Description of the Waynesburg Quadrangle

DESCRIPTION OF THE WAYNESBURG QUADRANGLE By Ralph W. Stone. INTRODUCTION. In the northern part of the province the arrange The surface features of this plateau are variable, nounced anticlines, two of these disappearing near ment of the drainage was largely determined by but there is not so much diversity as in the higher the West Virginia line. Farther south the num LOCATION AND AKEA. conditions during the Glacial epoch. Before that plateau. In Kentucky and Tennessee it is pre ber is less, until on Kanawha River the regular The Waynesburg quadrangle is located in the time it is supposed that all of the streams north served in large areas as a nearly featureless plain, westward dip is interrupted by only one or two southwestern pa.rt of Pennsylvania, as will be seen of .central Kentucky flowed to the northwest, and but in other States it was less perfectly developed, folds of small proportions. by reference to the key map on the cover of the folio. discharged their waters through the St. Lawrence and has suffered greatly from dissection since it It extends from latitude 39° 45' on the south to 40° system. The encroachment of the great ice sheet was elevated. STRATIGRAPHY. on the north, and from longitude 80° on the east to closed this northern outlet, and new drainage lines West of the Highland Plateau there is a third The rocks which are exposed at the surface in 80° 15' on the west. It includes, therefore, one- were established along the present courses of the plain which is developed in the Central Basin of the Allegheny Plateaus belong entirely to the sixteenth of a square degree of the earth's surface, streams. Tennessee and in the western parts of Kentucky Carboniferous system. They include the Pocono, and has an area of 229.2 square miles. Surface relief. As the name Allegheny Plateaus and Indiana. Mauch Chunk, Pottsville, Allegheny, Conemaugh, The quadrangle is largely in Greene County, but implies, the surface of this division of the province and Monongahela formations and the Dunkard it extends into the southern part of Washington is composed of a number of plateaus. The highest GEOLOGY OF THE PLATEAUS. group. These will be described in the order of County, and includes a small portion of Fayette and most extensive plateau lies along the southeast Geologic structure. The structure of the Alle their age, beginning with the lowest. County on the east side of Monongahela River. ern margin of the division, and extends throughout gheny Plateaus is simple. The strata lie nearly Pocono formation. In this province the Pocono It extends to within 2 miles of the north line of its length. It is very old, and consequently is so flat, and their regularity is broken only by small formation forms the basal division of the Carbonif West Virginia and 15 miles of the east line of greatly dissected that its plateau character is not faults and low, broad folds. The most pronounced erous system. Its name is derived from the Pocono Ohio. It is named from the largest town within always apparent. Its surface rises from beneath fold is a low, broad arch known as the Cincinnati Mountains, in the eastern part of Pennsylvania, its borders, the county seat of Greene County. the Cretaceous cover in central Alabama at a height anticline. The main axis of this fold enters the where the formation consists largely of sandstone of 500 feet above sea level. From this altitude it Allegheny Plateaus from the direction of Chicago, and is over 1000 feet thick. It rests upon the red BELATION TO APPALACHIAN PROVINCE. ascends to 1700 feet at Chattanooga, 2400 feet at but a minor fold* from the western end of Lake rocks of the Catskill formation, the uppermost In its physiographic and geologic relations this Cumberland Gap, 3500 feet at New River, and Erie joins the major axis near Cincinnati. From member of the Devonian system. Although the quadrangle forms a part of the Appalachian prov probably reaches 4000 feet at its culminating point this point the axis of the anticline passes due south lower limit of the Pocono can not be determined ince, which extends from the Atlantic Coastal Plain in central West Virginia. From this point it to Lexington, Ky., and there curves to the south definitely from well records, it is believed that in on the east to the Mississippi lowlands on the west, descends to about 2800 feet on the southern line west parallel with the Appalachian Valley as far the Waynesburg quadrangle the formatioii is only and from central Alabama to Canada. of Pennsylvania and 2300 to 2400 feet in the cen as Nashville, Tenn. This anticline reaches its about 300 feet thick. Over a large area in Penn Appalachian province. With respect to topog tral part of the State. The plateau is widely devel maximum development in the vicinity of Lex sylvania the top is well marked by a calcareous raphy