DESCRIPTION OF THE MUSCOGEE QUADRANGLE

By Joseph A. Taff.

INTRODUCTION. The Ozark Plateau is limited, approximately, on removed, leaving broad, flat surfaces of deeply on the west by the Prairie Plains across the the north, east, and south sides by Missouri, Mis­ weathered chert. western part of the Choctaw Nation, Ind. T. LOCATION AND AREA. sissippi, and Arkansas rivers, respectively. On The third plateau is that of the Boston Moun­ The Arkansas Valley is made up of a great The Muscogee quadrangle is bounded by paral­ the west its border is followed closely by Neosho tains, which rise back of and above the Springfield thickness of sandstone and shale formations of lels of latitude 35° 30' and 36° and by meridians (or Grand) and Arkansas rivers in Indian Terri­ plain. These mountains are not well defined, but the Pennsylvanian series. These beds have been of longitude 95° and 95° 30' and contains 968.7 tory, and in part by Spring and Osage rivers in may be said to extend from the Mississippi low­ thrown into many folds, which together make a square miles. It is located in the Cherokee and Missouri. White, Black, St. Francis, Meramec, land, northeast of Little Rock, westward into deep structural trough corresponding with the Creek nations, Indian Territory, approximately and Gasconade rivers have their sources in the Indian Territory, ending near the southeast corner Arkansas Valley and extending from eastern the eastern two-thirds being in the former, and plateau near the main watershed and flow out of of the Muscogee quadrangle. Indian Territory to the Mississippi embayment its southern boundary is within a few miles of the plateau through narrow, deep, and crooked The Boston Mountains rise above the Springfield opposite Little Rock. These folded rocks were the Choctaw Nation. Its name is taken from valleys. plain on the south. They reach higher elevations beveled off by erosion until their edges formed Muscogee, the principal town in the Creek Nation, Considered in a broad sense the Ozark region is than any other part of the Ozark highland, but a peneplain now standing approximately 800 feet which is located near the junction of Verdigris made up of three dissected plateaus, the general become lower westward from near the Arkansas- above sea level. A few exceptions to this general and Neosho rivers with Arkansas River. character as well as the topographic detail of Indian Territory line. Viewed from eminences on statement may be noted in some of the broader which is dependent upon the kinds and atti­ the Springfield plain the Boston Mountains have synclinal folds in the south side of the valley. PHYSIOGRAPHIC RELATIONS. tudes of the rocks. These plateaus succeed ^one the appearance of a bold, even escarpment with a Protected by massive sandstone strata, whose The Muscogee quadrangle may be separated, another concentrically westward from the St. level crest. Actually, however, instead of having resistance to erosion was aided by their attitude in . physiographically, into two nearly equal parts, Francis Mountains as a center. They cross the an even northward front, this escarpment sends out the broad, basin-like folds, the rocks in such places .one of which belongs to the physiographic prov­ axis of the Ozark uplift and the main divide, finger-like ridges and foothills, which descend by remain as conical mountains with crests 900 to ince of the Ozark Plateau, or highland, and the which nearly coincide, and are inclined in the steps as successively lower, hard rocks come to the 2000 feet above the surrounding plain. Such are other to that of the Prairie Plains. The two general direction of the dip of the strata. The surface. Toward their northern ends many of Sansbois, Cavanal, Sugar Loaf, and Magazine provinces meet in this quadrangle in a broad, physiography of the Ozark Plateau in Missouri these foothills are intersected, becoming flat-topped mountains, whose crests give some idea of the shallow basin occupied in part by Neosho and in has been clearly described by C. F. Marbut outliers on the Springfield plain. former high level of the whole region. Since part by Arkansas River. The Ozark Plateau is (Physical features of Missouri: Geol. Survey The rocks that cap the Boston Mountains and the development of this peneplain of the Arkan­ low and nearly flat in this, its extreme southwest­ Missouri, vol. 10, 1896). Geologic mapping by extend down the southern slope are the thick sand­ sas Valley the land has been raised and erosion ern part, where it approaches these rivers, and the Arkansas Survey disclosed the same features stones and shales of the Winslow formation. The has cut more rapidly into the shaly beds, leaving from them the Prairie Plains rise gradually in their southern extension in Arkansas (Arkan­ sandstones, being the more resistant to erosion, form the sandstones, which make low, narrow, and toward the west. Brief descriptions of the salient sas Geol. Survey, vol. 4, 1890). the salient features of the mountains. The beds of sharp-crested, but generally level, ridges. In many topographic features of the Ozark Plateau and of The first of these plateaus has been termed by hard sandstone near the middle of the formation, of the smaller synclinal folds remnants of sand­ the Prairie Plains will assist in making clear the the Missouri Survey the Salem platform. It make the tops of the ridges in the middle and upper stone beds cap low buttes and hills in the general topography of the Muscogee quadrangle. occupies southeastern Missouri and a large part courses, but in the southern slopes shaly strata level of the peneplain. This peneplain extends of northeastern Arkansas. The magnesian lime­ higher in the section occur, so that the Boston westward into the region of the Prairie Plains. OZARK MOUNTAIN REGION. stones, cherts, and saccharoidal sandstones of the plateau is approximately a structural plain. Struc­ The crests of the hills in the southern part of the The Ozark region is a broad, relatively flat, Cambrian and Ordovician systems underlie this turally the mountains are monoclinal, with gradu­ Muscogee quadrangle west of Arkansas River dome-shaped, dissected highland. In parts of plateau, and slope gently away from the St. Fran­ ally increasing steepness of dip toward the south. mark levels in this peneplain. The flat valleys of this region, notably the southern and the east­ cis Mountains. The edges of these lower deposits The Boston Mountains are deeply dissected by the larger streams and the alluvial lands of Arkan­ ern, the greater elevations attain considerable form distinct escarpments facing the lowlands streams. Some of these flow down the southern sas River are in the lower plain, being developed prominence and are widely known as the Bos­ surrounding the St. Francis Mountains. Higher slopes; others have eaten, by headwater erosion, on the softer rocks. ton and St. Francis mountains. Elsewhere there formations of limestone and chert crop out in into their northern border. The crests of the PRAIRIE PLAINS. are numerous lower elevations, remnants of dis­ succession farther away, making subordinate plat­ numerous ridges, which slope southward from sected subordinate plateaus, to which names have forms and escarpments. The intervening softer the main divide to the border of the Arkansas The Prairie Plains include a broad region which been given and which are locally called moun­ saccharoidal sandstone beds occur in the lower Valley, define what may properly be called an rises in a gradual slope from the Ozark Plateau tains, although they do not generally deserve back slopes of benches and in the bases of the inclined plain or sloping dissected plateau. westward across Indian Territory until it merges recognition as such. In general geography the escarpments. The Salem platform is in general Near the east end of the Boston Mountains, into the plateaus of the Great Plains. Southwest- region is known as the Ozark Mountains, but deeply cut by stream erosion and the tops of where the capping sandstone formations are thicker ward it extends across central Texas and north­ the name has not been applied to any mountain the higher ridges and hills of its dissected escarp­ and lie more nearly horizontal and where White ward and eastward through eastern Kansas, north­ or definite collection of mountains in the province. ments stand at the same general level. Thus River in its deep valley approaches its northern ern Missouri, and beyond to the plains of the Fig. 1 shows the main physical features of the the Salem platform has been developed on the front, the escarpment attains its greatest height. Great Lakes. In Indian Territory it is a rolling region and the location of the Muscogee quad­ truncated edges of a number of formations. Here high, flat-topped, precipitous ridges, 1000 to or undulating land interspersed or broken by rangle. Back of the Salem platform, surrounding it on 1500 feet high, project northward on a level with northeast-southwest ridges and hills. The ridges the north, west, and south, lies an even structural the mountain top, making a high and ragged are characterized by a bench-and-terrace or table- plain of chert and limestone, named by Marbut escarpment. Farther west, toward the Arkansas- land-and-escarpment form of topography. The the Springfield structural plain, which has been Indian Territory line, the Winslow formation, escarpments and terraces face eastward and the developed on the surface of the Boone forma­ especially in its sandstone beds, becomes thinner table-lands and benches slope gently to the bound­ tion. Its inner border south of Osage River is and more shaly, and in proportion as it changes in ing plain. The rocks of this region in Indian marked by a pronounced escarpment the exposed thickness and nature the Boston Mountains decrease Territory are chiefly soft shales in which lie beds or edge of the Boone formation, wfyich overlooks the in elevation and in distinctness of topographic form. formations of hard sandstone, the whole dipping Salem platform. The Springfield plain slopes west­ Northward, beyond the west end of the mountains, at a low inclination westward, in a direction oppo­ ward at low angles in Missouri and farther south the change in the character of the rocks and in the site to the general slope of the plains. The thick­ and west, in northern Arkansas, following the dip topography is pronounced. In the Muscogee quad­ ness of these sandstone deposits varies, decreasing of the formation. In Missouri, Coal Measure shales rangle the Winslow formation is 800 to 1000 feet northward along the outcrops. With the change succeed the Boone formation, producing lowland. thick and the Boston plateau is not conspicuous, in thickness there is a gradual diminution of the In northeastern Indian Territory and Arkansas being represented by low, sloping table-lands with prominence of the ridges and of the bench and alternating formations of limestone, shale, and northward-facing escarpments. Farther north, on terrace features of the topography. The main sandstone occur above the Boone formation in the east side of Neosho River, the Winslow for­ drainage channels trend eastward with the slope of s s. low terraced hills and mountains that stand as mation gradually decreases in thickness and in the plains, and many of the smaller streams have Atd remnants above the Springfield structural plain. hardness of beds until it loses its identity in the cut by headwater erosion into the table-lands and benches, giving tortuous outlines to the escarp­ FIG. 1. Diagram showing relations of Ozark region to sur­ Such topographic features may be seen at the bor­ northeast corner of Indian Territory. Correspond­ rounding physiographic provinces and principal divisions ders of the Boone formation, in the northeastern ingly, the topographic form changes from. the low, ments. The western half of the Muscogee quad­ of the region. part of the Muscogee quadrangle. The Spring­ westward-sloping, dissected plateau to the lowland rangle illustrates the Prairie Plains topography in Location of Muscogee quadrangle is