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Research about Michigan, Wisconsin

Source-linked reports with geographic coverage including Michigan, Wisconsin.

At least 91 records · Page 5Linked to original sources
USGS1983

Mineral resource assessment of the Iron River 1° x 2° quadrangle, Michigan and Wisconsin

The Iron River 1? x 2? quadrangle contains identified resources of copper and iron. Copper-rich shale beds in the north part of the quadrangle contain 12.2 billion pounds (5.5 billion kilograms) of copper in well-studied deposits including 9.2 billion pounds (4.2 billion kilograms) that are economically minable by 1980 standards. At least several billion pounds of copper probably exist in other parts of the same shale beds, but not enough data are available to measure the amount. A small amount, about 250 million pounds (113 million kilograms), of native copper is known to remain in one abandoned mine, and additional but unknown amounts remain in other abandoned mines. About 13.25 billion tons (12.02 billion metric tons) of banded iron-formation averaging roughly 30 percent iron are known within 500 feet (152.4 meters) of the surface in the Gogebic, Marquette, and Iron River-Crystal Falls districts. A small percentage of that might someday be minable as taconite, but none is now believed to be economic. Some higher grade iron concentrations exist in the same iron-formations. Such material was the basis of former mining of iron in the region, but a poor market for such ore and depletion of many deposits have led to the decline of iron mining in the quadrangle. Iron mines of the quadrangle were not being worked in 1980. Many parts of the quadrangle contain belts of favorable host rocks for mineral deposits. Although deposits are not known in these belts, undiscovered deposits of copper, zinc, lead, silver, uranium, phosphate, nickel, chromium, platinum, gold, and diamonds could exist.

Michigan, Wisconsin↗
USGS1982

Mineral-resource assessment of the Iron River 1° x 2° quadrangle, Michigan and Wisconsin

The Iron River 1° x 2° quadrangle contains identified resources of copper and iron. Copper-rich shale beds in t1n north part of the quadrangle contain 12.2 billion pounds (5.5 billion kg) of copper in well-studied deposits including 9.2 billion pounds (4.2 billion kg) that are economically mineable by 1980 standards. At least several billion pounds of copper probably exist in other parts of the same shale beds but not enough data are available to measure the amount. A small amount, about 250 million pounds (113 million kg), of native copper is known to remain in one abandoned mine, and additional but unknown amounts remain in other abandoned mines. About 13.25 billion tons (12.02 billion t) of handed iron-formation averaging roughly 30 percent iron are known within 500 feet (152.4 m) of the surface in the Gogebic, Marquette, and Iron River-Crystal Falls districts. Some, probably small, percentage of that might someday be mineable as taconite, but none is now believed to be economic. Some higher grade iron concentrations exist in tin same iron-formations. Such material was the basis of former mining of iron in the region, but a poor market for such ore and depletion of many deposits has lead to the decline of iron mining in the quadrangle. No iron mines of the quadrangle were being worked in 1981. Many parts of the quadrangle contain belts of favorable host rocks for mineral deposits. Although no deposits are known in these belts, undiscovered deposits of copper, zinc, lead, silver, uranium, phosphate, nickel, chromium, platinum, gold, and diamonds could exist.

Michigan, Wisconsin↗
USGS1981

Geology of central Lake Michigan

The geology beneath Lake Michigan between 43°00' and 44°00' N and between 86°30' and 87°40' W is interpreted from a synthesis of 1,700 km of continuous seismic reflection profile data, bathymetry, grab samples, and onshore surface and subsurface information. The continuous seismic reflection profiles and bathymetry provided information for maps of unconsolidated sediment thickness and Paleozoic bedrock topography. The map of unconsolidated sediment (primarily Pleistocene) shows thicknesses ranging from 180 m in a steep-walled, northeast-trending valley to less than 10 m over a mid-lake topographic high. This valley and the mid-lake high are the dominant topographic features developed on the gently eastward-dipping Paleozoic rocks along this part of the western flank of the Michigan basin. Two structural-stratigraphic cross sections of the study area were constructed by utilizing a composite subsurface-surface section for eastern Wisconsin and two control wells in western Michigan. The cross sections, grab samples previously described in the literature, the bedrock topographic map, and published maps were used to construct a Paleozoic geologic map for central Lake Michigan. Rocks from Middle Silurian through Early Mississippian age form subcrops beneath the study area, whereas rocks of Early Silurian, Ordovician, and Late Cambrian age are present at greater depth. The Upper Cambrian rocks unconformably overlie Precambrian igneous and metamorphic rocks. The structural-stratigraphic cross sections also allow us to speculate about the petroleum potential beneath Lake Michigan. The possibility of oil occurrences within the Silurian is enhanced by major east-west facies changes, and other horizons with promise are present in Devonian and Ordovician rocks. Although Michigan and Wisconsin laws currently prohibit petroleum exploration in Lake Michigan, it is an area with future potential.

