Description of the Montevallo And

DESCRIPTION OF THE MONTEVALLO AND By Charles Butts INTRODUCTION south of New England is divisible into four parts called Birmingham district is considerably lower than that of the LOCATION AND EXTENT provinces. These are, from southeast to northwest, the Pied adjacent provinces. mont province, the Blue Ridge province, the Valley and The rocks of this province are not crystalline, like those of As shown by the key map (fig. 1) the Montevallo and Ridge province, and the Appalachian Plateaus. West of the the Piedmont and Blue Ridge provinces, but are all sedimen Columbiana quadrangles are in the north-central part of Ala Appalachian Plateaus are the Interior Low Plateaus, which are tary. They include limestone, dolomite, conglomerate, sand bama, mainly in Shelby, Bibb, and Chilton Counties. The included in the Interior Plains by the Association of American stone, and shale, which have been greatly disturbed by folding northwest corner of the Montevallo quadrangle includes a Geographers but which in the opinion of some, including and faulting. small area of Jefferson County, and the eastern part of the the writer, should be regarded as part of the Appalachian Highlands. C AH ABA RID GB S The dividing line between the Piedmont province and the The Valley and Ridge province in Alabama is divided Blue Ridge province is the eastern foot of the Blue Ridge and into the Cahaba Ridges, Birmingham Valley, and Coosa Val the foot of the high but irregular eastern scarp of the moun ley. Although in general a valley, this province contains tains that form the southern extension of the Blue Ridge in many high ridges extending parallel to its general direction, of western North Carolina and northern Georgia. The boundary which Red Mountain is a good example. Most of these ridges between the Blue Ridge province and the Valley and Ridge lie along the west side of the valley from Pennsylvania to province is the western base of the Blue Ridge of Virginia and Alabama. In Alabama the ridge section includes all the val of the high mountains of eastern Tennessee. This boundary ley west of the east boundary of the Coosa coal field and west continues into northwestern Georgia, to its intersection with of a line in continuation of that boundary southwest to Calera, the boundary between the Piedmont and Blue Ridge provinces, thence northwest to Maylene by way of Montevallo, thence about 15 miles southeast of Dalton. The Blue Ridge province southwest through the middle of the southern part of the thus terminates in northwestern Georgia. Thence the indefi Cahaba coal field. The north end of the ridge area curves nite boundary between the Piedmont and Valley and Ridge eastward and narrows to a point a few miles southeast of provinces runs southwestward through Sylacauga to the Gadsden. It includes Blount and Chandler Mountains. The Coastal Plain in Chilton County, Ala. The boundary between name Cahaba Ridges is here applied to this part of the Valley the Valley and Ridge province and the Appalachian Plateaus and Ridge province in Alabama. is, in Pennsylvania, the escarpment known as the Allegheny Front or Allegheny Mountains; in southwestern Virginia and BIRMINGHAM VALLEY through Tennessee, the Cumberland escarpment or Cumber The belt of relatively low land lying between Shades Moun 87' land Mountain; and in Alabama, the eastern scarp of Lookout tain on the southeast and Sand Mountain on the northwest FIGURE 1. Index map of northeastern Alabama and portions of adjacent Mountain and the eastern boundary of the Warrior coal field. and extending the full length of the Cahaba coal field is com States The western boundary of the Appalachian Plateaus through monly called Birmingham Valley. It includes Shades, Jones, The location of the Montevallo and Columbiana quadrangles, covered by Folio 226, is shown by the darker ruling. Published folios describing other quadrangles, indicated by lighter ruling, Tennessee, lying midway between Knoxville and Nashville, is and Opossum Valleys, Red Mountain, and Enon or Flint Ridge. are the following: Nos. 2, Ringgold; 6, Chattanooga; 8, Sewanee; 19, Stevenson; 20, Cleve a broken escarpment 800 to 1,000 feet high, separating the land; 85, Gadsden ; 78, Rome; 175, Birmingham; 221, Bessemer-Vandiver Cumberland Plateau from the Highland Rim. This boundary COOSA VALLEY Columbiana quadrangle includes small areas of Coosa and is extended northeastward through eastern Kentucky and East of the Cahaba Ridges is the Coosa Valley, which is Talladega Counties. The quadrangles are bounded by paral central Ohio to the vicinity of Cleveland, although it is not the broad, generally flat, low country occupied by Coosa River lels 33° and 33°15' and meridians 86°30' and 87°." Each sharply defined in those States. and its tributaries and farther southwest by Cahaba River and quadrangle covers one-sixteenth of a "square degree" and has its eastern tributaries. The lower part of the Coosa Valley lies PIEDMONT PBOVINCE an area of 250 square miles. in the Piedmont province. The Piedmont province is a rolling upland 1,100 feet above GENERAL RELATIONS sea level at the foot of the Blue Ridge and 500 feet or less APPALACHIAN PLATEAUS Northern Alabama is in the southern part of the Appalach along the "fall line." Its generally flat surface has been The subdivision of the Appalachian Highlands known as the ian Highlands. 