indicated by the small rectangle. field plain is also deeply dissected by the larger plain bordering the Springfield plain in the south­ Indian Territory. Physiographically, the Ozark region is bounded streams which flow through it in narrow, crooked eastern part of Kansas. as follows: On the north and west the low, valleys. Near the inner border of the Springfield TOPOGRAPHY. inclined upland grades almost imperceptibly into plain the 'Boone formation has been longer ARKANSAS VALLEY REGION. The topographic features east and west of the Prairie Plains. On the east the Mississippi exposed and is deeply corraded, giving the escarp­ The physiographic province of the Arkansas Arkansas and Neosho rivers differ markedly, lowland in southeastern Missouri and Arkansas ment a tortuous and ragged outline. Hills and Valley approaches the southern border of the the modified topography of the Ozark highland meets it along a sharp line, near which runs the buttes, cut off from the escarpments, stand oufon Muscogee quadrangle. It is bounded on the lying to the east and the various phases of the St. Louis, Iron Mountain and Southern Railway. the divides between the streams above the Salem north, as has already been stated, by the Bos­ Prairie Plains to the west. Neosho River and On the south the upland extends to the southern platform, their crests marking points in the former ton Mountains; on the south by the Ouachita Arkansas River below the mouth of the Neosho 'border of the Boston Mountains. In outline the extension of the Springfield plain. Between the Mountains of southwestern Arkansas and south­ have modified the somewhat indefinite boundary Ozark Plateau has rudely the form of a quad­ principal drainage lines lie large tracts of land eastern Indian Territory; on the east by the between the two provinces by\ erosion and have rilateral whose sides are nearly 225 miles in length. from which the younger formations have been Mississippi lowland at Little Rock, Ark.; and masked it with alluvial deposits. OZARK HIGHLAND. across it from the Springfield plain. The larger have not been deposited long enough to be appre­ northeastern part of the quadrangle, where much In the northeastern part of the Muscogee quad­ streams have cut relatively deep and narrow val­ ciably affected by erosion. Some of the high ter­ of it has been worn away. In the adjoining Tah­ rangle there are tracts of gently rolling land. These leys or canyons, such as that of the Illinois River races reach altitudes more than 150 feet above the lequah quadrangle erosion has gone through these areas are parts of the Springfield structural plain, in the southeast corner of the quadrangle. The present flood plain of the river, and have had devel­ Carboniferous rocks, exposing Devonian, Silurian, which has been developed on the Boone forma­ sources of these streams are among the detached oped on them distinct drainage and topographic fea­ and Ordovician strata in parts of the deeper val­ tion in northwestern Arkansas, southwestern Mis­ hills near the northern edge of the Boston Moun­ tures. Erosion of these terraces has advanced so leys, and the same pre-Carboniferous rocks have souri, and northeastern Indian Territory. On this tain plateau. The country between them is intri­ far that large parts of them have been removed and been cut through in drilling a deep well at Fort an exceedingly durable surface mantle of disin­ cately dissected and the small tributary streams, the remnants have been deeply etched by small Gibson, near the center of the Muscogee quad­ tegrated porous chert has been formed by weath­ which flow only during abundant rainfall, descend intermittent streams. rangle. ering. Waters falling upon it pass downward and in steep, sharp valleys. Illinois River has a steeper grade and a narrower A brief description of these rocks will probably gradually reach the valleys or issue in springs valley than the Arkansas. It approaches the latter be of service, especially in view of the active pros­ through subterranean solution channels. Thus PRAIRIE PLAINS. through the more elevated and hilly country of the pecting for oil now being carried on by deep-well only valleys of considerable size afford streams of The topography of the Prairie Plains in Indian Ozark highland, and its valley is canyon-like, typi­ drilling in the Muscogee quadrangle. The pre- sufficient power to corrade the fresh rock or even Territory is typically illustrated in the western cal of the larger streams of that region. Carboniferous rocks will be described in the order to remove the fragmentary chert. The result of half of the Muscogee quadrangle. The country in which they are encountered in drilling, begin­ these conditions is that broad, level tracts are west of Neosho River is an open, undulating DRAINAGE. ning with the Devonian. developed on the surface of the Boone formation. prairie. Thin sandstone and limestone beds in Four rivers drain the Muscogee quadrangle CHATTANOOGA SHALE. The hard sandstone beds of the Winslow forma­ the softer shales make low terraces and narrow the Arkansas, Verdigris, Neosho, and Illinois. tion thin out or give place to shales northward in benches which border the shallow valleys, but The largest is the Arkansas, which flows across The top of the Devonian is encountered at a eastern Cherokee Nation. As a result of this these terrace features are not sufficiently promi­ the central part of the quadrangle in a southeast­ depth of 800 feet in the well at Fort Gibson. The change in sediments, erosion has reduced large nent to be shown on the topographic map and erly course. From the Prairie Plains it flows rock is a black, slaty shale about 30 feet thick. areas in the northeastern part of the Muscogee are scarcely perceptible in a general view of the eastward, touches the southwestern border of the When dry or powdered it assumes a brownish- quadrangle to wide, shallow valleys having the rolling plain. Here and there a low butte or con­ Ozark highland, and then takes a southeasterly black hue. A bed of sandstone or conglomerate general level of the Springfield plain. The flat ical prairie hill is preserved by a capping of harder course. South of the southeast corner of the quad­ occurs in places at the base of the shale in the lands in the valleys of Greenleaf Creek east of strata. A typical instance is the conical hill 2 rangle the river turns eastward again and continues Tahlequah quadrangle. This local sandstone is Braggs, east of Fort Gibson, and on Fourteenmile miles west of Wagoner, upon which has been parallel with the southern boundary of the Ozark of the same age as the shale and is classed as a and Double Spring creeks are in this low plain. mounted a triangulation station. This rolling region to the Mississippi lowland. member of the formation. The formation has In the western part of the Ozark region this plain is prairie is characteristic of large areas of the The Verdigris River drainage lies within the been correlated with the Chattanooga black shale generally developed on the Boone formation, but in Prairie Plains in northern Indian Territory north Prairie Plains. Rising in Kansas, it flows in a of the southern Appalachian region and has been the northeastern part of this quadrangle it extends of the Arkansas and west of the Neosho, where southeasterly direction, joining the Arkansas near more fully described under this name in the Tah­ also over areas underlain by the Winslow, and may relatively few thick beds of hard rock occur in the the center of the Muscogee quadrangle. Like the lequah folio. be said to extend to Arkansas and Neosho rivers shales to interrupt the flat features of the land. Arkansas in the Prairie Plains region, it flows ST. GLAIR MARBLE. and to join the Prairie Plains through the valleys Farther south, however, along the strike of the across the strike of the rocks. of Bayou Manard and Fourteenmile Creek. rocks, the sandstone formations become, thicker Neosho River has its source southeast of the Beneath the Devonian black shale lies a forma­ It has been stated that the hard sandstone beds and harder. With the change in the sediments center of Kansas, near that of the Verdigris. Its tion of yellowish-blue and white marble, or lime­ of the Winslow formation constitute the salient sandstone ridges and hills rise higher above the course is southeasterly until it approaches the bor­ stone, 62 feet thick. It is supposed to be the same features of the Boston Mountains and of their general level of the plain. The broad stretches of der of the Ozark highland, near the northeast cor­ as the St. Clair marble, which occurs immediately lower westward extension, or foothills, in eastern rolling prairie immediately south of the Arkansas ner of Indian Territory. Touching the Ozark beneath the Chattanooga formation in the Tahle­ Cherokee Nation. The sandstone beds become Valley in the Muscogee and Okmulgee quadran­ highland here, it is deflected southward and fol­ quah quadrangle. Before the Devonian shale was thinner and more shaly westward to Arkansas gles decrease gradually in width southward until lows the highland border until it empties into deposited the rocks beneath it in eastern Indian River and thence northward east of Neosho River, they become narrow strips between belts of west­ the Arkansas near the center of the Muscogee Territory and northwestern Arkansas were folded and produce correspondingly reduced topographic ward-sloping timbered hills. In the Muscogee quadrangle. and then eroded to a generally flat surface. Near features. The crest of the Boston Mountain pla­ quadrangle the southward change in the topog­ Illinois River collects its waters entirely from Marble, in the southern part of the Tahlequah teau slopes westward from an elevation of 2000 feet raphy is seen west of Arkansas River. the Ozark highland. It rises in the northern quadrangle, the St. Clair marble appears to be not near the St. Louis and San Francisco Railroad in The district 8 to 10 miles in width about Musco­ foothills of the Boston Mountains, in northeastern less than 200 feet thick. It is entirely absent, Arkansas to 1600 feet near the Arkansas-Indian gee is an open, undulating prairie. The timbered Arkansas, and flows northward into the Spring­ however, from the lower Paleozoic outcrops near Territory line and to 900 feet in the southeast hills along the Arkansas southeast of Muscogee field plain, thence westward and southwestward, Tahlequah, and is generally lacking throughout corner of the Muscogee quadrangle. The west­ border it on the east, and eastward-facing, low with the pitch of the rocks, and enters the Arkan­ northwestern Arkansas and southwestern Mis­ ward extension of the Boston Mountain plateau in escarpments and flat-topped buttes bound it on the sas near the southeast corner of the Muscogee souri. Whether the frequent absence of the St. the southeastern part of this quadrangle is marked west, near the border of the quadrangle. Toward quadrangle. Clair marble is due to original local nondeposition by the crests of the flat-topped ridges and hills the south the river hills and escarpments converge The eastern part of the Muscogee quadrangle or to removal during periods of erosion preceding which slope southward and westward to the level until they approach on each side of Dirty Creek at is drained by Fourteenmile, Double Spring, and the deposition of the Devonian is a problem not of the Prairie Plains along Arkansas River. the southern border of the quadrangle. Greenleaf creeks, Bayou Manard, and Illinois yet solved. Remnants of the same plateau may be seen in Another band of flat prairie land lies parallel River, besides numerous small tributary streams. The St. Clair marble belongs to the Silurian the buttes and broken escarpments along the south to the escarpment of the Rattlesnake Mountains, The last three streams named flow directly into system. It was first described by the Arkansas side of the valley of Bayou Manard and between extending down the wide valley of Butler Creek. the Arkansas; Fourteenmile and Double Spring Geological Survey in 1890 (Ann. Rept., vol. 1, Bayou Manard and Fourteenmile Creek. Similar The Rattlesnake Mountains are a typical instance creeks are tributary to the Neosho. All these 1891) and named St. Clair, for St. Clair Springs, features, less pronounced, occur north of Fourteen- of the table-land and escarpment features of the streams are fed by springs that issue chiefly from north of Batesville, Ark., where it is well exposed. mile Creek. Prairie Plains in Indian Territory. The eastward- the Boone chert and are perennial except in times Near the middle of the Winslow formation there facing escarpment is abrupt, and the table-land, of extended drought. TYNER FORMATION. are some thick beds of hard sandstone which now which slopes westward with the general inclina­ The smaller streams in the western half of the Beneath the St. Clair marble in the Fort Gibson cap the higher ridges of the plateau. Where these tion of the rocks to a belt of rolling prairie that quadrangle drain the Coal Measure shales and sand­ well there is a formation consisting of greenish, beds have come to the surface there are small tracts crosses the southwest corner of, the quadrangle, is stones and are intermittent, their flow depending bluish, and reddish-gray shale and thin-bedded of table-land or flat benches. Similar phases of broken into lobes by streams that have cut through on the rainy season. During extended droughts sandstone, aggregating 116 feet in thickness. This topography occur where certain beds of hard sand­ it by headwater sapping of smaller drainage lines. the smaller drainage channels are almost entirely formation apparently corresponds to the Ordovician stone, at the base of the Winslow formation, cap Thus the harder formations of sandstone deter­ dry and the waters of the larger creeks stand in Tyner formation, described from outcrops on Illi­ the buttes and hills of limestone in the underlying mined the location of the table-lands and escarp­ isolated pools. nois River east of Tahlequah, where it is found to formation. These topographic details may be noted ments, and the shale outcrops coincide with the be essentially the same in character and in thick­ in the detached hills south of Bayou Manard and rolling or flat lands and with the lower slopes of DESCRIPTIVE GEOLOGY. ness as at Fort Gibson. Some variable beds of Double Spring Creek. The lower sandstone mem­ the escarpments. limestone in the upper part of this formation con­ ber of the Winslow also makes the bluffy timbered All the rocks exposed in the Muscogee quad­ tain fossils of Trenton age. The formation has hills facing Arkansas River on the west side of RIVER VALLEYS. rangle are stratified deposits formed in Carbon­ received the name Tyner from a small stream near the valley south of Coata Creek. The sandstone The principal rivers in the Muscogee quadrangle iferous time. They are represented on the colum­ the northern border of the Tahlequah quadrangle, beds are thinner and the hills proportionately less are the Arkansas, the Verdigris, and the Neosho. nar section sheet, and their comparison with related on which it is typically exposed. prominent along the western border of the Neosho They have worn down their valleys to essentially rocks in northern Arkansas is shown in the cor­ River flood plain. From the bluffs overlooking the permanent low grades; that is, each river in any relation table. The structural relations of the BURGEN SANDSTONE. valleys of these rivers the surface slopes down with one part of its course is not eroding or cutting formations to one another and their composition Beneath the Tyner formation in the Fort Gibson the dip of the strata to the line of the Prairie Plains. down its channel more rapidly than in other parts, afford some idea of the geologic history of the well there is a deposit of light-gray to yellow sand The Morrow, Pitkin, and Fayetteville formations, and each is scarcely more than able to remove the region. The interpretation of the available parts 80 feet thick. This sand corresponds in character composed of resistant beds of limestone alternating sediments w'hich are being brought down and depos­ of this geologic record is given under the head­ and position with the Burgen sandstone, which with soft shale, form the lower northern slopes of ited by the floods. These rivers may be spoken of, ing "Historical geology," page 6. The determi­ underlies the Tyner formation east of Tahlequah. the Boston plateau and the outlying hills on the therefore, as graded streams. The transported sedi­ nation of fossils and the statements concerning It is massive and consists of round, limpid quartz Springfield plain. They produce minor though ments make relatively wide and almost flat plains, the age, classification, and correlations of the for­ grains loosely cemented together. No fossils have distinct bench-and-terrace forms of topography, and in these surficial deposits the streams mean­ mations resulting therefrom are the work of Dr. been found in the Burgen sandstone. Its age is which are not sufficiently large to be represented der back and forth, occasionally touching the older E. O. Ulrich. inferred from its stratigraphic position. It lies on a map having 50-foot contour intervals. rocks at the borders. STRATIGRAPHY. between the Tyner formation, which is of Trenton Throughout the Boston plateau in Arkansas the A large part of the surficial deposits in the or late Ordovician age, and the Yellville forma­ northward-facing escarpment is dissected by streams Arkansas Valley is above the river's present flood PRE-CARBONIFEROUS ROCKS. tion, which is of Canadian or early Ordovician age. which flow to the north. In Indian Territory, as plain. Numerous local terraces occur in the sur­ The oldest rocks exposed in the Muscogee quad­ A study of the St. Peter or "Saccharoidal" sand­ illustrated in the Muscogee and Tahlequah quad­ ficial deposits, the highest of which are above the rangle consist of Carboniferous chert and limestone, stone in northern Arkansas and Missouri, with rangles, the entire plateau district is dissected by highest points reached by the river at the present though surface exposures show little other than which the Burgen is correlated by Dr. E. O. Ulrich, streams which flow southward and southwestward time. The sediments in the lower of these terraces chert, which occurs in a number of areas in the causes him to class it as early Ordovician. 3

YELLVILLE FORMATION. going list includes the species most commonly Bryozoa and by the presence of Pentremites. The PENNSfLVANIAN SERIES. From the base of the Burgen sand down to the found; their association is decidedly indicative of fauna of this limestone is more closely related to MORROW FORMATION. bottom of the Fort Gibson well there are 78 feet of Keokuk age. that of the overlying Pitkin limestone than to that Variations. The Morrow formation as devel­ light-blue magnesian limestone. A formation of Thickness. The Boone formation at Fort Gib- of any lower beds, and were it not for the interven­ oped in this region consists of limestone and similar character occurs in northern Arkansas and son is estimated to be 184 feet thick, and probably ing black shale the upper limestone of the Fayette­ shale, with local beds of thin sandstone. The in Missouri beneath the St. Peter sandstone, to as much is exposed in the northeastern part of the ville formation would be included with the Pitkin. limestone greatly predominates in thickness. The which, as stated above, the Burgen sandstone in quadrangle, where the base is not reached. In The species of common occurrence in this upper shale occurs most abundantly in the upper part the Tahlequah quadrangle is believed to corre­ the Tahlequah quadrangle, where full sections are limestone are given in the foregoing list. of the formation, but is found in places both at the spond. This formation of magnesian limestone exposed, its thickness ranges from 100 to 300 feet. Name. The formation is named for the town of base and near the middle of the main body of contains fossils that have been classed as earlier Except in a few localities the top and base are sepa­ Fayetteville, in Washington County, Ark., and is limestone. The quantity of lime in the formation Ordovician in age. It has been named from the rated in outcrop by several miles, and the rocks are described in the Fayetteville and Tahlequah folios. decreases toward the east, and in the same direc­ town of Yellville and described by G. I. Adams in so concealed by surface chert debris that determina­ Thickness. The thickness of the Fayetteville tion there is an increase of both shale and sand­ 1904 (Zinc and lead deposits of northern Arkansas: tions of thickness are at best only approximate. formation is estimated to va.ry from 20 feet in its stone. The shale found locally at the base in the Prof. Paper U. S. Geol. Survey No. 24, 1904, pp. Name. The formation was named for Boone southern exposures to 60 feet in the northeastern Muscogee quadrangle becomes more sandy as it 18-20). County, in northern Arkansas, and was first part of the Muscogee quadrangle. Both the shale grows thicker, until, in parts of the Tahlequah

CARBONIFEROUS SYSTEM. described by Dr. F. W. Simonds in 1888 (Arkan­ and the included limestone beds vary in thickness. and in the Fayetteville quadrangle, it assumes the sas Geol. Survey, vol. 4, 1889). Toward the east the Fayetteville formation importance of a separate formation or member. MISSISSIPPIAN SERIES. changes in character. In the northeastern part In the Tahlequah and Fayetteville folios it is BOONE FORMATION. FAYETTEVILLE FORMATION. of the Tahlequah quadrangle and in the Fayette­ described as the Hale sandstone member of the Character. Only the upper part, probably 200 Character. The Fayetteville formation consists ville quadrangle the shale in the central and upper Morrow formation. In parts of the Fayetteville feet, of the Boone formation is exposed in the of dark-blue to black fissile shale, with usually part of the formation is lighter in color than it is and adjoining quadrangles the formation consists Muscogee quadrangle. The rocks consist, for the thin limestone beds. The larger part consists of in the Muscogee quadrangle and includes a thick almost entirely of shale and sandstone. Still far­ most part, of interstratified chert and cherty lime­ shale, in which the limestones are inclosed as thin lentil of sandstone called the Wedington sandstone ther east, in the vicinity of Yellville, the lime­ stone. At the base of the formation in the adjoin­ lentils or as beds locally variable in thickness. member. With the change in character eastward stone, it is reported, is entirely absent. As will ing Tahlequah quadrangle thin limestones free In the Muscogee quadrangle two of these beds of goes an increase in the thickness of the formation. be shown in discussing the relations of the Mor­ from chert occur locally, while at other locali­ limestone seem to be constantly present. One In the northeastern part of the Tahlequah quad­ row formation to contiguous formations, these local ties the chert rests on the Chattanooga black occurs at or near the base, another near the top of rangle the thickness is 170 feet and in the Fayette­ variations in the constituents of the Morrow appear shale without intervening limestone beds. This the formation. In many places where the rocks ville quadrangle it probably exceeds 200 feet. to be attributable chiefly to overlap and to varia­ lower limestone is thick enough to be classed as a are not well exposed the lower limestone appears There is apparent perfect conformity in the tions in character and amount of sediments accord­ member of the formation, and although not exposed to be in contact with the underlying cherty beds of Muscogee quadrangle between the Fayetteville ing to relative distances from the shore line at in this quadrangle, will be briefly described. It the Boone formation, the bed of shale that in more formation and the contiguous Boone formation which the sediments were deposited. consists of fine-textured, even-bedded, and dense, complete sections underlies