Michigan, Wisconsin↗
USGS1981

Airborne electromagnetic and magnetic survey of parts of the Upper Peninsula of Michigan and Northern Wisconsin

The data presented in this report is from an airborne electromagnetic INPUT (Registered trademark of Barringer Research Ltd.) and total field magnetic survey conducted by Geoterrex Limited of Ottawa Canada. The survey is located in eight areas in the Upper Peninsula of Michigan and one area in Northern Wisconsin. The accompanying report describes the basic parameters for the areas surveyed (figure 1). All of the areas except area E (figure 1) are within the Iron River 2° quadrangle. This quadrangle is being studied as part of the U.S. Geological Survey (USGS) CUSMAP (Conterminous United States Mineral Appraisal Program) project. The survey was done in order to provide geophysical information which will aid in the integrated geological assessment of the Iron River 2° quadrangle.

Michigan, Wisconsin↗
USGS1977

Geology and Rb-Sr age of Precambrian W Puritan Quartz Monzonite, northern Michigan

The Puritan Quartz Monzonite, in the western part of the Upper Peninsula of Michigan, composes a batholith at least 50 kilometres long and as much as 20 km wide on the south side of the Gogebic iron range. It is associated with subaqueous metavolcanic rocks assigned to the Precambrian W Ramsey Formation and with a complex gneissic unit of the same age. The quartz monzonite has a Rb-Sr isochron age of 2,710±140 million years and an initial 87 Sr/ 86 Sr of 0.7015±0.0017. The scatter of data points in excess of analytical error is interpreted as indicating that minor cataclasis and retrograde metamorphism produced slight open-system behavior in Precambrian X (circa 1,800 m.y.) time. The Puritan Quartz Monzonite and associated volcanic rocks are equated with similar Precambrian W greenstone-granite complexes in northern Minnesota, and clearly are a part of the Precambrian W greenstone terrane, as defined previously for the Lake Superior region.

Michigan, Wisconsin↗
USGS1975

Lower Keweenawan volcanic rocks of Michigan and Wisconsin

Unconformable sequences of Keweenawan volcanic rocks occur in Michigan and adjacent Wisconsin. The sequences differ in types of rocks, magnetic properties, metamorphic grade, and pattern of structural deformation; they had different vent areas and were deposited in basins that were only partly overlapping. The older sequence includes the Bessemer Quartzite and two newly named formations that are here assigned to the lower Keweenawan. The younger sequence includes the well-known Portage Lake Volcanics and a younger unnamed formation, both of middle Keweenawan age. Formerly the older rocks were interpreted as a fault-repeated part of the Portage Lake Volcanics, but new evidence indicates that these older rocks had been metamorphosed and tilted and were being eroded in middle Keeweenawan time.

Michigan, Wisconsin↗
USGS1974

Hydrology and trout populations of cold-water rivers of Michigan and Wisconsin

Statistical multiple-regression analyses showed significant relationships between trout populations and hydrologic parameters. Parameters showing the higher levels of significance were temperature, hardness of water, percentage of gravel bottom, percentage of bottom vegetation, variability of streamflow, and discharge per unit drainage area. Trout populations increase with lower levels of annual maximum water temperatures, with increase in water hardness, and with increase in percentage of gravel and bottom vegetation. Trout populations also increase with decrease in variability of streamflow, and with increase in discharge per unit drainage area. Most hydrologic parameters were significant when evaluated collectively, but no parameter, by itself, showed a high degree of correlation with trout populations in regression analyses that included all the streams sampled. Regression analyses of stream segments that were restricted to certain limits of hardness, temperature, or percentage of gravel bottom showed improvements in correlation. Analyses of trout populations, in pounds per acre and pounds per mile and hydrologic parameters resulted in regression equations from which trout populations could be estimated with standard errors of 89 and 84 per cent, respectively.

Michigan, Wisconsin↗