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Thomas C. Winter

Publications and source records attributed to Thomas C. Winter.

43 records · Page 3Linked to original sources
USGS1973

Petrography and stratigraphy of glacial drift, Mesabi-Vermilion Iron Range area, northeastern Minnesota

Glacial deposits in the Mesabi-Vermilion Iron Range area consist of four major till units and associated glaciofluvial sediments. Particle-size data and pebble, heavy-mineral, clay-mineral, and percentage-soluble content were used in addition to field description of color and texture to describe and correlate the drift units. The lowermost till unit, basal till, occurs in only a small number of mines, but the mines are scattered across the entire Iron Range. The till is dark gray to dark greenish gray and brownish gray, sandy, silty, and calcareous. Pebbles are largely granitic and metamorphic rocks of local origin, but include limestone, dolomite, shale, basalt, felsite, agate, and gabbro. Clay-mineral content is largely illite. The age of the till is probably middle or early Wisconsin but could be pre-Wisconsin. The middle till unit, bouldery till, is the thickest and most widespread of the four tills. It is gray, yellow, red, orange, or brown, sandy, silty, noncalcareous and contains abundant cobbles and boulders. Pebbles are largely granitic and metamorphic rocks of local origin, but also include gabbro, basalt, and felsite in minor amounts. Montmorillonite is the most common clay mineral. Colored bouldery till below gray bouldery till may be a separate subunit distinguished largely on particle-size differences, but the overall characteristics are similar to the other bouldery till. The till was deposited by the Rainy lobe, which has a minimum age of 14,000 to 16,000 years before present. The uppermost, or surficial, tills were deposited contemporaneously by two minor sublobes of the Des Moines lobe about 12,000 years ago. Brown silty till occurs in the western and north-central part of the study area. It is light to medium brown, sandy, silty, and calcareous. Pebbles are largely granitic and metamorphic rocks of local origin, but include limestone, dolomite, shale, basalt, felsite, and gabbro. Clay-mineral content is largely mixed-layered montmorillonite and illite. Red clayey till occurs in the south-central part of the area. It is red to reddish brown, clayey, silty, and calcareous. Pebbles are similar to those in the brown silty till, but contain less limestone than the brown till. Glaciofluvial sediments are common between the various till units throughout the area, but are thickest near the east and near the west ends of the Iron Range.

Minnesota↗
USGS1969

Water resources of the Buffalo River Watershed, West-central Minnesota

The Buffalo River watershed includes two general physiographic areas – a glacial lake plain and an glacial moraine. The lake plain, which was formed by Glacial lake Agassiz more than 9,000 years ago, is extremely flat – sloping only a few feet per mile westward near the Red River of the North. The moraine is largely an area of gently rolling hills, but in the eastern “tail” of the watershed the relief locally is over two hundred feet. The watershed has an area of about 1,690 square miles and includes most of Clay County and parts of Wilkin, Otter Tail, Becker, and Norman Counties. The population of the area is about 45,500 – 31,000 urban and 14,500 rural. The economy is largely agricultural. Sugar beet and wheat farming are dominant in the areas of clay and silt; potato farming is confined mainly to the sandy areas. Dairying and stock raising is important in the morainal area. The larger industries are located in Moorhead and consist of sugar beet, potato, and dairy product processing. Water-based recreation consists mostly of fishing in the larger lakes in the morainal area, and water-fowl hunting in the area of prairie potholes – the western part of the morainal area.

Minnesota↗
USGS1968

Water resources of the Mustinka and Bois de Sioux Rivers watershed, west-central Minnesota

The Mustinka and Bois de Sioux Rivers watershed is mantled by till deposits with scattered sand deposits. The west-central and northwestern part of the watershed was covered by Glacial Lake Agassiz and the resulting land surface is a flat, lake-washed till plain. Patches and ridges of sand scattered throughout the lake plain were formed as beach ridges and offshore bars. Small, isolated areas of lake clay also occur within this area. The remainder of the watershed is glacial moraine characterized by rolling topography in all but the extreme eastern edge which has more local relief and more permanent lakes. Alluvial sand deposits are found in the eastern part of the morainal area. The drainage area of the watershed in Minnesota is 1,429 square miles. The area includes mors of Traverse County and parts of Big Stone, Stevens, Grant, Ottertail, and Wilkin Counties. Population within the watershed unit is about 20,000. The largest community, Wheaton, has a population of 2,102. The agricultural economy of the area is concentrated on grain farming, although some dairying is carried on. The principal grain crops are corn and oats. Flax, soybeans, and barley are also very commonly grown. The natural vegetation in the area was largely prairie. A hardwood deciduous forest grew only on the extreme eastern edge. Today, the area is almost entirely farm land containing numerous local woodlots. Outdoor recreation is concentrated on waterfowl and pheasant hunting. Fishing is done in Lake Traverse and in the larger lakes in the eastern part of the morainal area.

Minnesota↗
USGS1967

Water resources of the Two Rivers Watershed, Northwestern Minnesota

The Two Rivers watershed includes two physiographic areas a lake plain and a till plain – within its 1,232 square miles. It lies in parts of Kittson and Roseau counties and includes the drainage basins of the Two Rivers and Joe River. The flat lake plain which extends 15 to 20 miles east of the Red River of the North is extensively cultivated for small grains and sugar beets. The gently undulating till plain is cultivated largely for small grains and hay. The areas not under cultivation support a forest of poplar with some maple and oak. Oak is the predominate tree on the sandy ridges. The large peat areas are covered with brush and marsh grasslands. Outdoor recreational facilities in the watershed consist principally of the Lake Bronson Park, water-fowl hunting in the extensive marshlands, and deer and small game hunting in the forested areas.