the limestone being and the Pitkin limestone. Toward the east, in The main limestone, with its included shale, white to pinkish, marble-like limestone and light- absent. However, where the contact between the Fayetteville quadrangle and at other places constituting the lower and larger part of the for­ colored crinoidal limestone in beds aggregating 10 the Fayetteville and Boone formations was well in northwestern Arkansas north of the Boston mation, will be described as limestone of the Mor­ to 15 feet in thickness. Its position in the for­ exposed the shale was always found to be present Mountains, the basal shale is locally separated row formation. The succeeding shale, with its mation and its lithologic character strongly indi­ in greater or less amount. from the underlying Boone formation by the thin limestone and local sandy beds, will be dis­ cate that it should be correlated with the basal The layers making up this lower bed of lime­ Batesville sandstone. Where this sandstone is cussed as shale of the Morrow formation. St. Joe member of the Boone formation in the stone are mainly fine grained in texture and vary wanting it is considered that the shale rests on a Limestone of the Morrow formation. The main northern part of the Fayetteville quadrangle and from an inch or two to a foot or more in thickness. more or less eroded surface of the Boone. In the limestone of the Morrow formation consists of rel­ farther east in northern Arkansas. Near the Their color varies from light to dark blue, or even Muscogee quadrangle the even contact between atively hard, blue, fine-textured rock. Usually in northern boundary of the Tahlequah quadrangle, black when fresh, but the weathered surface of the the Fayetteville formation and the overlying Pit- the middle part a deposit of blue clay shale occurs, in the east side of Illinois River Valley, also, rock commonly displays shades of drab or yellow­ kin limestone appears to be perfectly conformable. interbedded with which here and there are thin there are basal beds which consist of dull-blue, ish blue. The thickness of the whole bed ranges sandstone and limestone layers. In places shale PITKIN LIMESTONE. earthy, fossiliferous limestone in the lower part, from 5 to 15 feet. These extremes were observed also occurs near the top of the member, inter­ on which rest beds of thicker and harder lime­ in near-by exposures in the northeastern part of The Pitkin limestone consists of light-blue to bedded with the limestone; in such places there is stone, the whole aggregating 6 feet in thickness. the quadrangle. brown, granular, earthy, slightly oolitic strata a gradation from the limestone into the shale These beds contain fossils of Kinderhook age, and Fossils. Fossils are extremely rare in the shale, interbedded with fine-textured massive layers. above. Again there is an abrupt change upward according to this classification lie at the base of but the limestone beds generally afford a varied The granular and oolitic types of rock are the from limestone into shale. the Boone formation. They are, however, too and abundant fauna. The following list includes more common and may be said generally to char­ Some layers of this important limestone member thin and limited in exposure to justify separate the names of the principal fossils of the lower acterize the formation. The thickness of beds are full of small gasteropods and pelecypods, of description and name. limestone bed: is variable, ranging from thin platy strata to beds species mainly undescribed. Other layers are The upper bed of the St. Joe member is a lighter- A large undescribed crinoid, related to Eupachycrinus but 1 or 2 feet thick. The thinner strata are usually charged with many kinds of Bryozoa. These, also, colored, often pink, and generally crystalline cri­ having uniserial arms. The plates of the calyx, being thick more argillaceous, and thin shale layers not uncom­ are nearly all new to science, but when compared noidal limestone, which, together with the lower and bulbous, are striking fossils. monly separate them. with known species their alliances are in nearly Productus unnamed species of the type of P. splendens. part of the cherty limestone overlying it, contains Camarotoechia sp. undet. The Pitkin limestone is considered to be the every case nearer Pennsylvania!! than Mississippian a Burlington fauna. Archimedes cf. A. communis Ulrich. top of the Mississippian series of the Carboniferous. types. A subramose Michelinia (near eugenece Orthothetes kaskaskiensis McChesney. The succeeding cherty limestone constitutes almost Chonetes n. sp. of the type of C. geinitzanus Waagen The fossils listed as from the upper limestone of the White) is abundant, also another coral comparing the whole of the Boone formation and is the part (rare). Fayetteville formation are equally characteristic of rather closely with Trachypora austini Worthen. exposed in this quadrangle. The exposed beds Productus cf. P. cora and P. tenuicostus. the Pitkin. Both of these corals are of service in distinguishing Productus cestriensis Worthen. are made up essentially of calcareous chert or Seminula subquadrata Hall. In thickness the Pitkin limestone in the Mus­ the horizon from the lithologically similar Pitkin flint, with variable bands or beds of limestone. Cleiothyris sublamellosa Hall. cogee quadrangle varies but little from 50 feet, limestone. Among the brachiopods, which class is Spirifer increbescens Hall. Fresh exposures occur in but few places. They Spirifer of the type of S. pinguis; cf. S. scobina Meek. such slight changes as probably occur being due represented by a number of undetermined species, are found in steep bluffs and cliffs where the Spiriferina transversa McChesney. to erosion of its upper beds prior to the deposition a Hustedia (cf. mormoni Marcou) affords perhaps larger streams meander against the sides of their Dielasma cf. D. formosum Hall. of the overlying formation. Where the shaly bed the most reliable evidence of the Pennsylvania!! valleys or, more rarely, in the beds of the smaller Of the above list the first three are very abun­ is concealed the boundary between the Pitkin and rather than the Mississippian age of the Morrow streams, in their middle or lower courses, where dant and characteristic. Morrow formations is difficult to determine with­ formation. Several very fine species of crinoids the grades are sufficiently steep and the volume of The upper limestone bed is thin, rarely exceed­ out a careful study of the fossils in the limestones occur in the lower limestone, but as they are all water is great enough to induce active erosion. The ing 3 or 4 feet, and occurs about 10 feet below the both above and below the contact. In places shale, new they throw very little light on the age of the chert element is so much more abundant than the top of the shale. It is argillaceous and more or and in other localities sandy shale as well, may be bed. The generic types represented occur in late limestone and is so resistant to the effects of erosion less ferruginous, and weathers in thin, hackly slabs found above the Pitkin limestone. This represents Mississippian rocks .and, in part at least, in much that almost the entire surface rock consists of angu­ or plates. Many of the layers are composed prin­ the Hale sandstone member of the Morrow forma­ later Pennsylvania!! deposits. However, so few lar chert bowlders and fragments. cipally of fossil shells, which weather unequally tion, which is well developed in the Tahlequah crinoids are known from the latter series that it is In the deep well at Fort Gibson the Boone with the ferruginous and argillaceous matrix. quadrangle and farther east in Arkansas. not yet possible to estimate properly their value as formation consists of light- to dark-blue siliceous Such beds disintegrate to lumpy masses or slabs The Pitkin limestone crops out generally at the evidence of the age of the rocks. Pentremites rus- and argillaceous limestone, with 20 feet of light- of loosely cohering shells and fragments of fossils. bases of hills and in steep slopes, bluffs, and ticus Hambach is one of the common fossils. It is gray limestone at the base. The samples of drill­ The. rock when fresh is bluish in color, but changes escarpments of the higher Morrow and Winslow from this fossil that the old name of the member, ings obtained from the well indicate that the char­ to yellowish brown on weathering. ' formations, the talus from which frequently con­ Pentremital limestone, described as a formation by acter of the surface rock has been produced by The fossils of the upper limestone are distin­ ceals the contact. Toward the east,' bevondv the the Arkansas Geological Survey, was derived. the removal of a large part of the original lime guished from those of any part of the formation Tahlequah quadrangle, the Pitkin limestone occurs The limestone of the Morrow formation is locally by solution and by segregation of the silica as below by the greater abundance and variety of in isolated areas and crops out along the northern variable in thickness. In places some of the upper chert. foothills of the Boston Mountains in northwestern beds were removed by erosion prior to the deposi­ Fossils. The cherts in the upper part of the Pentremites sp. undet. (a large form between P. godoni Arkansas. Typical exposures occur in the north tion of the succeeding Winslow formation, but the formation are locally very fossiliferous. The fore- and P. conoideus). slopes of the Boston Mountains near Pitkin, on variations -are not due in all instances to such Septopora cestriensis Prout. Fenestella sp. nov. (a common Chester form). the St. Louis and San Francisco Railroad, from removal. South of Manard the limestone is 100 Amplexus fragilis White and St. John. Archimedes compactus Ulrich. which place the name of the limestone*has been to 150 feet thick. The shale that belongs above Grlyptopora keyserlingi Prout. Archimedes communis Ulrich. taken. The formation was described by Dr. the limestone was found in this district wherever Fenestella multispinosa Ulrich. Archimedes intermedius Ulrich. Polypora maecoyana Ulrich. Archimedes swallovanus Hall. F. W. Simonds (Arkansas Geol. Survey, vol. 4, exposures could be noted. The thickness decreases, Hemitrypa proutana Ulrich. Polypora corticosa Ulrich. 