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Walter S. White

Publications and source records attributed to Walter S. White.

13 recordsLinked to original sources

Cleavage in east‐central Vermont

Two types of cleavage, schistosity (flow cleavage) and slip cleavage, are common in the metamorphosed sediments of east‐central Vermont. Two generations of cleavage are also recognized. Cleavage of the earlier stage of deformation is schistosity, and is generally parallel to bedding. Just west of the Monroe Fault, along the eastern border of the area, only this earlier schistosity is present; farther west, a slip cleavage cuts the earlier schistosity. This slip cleavage is more and more intensely developed toward the west, and about three or four miles west of the Monroe Fault it grades without deflection into a true schistosity. This later schistosity apparently has obliterated the earlier schistosity that is presumed to have been present here. Both the later schistosity and its more easterly equivalent, the slip cleavage, are parallel to the axial planes of numerous minor folds in the rocks. The passage without deflection of slip cleavage into schistosity is taken as evidence that slip cleavage and schistosity are here mechanically equivalent. Schistosity forms in the higher metamorphic environment (staurolite zone of metamorphism in this area).

Vermont

Geologic maps : Portraits of the Earth

The picture above is a portrait of many square miles of the Earth's surface. The purpose of this leaflet is to explain how this portrait was made, how it can tell us about what lies beneath the surface of the ground, and other ways in which it can be useful to mankind.

General Information Product

A theoretical basis for exploration for native copper in northern Wisconsin

Exploration for native copper in the Keweenawan lavas of northern Wisconsin has been concentrated in areas of relatively shallow overburden that have sparse to numerous outcrops. Lack of success of this exploration suggests that if large deposits, comparable to those of northern Michigan, are present, they are more likely to be found in one or more of the large tracts that have few, if any, exposures, away from the ' copper ranges. ' A hydrologic model that may explain the mineralization of the classic native-copper district of Michigan could be helpful in suggesting that certain covered tracts are more favorable than others, and in narrowing the targets for physical exploration within these tracts. This model involves updip migration of a hydrothermal fluid of metamorphic origin, formed when ground water contained in the interstices of lava flows and conglomerate beds was carried to great depth along the axis of the Lake Superior syncline. The largest reservoirs of such buried ground water would be expected in the peripheral rather than central parts of the basins in which the lavas originally accumulated because the ratio of porous fragmental flow tops and conglomerate beds to massive basalt should increase towards the margins of a basin. Thus, the areas most promising for copper deposits should be those updip from places where the trough of the later formed Lake Superior syncline crosses the marginal parts of a lava basin. (Woodard-USGS)

Circular

A paleohydrologic model for mineralization of the White Pine copper deposit, northern Michigan

Pertinent physical properties of the upper Keweenawan rocks can be measured or inferred within a sufficiently narrow range to make the quantitative evaluation of various paleohydrologic models for the origin of the White Pine copper deposit feasible. The approach is illustrated here by calculations for models that involve lateral migration of fluids through the subjacent Copper Harbor Conglomerate to the site of the deposit and stripping of copper from these solutions where they percolated upward through the Nonesuch Shale. The calculations reveal limitations to theories of origin that would not be evident from purely qualitative consideration; some of these limitations could be useful to exploration. For example, if the water was yielded by compaction of the Copper Harbor Conglomerate and contained 50 ppm Cu, there must have been significant convergence of solution paths toward White Pine. Surface water entering the Copper Harbor Conglomerate on the north limb of the Lake Superior syncline is an adequate source if it could be shown that the point of entry was once significantly higher in altitude than the water table at White Pine; this model implies a major copper deposit at great depth north of the axis of the syncline. Ground water entering the Nonesuch Shale up dip from White Pine is not a possible source of mineralizing solutions.

Michigan

Stratigraphic sections at White Pine copper mine, Ontonagon County, Michigan

The lithology and stratigraphy of the ore zones near the base of the Nonesuch formation in the vicinity of the White Pine copper mine, Ontonagon County, Michigan, are shown on preliminary stratigraphic sections that have been made available for examination. Partial logs of 91 holes, drilled by the Copper Range Company from 1937 to 1949 in an area of approximately 9 square miles, are graphically presented on 15 sheets. The stratigraphic sections, at vertical scale of 1 inch equals 4 feet, show lithologic details of composition, bedding, and color, in the lower 60 feet of the Nonesuch formation and in the top of the immediately underlying rocks. The stratigraphic sections of 7 drill holes long the line of the main service drift now being driven to develop the White Pine mine have copper assays (from records of the Copper Range Company) correlated with the lithology. These assays are representative of the area, and they illustrate the stratigraphic restriction of the ore and the persistent correlation between lithology and copper content. This open-file material, entitled "Stratigraphic sections at White Pine, Ontonagon County, Michigan", records the lithologic end stratigraphic classification of these drill cores by W. S. White end J. C. Wright, end copies are available for examination in the offices of the Geological Survey: Room 1033 (Library), General Services Administration Washington, D. C.; Room 213 Science Hall, University of Wisconsin, Madison 6, Wisconsin; and Calumet, Michigan; and at the office of the Geological Survey Division, Michigan Department of Conservation, Lansing, Michigan.

Michigan

A cotangent ruler for simplifying the graphic solution of problems in structural geology

The cotangent ruler is a device for measuring directly the dip of contoured surfaces, or, conversely, for constructing contours that represent planes of known dip. It greatly simplifies the graphic solution of problems in structural geology, and has several specialized applications to problems commonly encountered in mining geology and areal geologic mapping.

Economic Geology