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S. H. Patterson

Publications and source records attributed to S. H. Patterson.

10 recordsLinked to original sources
USGS2024

Imogolite and allophane formed in saprolite of basalt on Maui, Hawaii

Inorganic gel and allophane collected from basaltic saprolite on Maul, Hawaii, and studied by Patterson in I964 were reexamined. The main constituent of the gel is imogolite, and gibbsite and allophane are the minor constituents. Electron and X-ray diffraction patterns, DTA curve, and an infrared spectrum of the gel are characteristic of imogolite. The allophane is virtually noncrystalline to X-rays but contains a small amount of imogolite in relatively short threads. High-resolution electron micrographs indicate differences in structural organization between allophane and imogolite and suggest crystallization of imogolite from allophane. The occurrence of imogolite as a weathering product has been reported in many localities from pyroclastic materials but not from massive rocks. Probably the exceptionally high rainfall, excellent subsurface permeability of the weathered material, and the low pH and high organic content of the leaching solution provide favorable conditions for formation of imogolite from basalt on Maul.

Hawaii↗
USGS1979

Geology and industrial mineral resources of the Macon-Gordon kaolin district, Georgia

The Macon-Gordon kaolin district is about 80 miles (130 km) southeast of Atlanta, Georgia. It extends across the boundary between, and includes parts of, the Piedmont and Atlantic Coastal Plain physiographic provinces. The rocks in the Piedmont are mainly intensely folded sericite schist and granite gneiss containing irregular masses of amphibolite and feldspathic biotite gneiss and scattered igneous intrusive rocks. Most of the crystalline rocks are thought to be of Paleozoic age, but some of the intrusive rocks may be younger. The crystalline rocks are cut by a major unconformity and are overlain by sedimentary formations ranging in age from Cretaceous to Miocene. The valuable kaolin deposits occur in the Cretaceous beds, undivided, and in the Huber Formation which is of Paleocene to middle Eocene age. The resources of kaolin in the district are estimated in millions of metric tons as follows: reserves, 100; subeconomic resources, 700 to 900; undiscovered resources, probably 700 to 1,000. In addition to kaolin, the leading mineral commodity mined in the district, crushed stone and sand are now being produced, and fuller's earth and a minor amount of limestone were formerly produced. The crushed stone is quarried from igneous rocks in the Piedmont province. The sand is washed from the Cretaceous beds, undivided. The fuller's earth was mined from the Twiggs Clay Member of the Barnwell Formation, and limestone was dug from the Tivola Limestone.

Georgia↗
USGS1961

Origin of Pennsylvanian underclay and related seat rocks

Seat rocks, including underclay, underlie coal beds and show features such as roots, profiles similar to water-logged soils, lack of bedding, soil-like fracture, and gradation into normally bedded sedimentary rocks indicating that they were once soils. Coarse-grained seat rocks range from argillaceous to nearly pure quartz sandstone (ganister). Seat rocks composed of clay-sized particles (underclays) range from mixtures of illite, mixed-layer clay, and kaolinite to essentially pure kaolinite. Variations in the quartz or kaolinite content suggest that there are degrees of alteration in the formation of a seat rock and that all kinds of seat rock were formed by leaching of the substratum in a swamp. The increasing crystallinity of the clay minerals from plastic underclays to semiflint clay to flint clay and the corresponding increase in titanium support this conclusion. These two features suggest strongly that flint clays formed in place in an acidic swamp environment. The Olive Hill clay shows residual acidity. Seat rocks are affected by the chemical environments in the swamp before peat accumulation, during peat accumulation, and during coalification. Kaolinite is forming in present-day swamps and in wet acidic soils in Hawaii and probably formed in late Paleozoic swamps. The facts can be interpreted to show that all kinds of seat rocks could have formed in Pennsylvanian swamps and probably most did.

Geological Society of America Bulletin↗