1889), by whom it was called the Archimedes though not regularly, toward the northeast. On Pinnatopora striata Ulrich. Productus cestriensis Worthen. Spirifer logani Hall. Productus spv of the type of P. cora. limestone. Archimedes, the generic name of one Neosho River, near the east side of T. 16 N., R. 19 Retieularia pseudolineata Hall. Productus sp. of the type of P. punctatus. of the characteristic fossils, not being an appro­ E., the limestone is nearly 100 feet thick. Here Productus setigerus Hall. Seminula subquadrata Hall. priate designation for a formation, a name of the sandstone beds of the succeeding Winslow for­ Orthothetes keokuk Hall. Reticularia setigera Hall. Capulus equilaterus Hall. Spiriferina spinosa N. & P. geographic significance has been substituted. mation rest on the limestone, the shale that usually Muscogee. intervenes having been removed, it is presumed, Muscogee quadrangle doubtless are to be correlated uppermost beds extend from the top of the low in alternate strata, and the shale in the aggregate prior to the deposition of the Winslow sediments. with the sandy shale forming the lower part of the escarpments down to the wide valley at the base is thicker than the sandstone. There are twelve Near the northeast corner of the quadrangle the Hale sandstone member in its typical exposures. of the Rattlesnake Mountains and to Butler Creek, or more groups of sandstone beds separated by thickness of the limestone is reduced to nearly 50 The upper part of that member, however, is always toward the northwest. The thickness of these thicker deposits of shale which include thin sand­ feet. The same conditions occur near the bound­ more or less calcareous and locally includes real sandstone beds, with their included shales, near the stone and shaly sandstone strata. ary of the quadrangle, farther south, in Tps. 16 limestone, and may be provisionally correlated southern boundary of the quadrangle is estimated In the Muscogee quadrangle only the lowest and 17 N., R. 22 E. with the lower part of the main limestone of the to be more than 100 feet. Toward the northwest sandstone and its inclosing shale members are Shale of the Morrow formation. The deposits formation in the Muscogee quadrangle. Accord­ the sandstones become thinner and softer and it is exposed. The basal deposit is a comparatively above the main limestone consist of blue and black ing to this interpretation, only the upper part of the believed that they can not be traced north of soft shale, approximately 200 feet thick. The shale, with thin beds of limestone and sandstone main limestone is the equivalent of the Pentremital Arkansas River. overlying sandstone is a gray to yellowish-brown locally developed and more rarely with thin coal limestone of the Arkansas Survey and the Brent- From the top of the upper group of sandstone rock, and occurs for the most part in thick or in the lower part. The thin limestones and the wood member of the Morrow formation, described beds shale continues to the top of the formation. massive and moderately hard beds. The lower shales interbedded with them are usually light in the Fayetteville folio. The lower part of the Locally variable shaly sandstone beds and beds of sandstone beds are usually exposed in cliffs and blue and weather to shades of yellow. They shale, which contains the local coal beds, is the thin coal occur in the shale. Accurate determina­ bluffs at the crests of the escarpments which they resemble the limestone and associated shale lower "Coal Bearing shale" of the Arkansas Geological tions could not be made, but it is estimated that produce. The upper layers make flat and gently in the formation. The shale in the lower part of Survey report. The thin limestone in the upper the thickness of this shale does not exceed 100 feet. rolling tracts of sandy loam which slope westward this upper member is darker in color and that asso­ part of the Morrow is to be correlated with the This shale is the westward continuation of the from the escarpment of the Rattlesnake Mountains. ciated with the coal is black, being impregnated with Kesler limestone of the same report. Akins shale member of the Winslow formation, Toward the northwest this sandstone gradually bituminous matter. described in the Tahlequah folio. grows thinner, more shaly, and softer, the decrease The fauna from the upper thin limestone and WINSLOW FORMATION. Name. The Winslow formation is named for a in thickness and the change in character being sandy beds of the Morrow consists for the most Character. The Winslow formation consists of town located at the crest of the Boston Mountains emphasized by the topographic expression of the part of brachiopods and bryozoans. All the forms bluish and blackish clay shale, sandy shale, brown on the St. Louis and San Francisco Railroad, in rock. Near the southern boundary of the quad­ observed occur also in the main limestone below. sandstone, and thin beds of coal. The sandstone northwestern Arkansas. The greatest development rangle the sandstone is marked by the strong Essentially a single fauna pervades the whole beds for the most part occur in two groups, one of the formation, especially that of the sandstone escarpment and timbered table-land of the Rattle­ formation. near the base and the other above the middle of deposits in the lower part, occurs in the Boston snake Mountains. Northwestward the escarpment The shale in the upper part of the Morrow for­ the formation. Mountains. The Boston Mountains are the phy­ becomes gradually lower and less distinct, until it mation is usually concealed by sandstone debris The rocks near the base and below the lower siographic expression of the Winslow formation. is lost in the rolling prairie north of Oktaha. The and overwash of soil from the overlying Winslow body of sandstone are interstratified sandstone and Thickness. The thickness of the Winslow for­ lowest shaly strata, lying above the sandstone, formation. It crops out near the hilltops or in shale beds. The sandstones are for the most part mation in the quadrangle is estimated to be 800 to occur in the southwest corner of the quadrangle. the sides of valleys near the sources of drainage thin or shaly, but in places are thick and mass­ 1000 feet, but an accurate determination of its A bed of bituminous coal, 2 feet 6 inches thick, channels. In consequence of these relations esti­ ive and occur at the base in contact with the thickness is not possible where the rocks are occurs in this shale near the base. It should be mates of its thickness can be but roughly approx­ limestone of the underlying Morrow formation. inclined at low angles, where dips are variable, found to crop out across the southwest corner of imate. In places the massive sandstone of the Locally they are coarse grained at the base and or where the strata in large measure are obscured the quadrangle. Winslow formation rests on the limestone belong­ may contain small rounded pebbles of quartz. by soil. Toward the west and north it becomes Name. The Boggy formation was named for ing below the shale; at others a belt of sloping This pebbly character increases eastward until, in thinner. Near the Arkansas-Indian Territory Boggy Creek, in the Choctaw Nation, and has been clay soil, from which thin ledges of limestone pro­ the northern foothills of the Boston Mountains of boundary, 25 miles east of the Muscogee quad­ described in the Coalgate and Atoka folios of the ject, ranging from a narrow strip to a slope 40 feet northwestern Arkansas, the rocks become conglom­ rangle, it is estimated to be not less than 1500 feet United States Geological Survey. It has large in height, indicates the thickness of the upper shale eratic. It may be said that these alternating sand­ thick. Strata equivalent to the Winslow and sev­ exposures on Boggy Creek in the Coalgate quad­ member of the Morrow formation. stone and shale beds culminate in the thicker sand­ eral higher formations, aggregating several thou­ rangle and attains there a maximum thickness of Name. The Morrow formation is named for the stone deposits which lie 200 to 400 feet above the sand feet in their exposures along Canadian River, over 2000 feet. Only the lower part of the Boggy village of Morrow, near which a typical section of base of the formation. These sandstone beds grad­ decrease in thickness northward until they do not formation, having an estimated thickness of 500 the rocks is exposed, in Washington County, Ark., ually become thinner toward the north, and at the exceed 500 feet at the Indian Territory-Kansas feet, is exposed in the Muscogee quadrangle. about 5 miles east of the Indian Territory line. same time the amount of lime in the shale increases, boundary. In the Kansas section the Winslow Correlation. The greatest development of the Relations to contiguous formations. The strati- so that parts of it become very calcareous and it con­ formation is represented in the lower part of the sandstone members of the Boggy formation is graphic relations of the bottom and top of the Mor­ tains beds of shaly limestone. Cherokee shales. found along the Canadian River Valley in the row formation to the underlying Pitkin limestone The sandstone deposits have their strongest topo­ Correlation. Southward the Winslow formation Canadian quadrangle, which adjoins the Muscogee and the overlying Winslow sandstone, respectively, graphic expression in the southeastern part of the descends beneath the surface in the deep trough of quadrangle on the southwest. From the Canadian seem always to be more or less unconformable, with­ quadrangle, where they are thickest. The beds of the Arkansas Valley, which lies south of the Mus­ Valley, both toward the southwest and northeast, out, however, in any case exhibiting any marked heavy sandstone in the upper part of the series cap cogee quadrangle. Where it rises in the south there is a gradual thinning of the sandstone beds discordance of stratification. That the relations the local table-lands east of Illinois River and the side of the Arkansas Valley trough and against and of the formation as a whole. In both direc­ are unconformable is generally determinable only timbered hills lying along the west side of Arkan­ the Ouachita Mountain region in central Choctaw tions there is an introduction of limy strata in the through comparisons between the beds on either sas Valley from the southern border of the quad­ Nation, the section has increased to an estimated shale, with thinning of the sandstones. This thin­ -side of the contacts in separate exposures. rangle to a point opposite Muscogee. Farther thickness of 8000 feet. Here the stratigraphic ning of the sandstones or their gradation into shaly At and south of Fayetteville the Hale sandstone, north and east of Arkansas and Neosho rivers and representatives of the Winslow are divisible into deposits becomes so pronounced farther north that at the base of the Morrow formation, is an impor­ bordering the valley of the latter the topographic three formations, named the Atoka formation, the the formation can not be distinguished north of tant member. The relatively small amount of sili­ features incident to these sandstone beds are less Hartshorne sandstone, and the McAlester forma­ Arkansas River. Formations lying above the ceous sand it contains in the Muscogee quadrangle pronounced. The forest also, which is influenced tion. These formations have been mapped through Boggy have been traced' from Arkansas River to and the increasing prevalence of such material in by the occurrence of the sandstone, becomes grad­ their entire extent in the Choctaw Nation and have the Indian Territory-Kansas line, showing that the more easterly and northerly outcrops point to ually thinner northward and is interspersed with been described in the Coalgate and Atoka folios the 2000 feet or more of the Boggy formation in the Ozark region, which at that time was land, as prairie on the uplands. and in papers on Indian Territory coal published the Canadian River Valley must be correlated with the main source from which the clastic elements On the lower group of sandstone and shaly beds in the Nineteenth, Twenty-first, and Twenty-second a part of the Cherokee shales of southeastern Kansas. of the formation were derived. rests a deposit of shale composed chiefly of clay. Annual Reports of the United States Geological QUATERNARY SYSTEM. The unconformity at the top of the Morrow for­ Locally sandy shale or thin sandstone may occur in Survey. The McAlester formation is exposed mation seems to be greater in the Muscogee quad­ this position, but not of sufficient thickness or hard­ across the Arkansas Valley trough and is found TERRACE SAND. rangle than in the more eastern localities where ness to become apparent in the surface of the land. to be equivalent to the part of the Winslow forma­ At the borders of the immediate valleys of the contact with the Winslow has been observed. The shale dips approximately 2° toward the south­ tion in the Muscogee quadrangle that extends from Arkansas and Neosho rivers, above their flood Here the upper Morrow beds, that is, the strata above west in the southern part of the quadrangle, and its the top down to the lower group of sandstones plains, lie surficial deposits of gravel, sand, and the main limestone, are locally absent. While the outcrop is limited to the valley of Dirty Creek. 