and the attitude of the rocks, the Appa oped in the northern counties of Pennsylvania and ington, where the Trenton limestone is exposed and sandy stratum, known as the Loyalhanna lachian province may be divided into two nearly throughout southern New York, and ranges in alti at an altitude of 1000 feet above sea level. In (Siliceous) limestone. (Charles Butts, Kittanning equal parts by an eastward-facing escarpment called tude from 2000 to 2400 feet. Tennessee it swells out into a dome-like struc- folio, No. 115, p. 5.) Where this stratum is the Allegheny Front. From Pennsylvania to'Ala This surface is best preserved in Alabama and i ture, which is exposed in' the topographic basin absent the top of the formation is not well defined. bama this separates the Allegheny Plateaus on the Tennessee, where it constitutes the Cumberland of central Tennessee. On the eastern margin of the coal field sandstone west from the Greater Appalachian Valley on the Plateau. North of Tennessee it doubtless was once The Cincinnati anticline divides the Allegheny predominates. , The Pocono contains, however, east. It is not a well-developed feature along the well developed, but now is difficult to identify. In Plateaus into two structural basins, which are best beds of ( gray sandy shale and occasional beds of whole line, but is especially prominent in parts of northern West Virginia and northern Pennsylvania known from the coal fields which they contain. red shale wnich, though usually thin, may be of Pennsylvania and Tennessee (see fig. 1). there are a few remnants of high, level land which The western basin extends far beyond the limits of considerable thickness. In southwestern Pennsyl appear to be parts of the original surface of this the province, and contains the Eastern Interior coal vania the formation is generally under cover, but plateau, but it is generally so dissected that only field of Illinois, Indiana, and Kentucky. The is penetrated in drilling deep wells for oil and the hilltops mark its former position. In Penn eastern basin lies entirely within the limits of the gas. In the southeastern part of the Appalachian sylvania the remnants of this plateau, which is ten Allegheny Plateaus, and includes the Appalachian field, in Virginia and West Virginia, the forma tatively correlated with the Cumberland Plateau, coal field. The Waynesburg quadrangle is situ tion contains workable beds of coal of limited are known as the Schooley peneplain. ated entirely within the Appalachian coal field, extent, and in parts of Pennsylvania it includes Throughout most of the province there are knobs and hence a somewhat detailed description of this thin worthless beds. and ridges which rise to a greater height than the field is necessary in order to present a clear idea Mauch Chunk formation. This formation over surface of the plateau, but generally they may be of the geologic features of the quadrangle. lies the Loyalhanna (Siliceous) limestone in' the distinguished by the fact that they stand above the Structure of Appalachian coal field. The geo Allegheny Front, along Conemaugh River east of general level of the surrounding hills. logic structure- of the Appalachian coal field is very Blairsville, and along Chestnut Ridge in Fayette The surface of the high Cumberland Plateau simple, consisting, in a general way, of a broad, County. It takes its name from Mauch Chunk, slopes to the west, but it is usually separated from flat, canoe-shaped trough. This is particularly in the anthracite coal region, where it is over / v>- the next lower or Highland Plateau by a generally true of the northern extremity. The deepest 2000 feet thick in the deep synclines and where FIG. 1. Diagram of northern portion of the Appalachian westward-facing escarpment. This escarpment is part of this trough lies along a line extending it is described as being composed largely of red province, showing physiographic divisions. most pronounced in Tennessee, where it has a southwest from Pittsburg across West Virginia to shale (Second Geol. Survey Pennsylvania, Final The general topographic features of the northern height of 1000 feet. Toward the north the height Huntington, on Ohio River. Toward this line Rept., vol. 3, pt. 1, p. 182). In the Allegheny part of the province are well illustrated by fig. 6 of the escarpment diminishes to 500 feet. In cen the rocks dip from both sides of the trough. Front it is made up of about 150 feet of heavy (illustration sheet). East of the Allegheny Front tral Kentucky and north of Ohio River it is so About the canoe-shaped northern end the rocks grayish to greenish sandstone at the bottom, and the topography consists of alternating ridges and indistinctly developed that it has not been recog outcrop in a rudely semicircular line and at all 100 feet of soft red shale.

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