Minnesota↗
USGS1967

Water resources of the Roseau River Watershed, Northwestern Minnesota

The drainage area of the Roseau River consists of 2,060 square miles above its confluence with the Red River of the North. About 1,150 square miles lie in the United States and 910 square miles in Canada. This report deals only with that portion within the United States, except for a detailed analysis of low flow characteristics of tributary streams. Most of the area is within Roseau County, but small portions are in Marshall, Beltrami, Lake of the Woods, and Kittson Counties. Most of the watershed has little relief, and lies entirely within the plain of former Glacial Lake Agassiz. However, the flat topography of this lake washed till plain is broken by beach ridges in its southwestern part and Beltrami Island, a topographic high underlain by sand, in tis southeastern part. Population within the watershed is about 8000. The town of Roseau, the largest community, has a population of 2146 (1960). The watershed has an agricultural economy. Spring wheat, oats, and bluegrass seed are the three most important crops in the area, but many other small grains, legumes, and grasses are also grown. Dairy farming and sheep raising are the most important types of livestock production and for many farms stock is the major sources of income. Large areas of the watershed are peat lands, covered with shrubs, marsh grasslands, and spruce, tamarack, and cedar trees. Forest vegetation in the remainder of the area is largely aspen, but oak is common on the beach ridges and jack pine is common on Beltrami Island. Outdoor recreation in the area is primarily hunting of deer, small game, and waterfowl. This report is a general appraisal of the water resources in the Roseau River watershed unit. Detailed studies of water movement through the ground-water reservoir are needed for more exact determination of the amount of water immediately available and the specific effects of water-management practices.

Minnesota↗
USGS1963

Two pollen diagrams from southeastern Minnesota: Problems in the regional late-glacial and postglacial vegetational history

Kirchner Marsh and Lake Carlson are located 3 miles apart in Dakota County about 15 miles south of Minneapolis in the St. Croix moraine, which was formed by the Superior lobe during the Gary phase of the Wisconsin glaciation. During the Mankato phase that followed, the Des Moines lobe advanced to within a few miles of the sites. The region today is in a mixed-oak forest, with a maplebasswood forest 15 miles to the west and a re-entrant of the prairie on the sand plain south of the moraine. The general limit of coniferous trees is about 50 miles northeast of the sites, although outliers, especially of Pinus strobus, may be found along the Mississippi Valley a few miles to the east. One sediment core 12-13 m long from each site was analyzed for pollen content at 5-25-cm intervals. Diagrams based on percentage of total pollen (trees, shrubs, wind-pollinated herbs) show essentially identical sequences at the two sites, starting with the late-glacial phase of ice retreat. The diagrams have been subdivided into pollen zones according to the A-B-C sequence introduced by Deevey for New England. The late-glacial pollen record starts at Kirchner Marsh with a short Picea-Cyperaceae-Gramineae phase (Zone K), believed to represent a spruce parkland. Its C-14 date of 13,270 BP and the stratigraphy indicate a pre- Two Creeks and post- Gary correlation. Apparently the Kirchner site did not become established as a lake until this time owing to persistence of dead ice in the moraine. The absence of pollen of specific tundra indicators and the presence of pollen of such thermophilous plants as Fraxinus, Quercus, Corylus, Ambrosia, Humulus, and Typha latifolia imply that the climate was cool rather than cold. Zone A-a, which follows, correlates with the Two Creeks interstade. It is marked by the dominance of Picea, with appreciable percentages of Fraxinus and Ambrosia and with minor amounts of other thermophilous plants and the normal boreal associates of spruce like Betula, Larix, and Salix. Zone A-b, starting 12,050 C-14 years ago, correlates with the Valders ice advance. It is represented at both Kirchner and Carlson and shows the withdrawal of Fraxinus and Ambrosia and the slight rise of Artemisia. Except for the absence of pine in the late-glacial assemblage the vegetation implied by these three zones seems to have its closest modern counterpart in the southern fringe of the Boreal Forest of the Riding Mountain region of southwest Manitoba. It is concluded that pine did not migrate southward with the spruce during the Wisconsin glaciation, at least in the western Great Lakes region, and was thus eliminated from this region. During the lateglacial phases of ice retreat, herbs and spruce pioneered on the deglaciated terrain; pine did not follow until the destruction of the spruce forest at the end of the late-glacial phase. Zone B introduces postglacial time. It represents the time of rapid Vegetational succession following the deterioration of the spruce forest. Simultaneous maxima of Betula, Alnus, Fraxinus, and Abies occurred 10,230 years ago at Kirchner Marsh. These were followed rapidly by a Pinus maximum and then a rise of Ulmus, Quercus, and other deciduous types, dated as 9300 years ago at the correlative site of Madeha. This succession may represent differential rates of migration from refuges south and east of Minnesota . Deciduous trees dominate the C Zones. Zone C-a shows Ulmus and Ostrya /Carpinus followed by Quercus; it probably represents principally a mesic maple-basswood forest changing to oak. Zone C-b represents the advance of prairie into the region at the expense of the oak woodland or savanna. The large and abrupt fluctuations in the curves for Ambrosia-type and Chenopodiineae, especially at the Carlson site, may record encroachment of annual weeds onto intermittently dried lake bottoms. C-14 dates place Zone C-b between 7100 and 5100 years ago. In Zone C-c the Quercus again dominates until the abrupt increase in Ambrosiatype and Chenopodiineae that marks the time of forest clearance and land settlement 50-75 years ago.

Minnesota↗