200 to 400 feet above the base. The stratigraphic silt. Along the Arkansas Valley these deposits upper shale member ranges from a knife edge to Toward the middle and in the northern part of the relations between the lower 200 to 400 feet of the consist of fine yellow sand and silt, with small only 40 feet in thickness in the exposures studied quadrangle the dip of the rocks becomes less and Winslow formation in the Muscogee quadrangle quantities of quartzose gravel locally in the lower in the Muscogee quadrangle, it is not less than 140 the sandstone both above and below decreases in and the Atoka and Hartshorne formations, aggre­ part or at the base. The coarser sand is found in feet in the Fayetteville and Winslow quadrangles thickness, so that the surface extent of the shale gating more than as many thousand feet, can not the central parts of the areas and in the sides and at least 275 feet in the southern part of the can not be outlined. A thin coal which occurs in be ascertained, because these rocks have not yielded toward the river, and resembles in all respects that Yellville quadrangle. Part of this inequality in the upper part of this shale has been prospected fossils for accurate comparative studies. now being transported by Arkansas River. thickness is doubtless due to the diminution west­ near the source of Spaniard Creek and on Sam The McAlester formation in the Sansbois quad­ Near the borders of the terrace deposits farthest ward of the quantity of the clastic material derived Creek south of Muscogee. Thin coal beds, pre­ rangle, which adjoins the Muscogee quadrangle, is from the river the sand grades into silt which is from the Ozark land of the time, but the greater sumably in the same shale, have been prospected 2 overlain by the Savanna formation. South of scarcely distinguishable from the light sandy loams part must be ascribed either to nondeposition or miles south of Wagoner. Like the deposits lower Sansbois Mountain the Savanna is approximately vresidual on Carboniferous rocks. These sands and to erosion, or to both. In any event a considerable in the formation, the shale becomes more limy 1000 feet thick. Its thickness becomes gradually silts are porous, nonindurated deposits and are hiatus between the Morrow and Winslow forma­ northward. Limestone beds, probably of local less toward the north, until the sandstone beds easily transported, even by the smaller rivulets. tions is indicated in the Muscogee quadrangle. extent, occur in the vicinity of Wagoner, and contained in it are lost to view near the southern As a result the upper, finer sands often conceal by Correlation. The Morrow formation in the others are reported to have been penetrated by boundary of the Muscogee quadrangle. This for­ overwash the lower parts of formations and their Muscogee quadrangle includes stratigraphic rep­ drills in deep wells at Muscogee. mation not being distinguishable, the top of the basal contacts. resentatives of a group of rocks which were sepa­ The upper group of sandstones consists of yel­ Winslow formation, being stratigraphically the The terrace deposits at the border of the Neosho rated into four formations in northwestern Arkansas lowish-brown beds interstratified with bluish clay same as the upper boundary of the McAlester, River Valley locally contain chert and sandstone by the Arkansas Geological Survey (Ann. Kept., shales. These beds are in part ferruginous and are seems to be in contact with the overlying Boggy gravels, derived from the Boone chert and the vol. 4, 1888). The lowest of these, called the generally soft, except where segregations of iron formation. overlying Carboniferous rocks contiguous to the Washington shale and sandstone (a preoccupied have locally indurated the rock. The uppermost valley of Fourteenmile Creek. Gravel of the same BOGGY FORMATION. name), is described in the Fayetteville and Tah- beds are thickest; these cap the escarpments and class, with less sand associated, occurs on the north lequah folios as the Hale sandstone member of the low hills that mark the outcrops of the deposits west Character. The Boggy formation is composed side of Fourteenmile Creek across T. 17 N., R. 20 Morrow formation. The locally sandy shales occur­ of Dirty Creek and those at the sources of Spaniard, of bluish clay shale, sandy shale, and gray or E., and extends upward from the valley to an ele­ ring at the base of the Morrow formation in the Sam, and Pecan creeks. The low dip slopes of the brown sandstone. The shale and sandstone occur vation of nearly 100 feet above the stream. It occurs as a thin mantle or in local patches spread and faulting occurred in a short interval, even sas and Neosho rivers follow approximately the center of the main fold. In the strike of the most over the Carboniferous rocks. of geologic time. Instead, it is most likely that line between the two structural divisions. When southerly fault, extending southwestward from its These terrace sands and gravels extend from the the deformation of the rocks has been going on viewed broadly the rocks in the quadrangle are end to Arkansas River, there is a distinct anticline. borders of the river bottoms upward more than at various ages since the Carboniferous and that seen to be tilted southwestward. In the eastern In this fold the rocks in the southern limb are 100 feet. The sand between Arkansas and Verdi­ movements have occurred, especially in the eastern half the average inclination is less than 20 feet per more steeply tilted than those in the northern gris rivers occupies the watershed between these part of the quadrangle, in relatively recent time. mile. Near Arkansas and Neosho rivers the mon­ limb, although the rocks near the quadrangle bor­ streams for over 9 miles. These sands have been Two structural provinces are represented in the oclinal tilting is increased to 100 feet or more per der are thrown downward toward the north. deposited a sufficient length of time to have had Muscogee quadrangle. One of these is the Ozark mile, and this inclination continues to and beyond Toward the southeast in this fold the dips of developed on them a pronounced erosion topog­ uplift, corresponding to the physiographic prov­ the southwest corner of the quadrangle. the rocks gradually decrease to the corner of raphy. The larger streams have worn down chan­ ince of the Ozark highland; the other is the /Structure sections and maps. To aid in giving the quadrangle. nels to a depth of 50 to 100 feet and the small Prairie Plains in northern Indian Territory, of an understanding of the structure of the quadran­ A number of faults occur between the valleys of tributaries have obliterated the level of the original monoclinal structure. A brief outline of the gle a structure sheet has been prepared, showing Fourteenmile and Double Spring creeks and the flat surface. Ozark uplift and the monoclinal Prairie Plains the geology of two sections, one drawn across the northern boundary of the quadrangle. These are \ Sand deposits of the same character have been will give a better understanding of the structure strike in a southwesterly direction, and the other peculiar in respect to their relations both to one mapped along Arkansas Valley in the adjoining of the Muscogee quadrangle. across the folded and faulted strata. These struc­ another and to the folding of the strata. Two of Sansbois and Ballisaw quadrangles, and similar ture sections show approximately the altitude of them, which cross the northwest corner of T. 17 deposits have been reported by the Arkansas Geo­ OZARK UPLIFT. the formations beneath the surface, though the N., R. 20 E., within about half a mile of each logical Survey to occur in the same valley in The Ozark uplift comprises southern Missouri, scale is too small to show the minor undulations other, are curved and are essentially parallel. The Arkansas. Terrace deposits of the same kind that part of Arkansas included in and lying north and details of folding. The sections show the downthrow of the more easterly one is toward the occur in elevated channels along Canadian, Wash- of the Boston Mountains and west of the Missis­ structure only near the line along which they southeast, while the displacement of the other is ita, and Red rivers. The sand in the Canadian sippi lowlands, northeastern Indian Territory east have been drawn, but will aid materially in the downward in the opposite direction, leaving an and Washita valleys is described in the Coalgate of Grand River, and the southeast corner of interpretation of the structure of the quadrangle as elevated block between them. To the east of these and Tishomingo folios. Terrace gravels and sands Kansas. In fig. 1 are outlined approximately the a whole. faults are two others, which are about a mile apart in Red River Valley continue southeastward, join­ physiographic divisions of the Ozark province. Folds and faults. The rocks in the eastern half and nearly parallel. The strata between these have ing extensive deposits of similar nature widely dis­ The boundaries of the uplift can not be clearly of the quadrangle, more particularly east of Arkan­ been moved downward with respect to the adjoin­ tributed over the Tertiary rocks of eastern Texas defined because of the gradual change in structure sas and Neosho rivers, have been thrown into rel­ ing rocks. This depressed block abuts against the and Louisiana. These gravel and sand deposits to. that of the border provinces of the Prairie atively wide and shallow, unsymmetrical, depressed elevated fault block just mentioned. The faults descend beneath the surface near the base of the Plains and that of the Arkansas Valley. The folds, which trend northeast and southwest. These on the south of each block join in a common frac­ Quaternary sediments bordering the Gulf coast. strata incline gradually downward on the north synclinal folds are separated or interrupted by nor­ ture, while the one on the north of the downthrown Since these terrace sands in the Muscogee quad­ and west beneath the Prairie Plains. The limits mal faults associated with incipient anticlinal folds area cuts across the faults bounding the elevated rangle are related in both composition and location are more distinct on the south, owing to the more or by unsymmetrical anticlines that in general block. to the sand transported by the river at the present abrupt change from the monocline of the Boston strike with and extend beyond the end of the Two other faults occur farther west, near Arkan­ time, it is concluded that they were laid down by Mountains to the folded rocks of the Arkansas faults. Where the folds and faults are associated sas River, and bear toward the southwest in the the meandering Arkansas when it flowed at eleva­ Valley. On the eastern border of the dome the it is necessary to describe them together. general direction of the dip. The larger and more tions 150 feet and less above its present level. structure is concealed for the most part by the The faults may be classified into two series or easterly of the two has thrown the rocks down northern extension of the Tertiary and the recent groups one in which the associated folds are more toward the east, while the downthrow of the other RIVER ALLUVIUM. flat sediments of the Mississippi lowlands. The or less pronounced and one in which the folds are is in the opposite direction. The general inclina­ The rivers of the Muscogee quadrangle, and exposed limit, however, is sharply marked here by not pronounced or are incidental to the faulting. tion of the strata is toward the south, and the fold­ especially the Arkansas, have developed in recent the western border of these flat-lying sediments, along Those of the first group occur in the central part ing of the rocks, except in one small area to be time relatively broad flood plains and second bot­ which the St. Louis, Iron Mountain and Southern of the folded and faulted district. Here, between considered later, is, locally, apparently due to the toms composed of silt, sand, and gravel. The Railway has been built. The eastern boundary Greenleaf and Fourteenmile creeks and included drag of the beds along the lines of faulting. Where rivers have deposited the sediment in their flood crosses Mississippi River near the mouth of the in their valleys, are three broad and shallow syn- these faults have an east-west bearing and the down­ plains to such depth that they now meander from Ohio and curves northward and then westward, clines whose northern limbs are wide and undulat­ throw is toward the north there is an interruption side to side