaceous shales and strata of the overlying White River group suggest that most of the uranium in the small masses of unaltered marl in the altered zone has been derived from the White River group.

Colorado;Kansas;Nebraska;Wyoming↗