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GEOLOGY AND MINERAL RESOURCES OF THE

CLEVELAND DISTRICT, OHIO

By H. P. CUSHING, FRANK LEVERETT, and FRANK R. Van HORN'

INTRODUCTION

By H. P. Cushing and FRANK LEVERETT

GENERAL RELATIONS

The Cleveland district, as described in this bulletin, lies in northeastern Ohio between the south shore of Lake Erie and parallel 41° 15' and between meridians 81° 30' and 82°. It comprises the Berea, Cleveland, and Euclid quadrangles, which have an aggregate land area of about 503 square miles. Nearly the whole of Cuyahoga County and small parts of Lorain, Medina, and Summit Counties are included in it. The city of Cleveland lies along the shore of Lake Erie in the northern part of the district. Adjoining it are several large suburbs, such as lie near to most flourishing cities. Berea and Bedford are villages 10 and 11 miles, respectively, from the city hall of Cleveland.

In its general geographic and geologic relations the area forms a ! part of the rather indefinite border zone in which the Appalachian

Plateaus merge into the glaciated part of the Central Lowland, and it thus partakes somewhat of the character of both provinces, which are distinguished only by broad, general differences.

GENERAL GEOGRAPHY AND GEOLOGY OF THE REGION

PHYSIOGRAPHIC DIVISIONS

Portions of two major physiographic divisions are included within the State of Ohio—the Appalachian Plateaus on the southeast and the Central Lowland on the northwest-each occupying about half the State. (See fig. 1.)

The Appalachian Plateaus include the large areas of hill land of southern New York, northwestern Pennsylvania, eastern Ohio, West Virginia, and eastern Kentucky. In northeastern Ohio the hilltops in this division range from 1,100 to 1,400 feet above sea level. The plateau is terminated on the north by the Portage escarpment, which

1 Since the death of Professor Cushing, Prof. C. R. Stauffer has rendered valuable aid in mapping and Prof. J. E. Hyde has aided in the revision of the manuscript. Acknowledgment is also made for access to an unpublished manuscript on the Quaternary geology of the Cleveland district by Prof. Frank Carney. The description of the Quaternary here presented by Mr. Leverett is based on his own earlier and later studies.

1

is prominent and continuous from Cleveland eastward to Albany, N. Y. In the vicinity of Cleveland the escarpment that bounds the Appalachian Plateaus turns more to the south and passes between Columbus and Newark, through Chillicothe, and on southward into Kentucky. In the northern part of Ohio this escarpment is as high as the Portage escarpment, on the east, but its slope is more gentle and it is not so impressive. South of Newark it is bold and precipi tous and is fully 300 feet high.

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FIGURE 1.-Outline map of Ohio, showing physiographic provinces. The Cleveland district is

shown by the shaded area. The numbers at the sides of the area indicate the three quadrangles: 1, Cleveland; 2, Euclid; 3, Berea

Northwest of the Appalachian Plateaus is the Central Lowland, which includes the lowland that surrounds the southern part of the Great Lakes and extends west as far as the border of the Great Plains. This region consists of rolling plains rather than hills, but its altitude in many places is equal to that of the Ohio part of the Appalachian Plateaus. In places the lowland is very hilly.

In the region of the lower Great Lakes the Central Lowland consists of a number of separate and distinct plains, which are known by the names Erie Plain, Huron Plain, and Ontario Plain. The lowest of these plains is the Ontario; this is separated from the Huron by a distinct rise or escarpment, and the Huron is separated by a similar feature from the higher Erie Plain. The sequence of terraces and escarpments can be carried farther, as the Erie Plain is separated from the generally flat top of the Appalachian Plateaus by the Portage escarpment.

The Erie Plain lies at the base of the Portage escarpment across western New York and extends along the prolongation of the escarpment across northwestern Pennsylvania and northeastern Ohio. It forms a large portion of the Ontario Peninsula between Lakes Huron and Ontario, and Lake Erie occupies a shallow depression in its surface. In New York the plain becomes very narrow east of Buffalo, and it pinches out against the Portage escarpment just east of Auburn.