in them, only occasionally touching the including a small district of southwestern Illinois. ing and nearly flat and whose southern limbs are of the southward dips and locally variable folding country rock at the sides and beneath the surficial The Ozark uplift has the form of an elongated broken and displaced downward toward the north is produced. Where the downthrow is in the deposits. dome whose axis trends approximately S. 70° W., by faults that extend generally parallel with and opposite direction there is simply an increase in The sediments deposited by Arkansas River con­ through the St. Francis Mountains in eastern Mis­ near the axes of the folds. The rocks on the down- the dip southward near the fault contact. sist of gravel, yellow sand, silts, and chocolate and souri, toward the northwest corner of Arkansas thrown side are strongly flexed upward toward the In the eastern part of the quadrangle there are red clays. The gravels are found along the river and the Muscogee quadrangle. The axis is not faults seemingly as a result of drag produced by three peculiarly sharp local upward folds. The banks near low-water line and in the lower part of marked by a definite crest, such as is usually the faulting. The axes of the anticlines lie near largest of these is near the mouth of Fourteenmile the older deposits, marking the beds of the river found in distinct smaller upward folds. For long at hand south of the main faults. Creek. Its axial trend is nearly north and south, during earlier stages. The sands are most abun­ distances across the axial part the strata are flat or The fault south of Greenleaf Creek ends east of in the direction of the general dip of the strata. dant near the present channel, while the finer silts but slightly undulating and are locally broken Garfield. As it dies out the slight folding with The fold is sharp and the dips are greater on the and chocolate clays have been deposited more abun­ by normal faults. As explained, the formations which it is associated increases and in the strike of east than on the west side. Of the two other local dantly toward the outer limit of the flood plain and incline at low angles from the northwest side of the fault there is a strong northward deflection in folds, one on Illinois River, in. the southeast corner in other localities protected from strong currents. the broad dome. Likewise, the strata pitch at a the rocks. This structure continues in the strike of T. 14 N., R. 21 E., is a small and sharp ellip­ The larger part of the Arkansas River deposits low angle along the axis toward the southwest. of the fault southwest to Arkansas River. tical dome, whose axis cuts across the trend of a was derived from the red strata of the Permian Between the axial part of the uplift and the Bos­ A second broad syncline and associated fault of larger faulted fold. The other, a small dome-like and the more friable Cretaceous, Tertiary, and later ton Mountains the structure is undulating and the this series occurs in and near the valley of Bayou uplift, lies 3 miles north of Melvin and within 2 surficial sediments of the western plains in Kansas rocks are locally faulted, resulting in a low slope Manard. This fault is also in the steep and nar­ miles of the northern border of the quadrangle. and Colorado, so that they necessarily differ from toward the south. In the southern slopes of the row southern limb of the fold and the rocks are Its axial trend is in the direction of the general the alluvium in the flood plains of the Verdigris Boston Mountains the tilting is increased by a suc­ steeply upturned on the northern or downthrown inclination of the strata. It is situated near one and the Neosho. cession of strong southward-dipping monoclines side. The northern limb of the syncline is broad fault and in the strike of another, but apparently Verdigris River drains the Carboniferous rocks accompanied by local faulting. and locally warped and is broken by three small is not related to either or to the warping of the of southeastern Kansas and northern Indian Ter­ faults that trend parallel with the larger structures. strata produced by them. ritory. Its alluvium, especially that of the finer PRAIRIE PLAINS MONOCLINE. Their downward displacements are toward the north, Relations of folding and faulting. As has silts deposited near the borders of the flood plain, The Prairie Plains constitute a broad and long as in the larger folds, but the local folding or warp­ already been explained, all the broader folds of is scarcely to be distinguished from the residual physiographic province that includes rocks of ing of the associated strata is apparently due to the Ozark uplift are related to the faults, but and local transported soils. varied geologic and structural character. In that the faulting. These local faults belong properly the general causes producing them can not be Neosho River receives a large part of its sedi­ part of the province, however, in northern Indian with the second class, in which the folding seems determined at the present time. That the fold­ ment from the cherty strata of the lower Carbon­ Territory, Kansas, and Oklahoma the structure is to be incidental to the faulting. ing in some instances has been accentuated by iferous in southeastern Kansas and southwestern generally monoclinal. West of the Ozark uplift The third large fold of this series of faulted folds the faulting is evident, and that they occurred Missouri. The silts, however, which are more the rocks are inclined at slightly variable but low is in the valley of Double Spring Creek. The about the same time is probable. An example of limy than those of Arkansas and Verdigris rivers, angles. ' Toward the south, in the plains near the southern limb is narrow and faulted, as in the the close relation and interdependence of the fold­ resemble closely the local transported soils of the eastern boundary, the westward pitch of the strata folds of Greenleaf Creek and Bayou Manard. ing and the faulting may be noted in the faulted Carboniferous shales in northern Indian Territory. increases from about 20 feet per mile in eastern The rocks are strongly flexed upward against the basin southeast of Crittenden, near the northeast STRUCTURE. Kansas to nearly 100 feet per mile at the south­ fault on the north as the result of the drag. corner of the quadrangle. In this instance the western limit of the Ozark region, near Muscogee. To the second series belong several smaller folds. basin is apparently bisected by the fault. If fold­ REGIONAL FEATURES. Toward the west, in the Prairie Plains, there is, on A very shallow syncline bears northeastward from ing had preceded the faulting or had been inde­ GENERAL STATEMENT. the contrary, a gradual decrease in the inclination Arkansas River Valley at the mouths of Greenleaf pendent of it evidence of folding of the rocks Sedimentary rocks of broad extent, consisting of of the strata. Locally there is a slight warping, and Cedar creeks. Near the boundary of the quad­ should appear on both sides of the fault, but the fine sand, clay, and lime, like those exposed in the but it is not known to be sufficient at any place to rangle this fold is broken by three faults which rocks are essentially flat on the southeast side of Muscogee quadrangle, were originally almost flat, reverse the westward dip of the rocks. trend northeastward into the Tahlequah quadran­ the fault, opposite the greatest displacement and though not necessarily horizontal, being doubtless The greatest variation in structure is found near gle. The rocks between the two southernmost the deepest part of the trough. The stresses pro­ slightly inclined with the sea bottom on which the western border of the Ozark uplift. Undula­ faults have dropped down with respect to the ducing the fold were evidently relieved on the they were deposited, in a manner similar to the tions in this uplift extend westward and die out in strata on the north and south, and a third fault southeast side of the fault by the fracturing of sediments being laid down off the shores of the the Prairie Plains monocline. crosses the quadrangle boundary a mile north of the strata. Similar phenomena of structure will continent at the present time. the downthrown block. It is the west end of a be found in the eastward extension of the faults STRUCTURE OF THE MUSCOGEE QUADRANGLE. After the Carboniferous period the region was fracture that extends 12 to 15 miles into the Tah­ and folds in the Tahlequah quadrangle and are uplifted and the flat strata were tilted, warped into Divisions. The Muscogee quadrangle is divided lequah quadrangle. In this instance the down­ illustrated in the Tahlequah folio (No. 122) by a folds, and broken by faults, as they are now found. structurally into two nearly equal parts by the Ozark throw is toward the north, resulting in a narrow, view of a model showing the deformed surface of It is not to be assumed that this tilting, folding, uplift and the Prairie Plains monocline. Arkan­ elevated, westward-pitching fault block near the the Boone formation. Muscogee, 6

Geologic distribution of faulting. The faults in submergence is found in the Chattanooga black and the occurrence of later rocks on its eastern bor­ wells drilled near its center proved to be barren, the Muscogee quadrangle affect only the Missis- shale, which was deposited over a very broad der show that the surface has oscillated and that the and a few wells drilled near the border of the town sippian and the lower part of the Pennsylvanian extent of country on the south and east sides of rocks have been locally deformed, but these are site, on the north, east, south, and west sides, did rocks. Both the faulting and the folding decrease the Ozark uplift, and in the other middle to late records of physiographic and structural history, riot yield oil in paying quantity. Other unprofit­ westward, and the former is not known to occur Devonian deposits lying on the northern flanks of and are described elsewhere. able wells have been drilled a few miles southwest west of Arkansas and Neosho rivers. The anti­ the uplift. These Devonian rocks are such as of Muscogee, at Fort Gibson, and at Wagoner, clinal folds pitch toward the southwest and, with would be formed in broad, shallow seas. MINERAL RESOURCES. each to a depth reaching or passing beneath the the synclines, grow gradually flatter and more That the land had been nearly base-leveled is geologic horizon of the oil-bearing sand of the indistinct until they are lost in the undulating shown by the fact that the Devonian sediments The Muscogee quadrangle contains coal, oil, Muscogee field. monoclinal structure of the Prairie Plains region, rest on the eroded surfaces and slightly beveled gas, building stone, limestone, road material, and The discovery of oil at Muscogee was made in in the western half of the quadrangle. The local edges of many older formations, ranging in age clay. To these resources may be added water, 1894, when two wells were drilled. In one of these variations in structure west of Arkansas and from early Ordovician to middle Silurian and con­ soil, and the forests, which deserve careful atten­ a sand was encountered at 665 feet which yielded Neosho rivers are not expressed in the mapping sisting of sandstones, shales, limestones, and dolo­ tion. The ores of zinc and lead may possibly 12 barrels of oil a day. Another sand, penetrated of the Winslow formation. Could certain sand­ mites; and that the submergence was comparatively be found in small quantities in the Boone for­ at 1100 feet, produced 60 barrels of oil a day. stone beds near the middle of the formation be rapid is indicated by the fact that the remaining mation, particularly near lines of faulting, as Active drilling for oil began in February, 1904, mapped their outcrops would mark wavy lines in minor hollows and channels were filled with this formation yields the lead and zinc ores of and during the year more than 30 productive wells a north-south direction near Muscogee, showing quickly accumulated land wash, consisting largely southwestern