2 This physiographic division of the United deeply trenched by the streams that flow across it. It is Appalachian Plateaus is practically coextensive with the Appa States extends from the Atlantic Plain on the east to the underlain by very ancient and crumpled crystalline rocks, lachian coal fields. It is relatively high, ranging from 500 feet both igneous and metamorphic. A small area in the southeast above sea level in the Warrior coal field to more than 4,500 corner of the Columbiana quadrangle lies in the Piedmont feet in Pocahontas County, W. Va., and about 2,000 feet in province. western New York. In Tennessee it slopes somewhat west BLUE EIDGE PROVINCE ward, from about 2,000 feet above sea level on the east to about 1,800 feet on the west, where it terminates in the steep The Blue Ridge province is narrow at its north end in scarp 800 to 1,000 feet high, descending to the Highland Rim Pennsylvania but more than 60 miles wide in North Carolina. of middle Tennessee. As a whole this province may be It is a rugged region of hills and ridges and deep, narrow val regarded as a series of plateaus extending from New York to leys. The altitude of the higher summits in Virginia is 3,000 Alabama, which have been more or less separated into parts or, to 5,719 feet above sea level, and in western North Carolina in large areas, nearly obliterated by erosion. Because they Mount Mitchell, 6,711 feet high, is the highest point east of have been so much eroded they are called dissected plateaus. Mississippi River. Throughout its extent this province stands The separated parts have received names, and one of them, the up conspicuously above the adjoining provinces, from each of Cumberland Plateau in Tennessee, is the part of the province which it is separated by a steep, broken, rugged front from that most nearly embodies the conception of a plateau. 1,000 to 3,000 feet high. The rocks of this province corn- The rocks of the Appalachian Plateaus are mostly sandstone, rise closely folded quartzite, slate, schist, gneiss, granite, and conglomerate, shale, and coal. In contrast with those of the greenstone. Valley and Ridge province the strata of the plateaus have VALLEY AND KIDGE PKOVINCE been but slightly disturbed. GENERAL FEATURES TOPOGRAPHY OF THE QUADRANGLES FIGURE 2. Map of the southern part of the Appalachian province, showing its physiographic divisions and its relation to the Coastal Plain The Valley and Ridge province, in which the Montevallo GENERAL FEATURES and Columbiana quadrangles are mainly situated, is a belt Interior Plains on the west and from Canada and Lake Erie 50 to 80 miles wide, extending from Canada into Alabama, The south half of the Montevallo quadrangle and nearly all on the northeast into Alabama and Georgia on the southwest. which is on the whole lower than the Blue Ridge province on of the Columbiana quadrangle lie in the Coosa Valley; the The boundaries of the Appalachian Highlands and of the the east and the Appalachian Plateaus on the west. Near Big rest of the area lies in the Cahaba Ridges. A line drawn from larger subdivisions are shown on the sketch map (fig. 2). Stone Gap, Va., the crest of the Big Black Mountains is 3,000 Calera to Montevallo, passing 1 mile south of Hardys, thence APPALACHIAN HIGHLANDS feet above the valley on its northwest side, and in northern north to Lacy, thence due southwest to Garnsey would approx Tennessee Holston Mountain, near the northwest front of the SUBDIVISIONS imately mark the boundary between the two subdivisions. Blue Ridge province, rises nearly 3,000 feet above the valley The region is one of late mature topography. The streams On the grounds of differences in topography, rocks, and on its southeast side. are approximately graded and reach all parts of the area, so geologic structure the portion of the Appalachian Highlands In other places, as in the Birmingham district, the valley is that no extensive undrained surface remains. The upland not so distinctly defined by high escarpments. Nevertheless surfaces probably nearly coincide with an ancient peneplain 1 Surveyed in cooperation with the Geological Survey of Alabama. Text submitted in August 1924. the altitude of the limestone and shale valleys that constitute below which the larger streams have intrenched their valleys 2 Assoc.

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