From Buffalo to Cleveland the width of the plain between the shore of the lake and the escarpment is only a few miles, but west of Cleveland the escarpment swings away from the lake toward the southwest, and the plain broadens rapidly and increases in altitude. Within Ohio it ranges in altitude from 573 feet at the lake shore to nearly 1,000 feet. Its relief is slight, and it is on the whole a gently rolling, northward-sloping plain, interrupted only by morainic ridges and by the beaches and low cliffs of the glacial lakes.

Across western New York the Erie Plain is sharply separated from the Huron Plain by the low Onondaga escarpment. West of Buffalo, however, this escarpment becomes barely discernible, so that in Ontario the Huron and Erie Plains are practically merged into one. In Ontario in general the southwestern half of the triangular peninsula between Lakes Ontario and Huron belongs to the Erie Plain and the northeastern half to the Huron Plain. Westward across this peninsula the Huron Plain gradually rises and becomes higher than the Erie Plain, parts of it south of Georgian Bay being more than 1,500 feet above sea level.

The Niagara escarpment separates the Huron Plain from the Ontario Plain. East of Rochester these two plains merge into one by the disappearance of the escarpment, but at Rochester it is about 100 feet high, at Niagara about 200 feet, and it crosses the Ontarian Peninsula with steadily increasing altitude. It turns northwestward at Hamilton and continues to Georgian Bay, where, in the Blue Mountains, it has an altitude of more than 800 feet. Thence it crosses to northern Michigan, turns southward through eastern Wisconsin, and dies out in northern Illinois.

The Ontario Plain lies between the Niagara escarpment and the Laurentian Plateau. In New York its altitude ranges between 250 and 500 feet above sea level. Across Ontario the altitude increases and attains more than 700 feet south of Georgian Bay.

The Cleveland area includes the margins of the Appalachian Plateaus and the Central Lowland and the border zone between them. The larger topographic features are due to the bedrock surface and incised stream valleys, largely masked but not obliterated by the covering of drift left by the glaciers, and the minor features are due to glaciation and the action of glacial lakes. The northwestern twothirds of Ohio, including the Cleveland area, was covered by the great ice sheets of the Pleistocene epoch; the southern boundary of the glaciated area crosses Ohio from the middle of the east side to the southwest corner of the State, running obliquely across plateau and lowland,

DRAINAGE

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The greater part of northern Ohio is drained to the St. Lawrence River and the remainder to the Ohio River. The Erie Plain is drained directly into Lake Erie, except that part lying east of Buffalo, which drains into Lake Ontario. The Ontario Plain is drained chiefly into Lake Ontario, but the western part drains into Lake Huron and the extreme eastern part into the Mohawk River.

The northern and northeastern margins of the Appalachian Plateaus drain into Lakes Erie and Ontario, chiefly through short streams that head not far back from the crest of the escarpment, through which they flow in deep, narrow valleys. The Grand River, in northeastern Ohio, is an exception, in that its valley across the escarpment is very broad. The Genesee River, in western New York, is a notable exception of another sort, as it rises in northern Pennsylvania far back from the escarpment and trenches it in a picturesque gorge. In northern Ohio the Grand, Chagrin, Cuyahoga, Rocky, Black, and Vermilion Rivers all rise not far within the plateau and flow north to Lake Erie. The greater part of the plateau in Ohio is drained southward into the Ohio River by means of streams that, in southeastern Ohio, occupy deep, narrow valleys; among these the Muskingum is chief. The Scioto and Miami, of central and southwestern Ohio, occupy much broader, shallower valleys. The divide between the drainage to Lake Erie and that to the Ohio runs rather close to the lake. It is inconspicuous and consists for the most part of low morainic ridges.

The preglacial drainage of the Appalachian Plateaus ran to the Erie Plain from all of eastern Ohio, northern West Virginia, and western Pennsylvania, a large part reaching it through the Grand River Basin. The drainage area of the Cuyahoga also extended farther south than at present. The change to present conditions came largely as a result of the glacial occupation. For a long time the glaciers wholly blocked the lower courses of many northwardflowing streams and forced them to seek outlets to the south. As the ice margin melted back from south to north the streams flowing southward filled up some of the northward-sloping drainage courses

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