Missouri and of parts of northern had been drilled. Their combined capacity was the westward dying away of the folds of the Ozark of rounded quartz grains, before the more evenly Arkansas. The structural conditions in all these estimated at 1000 barrels a day. uplift. When the succeeding Boggy formation is spread shales and shaly limestones were laid areas are very similar; that is, the rocks are essen­ The Muscogee oil is greenish in color, turning reached, however, little effect of folding can be down. These initial deposits of this Devonian tially horizontal and are broken by normal faults. to a reddish hue in transmitted light. It is of discerned, the irregularities of the contact at the submergence make up the unequally distributed However, no zinc ores are known to occur in com­ much higher grade than any other oil produced in base of the formation being due to the surface con­ Sylamore sandstone, the local member of the mercial quantity in the Muscogee quadrangle. Indian Territory, having a specific gravity of 42° figuration of the land. Local variations of the dip Chattanooga formation, a full description of which Baume. The Muscogee oil has a paraffine base, COAL. of the rock occur, but as a whole the inclination of can be found in the Fayetteville folio. The gen­ while the residuum from the other oils in Indian the strata is toward the west at approximately 100 eral evenness of the old land surface and the rapid­ Bituminous coal of good quality occurs in the Territory is a bitumen or so-called asphaltum. feet per mile. ity of the submergence are further indicated by the Muscogee quadrangle, but has not been found in The oil-bearing rock at Muscogee is a fine-tex- total absence of any but the finest of clastic mate­ beds of sufficient thickness to be profitably mined tured, moderately hard, gray sandstone 12 to 18 HISTORICAL GEOLOGY. rial in the overlapping Devonian beds that lie except for local consumption. Coal has been pros­ feet thick. The texture of the rock is too fine to upon the Sylamore sandstone, although several pected and mined by stripping to a small extent at permit a rapid flow of oil through it, and in order The rocks of the Muscogee quadrangle were of the exposed older formations, as for instance the eight localities. The locations of these prospects to obtain a larger volume the sand is shattered by deposited in water as sediments from the waste of Tyner shale and the Burgen sandstone of the Tah­ are shown on the map by the usual conventional high-power explosives, a larger surface being thus neighboring lands and from the remains of ani­ lequah quadrangle, are friable rocks. Recogniz­ signs. gained for the passage of the oil. The oil-bearing mals and plants which lived in or near the borders able debris from the latter occurs only in the A coal bed has been mined by a single open­ sand was encountered at depths ranging from a of the seas when the sediments were being laid initial deposit, that is, in the Sylamore sandstone. ing in the eastern part of sec. 2, T. 17 N., R. little more than 1000 feet in the north end to down. These rocks are limestones, shales, and After the deposition of the Chattanooga shale 20 E. The mining or stripping is in the flat val­ about 1100 feet in the south end of the field, the sandstones, and when they were deposited con­ submergence of the region continued well into ley of Fourteenmile Creek 3 miles north of the difference in the depth being due chiefly to the sisted of limy ooze, mud, and sand, respectively. Mississippian time until the Boone limestone and St. Louis and San Francisco Railroad. The coal general southward inclination of the strata. The The character of these rocks when traced and chert were formed. The broad extent of this sub­ occurs in a black shale, 30 feet or more in thick­ surface of the land is generally undulating and a studied over a wide field tells the story, though not mergence is shown by the fact that patches of the ness, that lies above the thick limestone of the little lower in altitude at the south than at the the complete story, of the manner of their forma­ Boone formation occur almost up to the crest of Morrow formation and beneath certain sandstone north end of the field. tion. As successive formations were deposited the the Ozark dome. In later Mississippian time the beds of the Winslow formation. The coal is pre­ The wells at Muscogee were put down by several forms of animal and vegetable life changed or sea bottom was elevated and a part, at least, of the sumed to be in the Winslow formation and is the drilling companies and the same oil-bearing sand migrated and were succeeded by other forms. At Ozark region became land. Oscillations of land lowest known to occur in Indian Territory. The was penetrated by each. The succession of shale, certain stages in the sedimentation gaps in the life and sea, however, occurred until the completion of rocks in the immediate vicinity are approximately sandstone, and limestone was not interpreted alike record, accompanied by discordance in the char­ the Mississippian series, as is shown by the pres­ flat and the cpal lies near the surface, so that it by each driller. The logs of the wells, however, acter and structure of the rocks, show oscillations ence of locally variable formations of sand, clay, can be mined by stripping off the surface rock. accord generally in showing that shales and sand­ of the land and sea. The variations in the coarse­ and limestone. The bed is 22 inches thick and contains no shale stones, with thinner strata of limestone, make the ness, composition, and thickness of the formations In mid-Carboniferous time the sea withdrew, or other apparent impurities. The coal has been rock section from the surface down to about 700 give evidence as to the depth of the water in which leaving the Ozark region as land beyond the mined only at intervals and for local consumption, feet. At this depth thick limestones were gener­ they were deposited and the nature of the contigu­ boundary marked by the exposed top of the Mis­ and no analyses or tests of it have been made. ally encountered and there was greater resistance ous lands. The fossil remains not only show the sissippian sediments. The existence of a broad Several thin coal beds have been located and to the drill. Limestone, shale, and sandstone relative ages of the successive strata, but aid in land at this time is shown by the erosion of the prospected in the northwestern part of the quad­ in alternating succession continue, according to identifying and correlating formations which come highest Mississippian formations where the Penn­ rangle, south and west of Wagoner; also in the reports, down to the oil-bearing sand. On com­ to the surface in separated localities. sylvanian rocks come into contact with them. In southwestern part, 4 and 7 miles south of Mus­ paring this general record with the section deter­ Stratigraphically below the lowest rocks at the the south and southwest sides of the uplift, not­ cogee. These beds occur in the shale near the mined by detailed geologic mapping east of Neosho surface in the Muscogee quadrangle lie dolomites, ably in the Muscogee quadrangle, the uncon­ central and upper parts of the Winslow formation River, it is found that the top of the limestone occurs limestones, sandstones, cherts, shales, etc., of Ordo­ formity is not great, but farther up, toward the and in all cases lie approximately flat. The coal is 100 to 200 feet above the top of the Mississippian vician, Silurian, and Devonian age. These depos­ crest of the dome, higher rocks of the Pennsyl­ bituminous, but so far as known the beds are too series. In this region the thickness of the Missis­ its, with rocks of Cambrian age, appear around vanian series rest upon successively lower beds of thin to be mined with profit. A coal bed has been sippian is found to range from 200 to 300 feet. the older igneous rocks of the axial part of the the Mississippian. In southwestern Missouri, on prospected and mined by stripping near the south­ According to this interpretation of the well records Ozark uplift in southeastern Missouri. They the western slope of the uplift, the Boone forma­ west corner of sec. 7 and in the northeast corner of the Muscogee oil sand is interbedded with or lies make large areas in southern Missouri and tion shows evidence of mid-Carboniferous erosion, sec. 18, T. 12 N., R. 19 E. This bed is near the immediately beneath the Mississippian strata. northern Arkansas, and occur in several small and the depressions in its surface contain remnants top of the Winslow formation, in the horizon of A well recently drilled to a depth of 1167 feet tracts in the adjoining Tahlequah quadrangle. of Pennsylvanian conglomerates and shales. In the coal mined at Starvilla and at Stigier, in the at Fort Gibson furnished 65 samples of various They reveal a record of sedimentation which is central Missouri, on the northern slope of the adjoining Sansbois quadrangle. The coal beds at kinds of rock penetrated, from which a reasonably not essential to the geologic history of the Mus­ Ozarks, Coal Measure shales and coal occur in all these localities correspond Stratigraphically with accurate section of the rocks is obtained. From cogee quadrangle and deserves but brief mention. sinkhole-like depressions in what are probably the McAlester coal, in the southern part of the this material the fact is developed that the cherty That a large part of the region underwent numer­ Ordovician strata. Thus it is seen that after the Indian Territory coal field. The beds in the Boone formation of the Mississippian series that is ous oscillations of level above and below the sea elevation of the Ozark region in mid-Carboniferous Muscogee quadrangle are inclined 2° toward the exposed at the surface in eastern Cherokee Nation is recorded by the alternation of formations of time it was again submerged, but to what extent southwest. The coal is of good bituminous grade, is a dark-colored siliceous limestone where it reaches saccharoidal sandstone, dolomite, limestone, and is not known, since so large a part of the forma­ clean, and from 18 inches to 2 feet thick. A depths below the level of weathering. The Boone shale, and by the occurrence of conglomerate. tions of Pennsylvanian age has been removed from considerable quantity has been stripped near the formation makes a large part of the Mississippian Some of these formations have been deposited the uplift. The waters in which the Winslow and railroad in the NE. ^ sec. 18. The development series in the Cherokee Nation and is the only part unconformably upon others, showing intervals later formations of the Pennsylvanian series were near the southwest corner of sec. 7 is recent, and of the Mississippian known to the well driller. of erosion. deposited were shallow; the bottoms of the seas the output is used for local consumption. This cherty limestone was believed to be the After the deposition of the St. Clair marble, the frequently rose to the surface, and the lands were A coal bed is mined on Elk Creek 2 miles south horizon beneath which oil was not known to occur only Silurian formation in the southwestern part low, as is attested by the alternating and irregu­ of the point where the Creek-Cherokee line ap­ in the Indian Territory field. of the Ozark region, there was a break in the sedi­ larly bedded deposits of shale and sand. The proaches thd southern boundary of the quadrangle. mentary record, corresponding to the closing por­ lands extended beyond the confines of the Ozark Its outcrop, extended northwestward, should cross NATURAL GAS. tion of Silurian and to early Devonian time. In uplift. The Pennsylvanian sediments grow thicker the southwest corner of the quadrangle. It is a Beds of sandstone occur in the Muscogee oil field this long interval the rocks were folded into low and contain a greater quantity of coarse material good grade of bituminous coal 2 feet 6 inches thick, at depths of 800 to 840 feet which yield, locally, undulations and uplifted into land. Probably toward the south and east, indicating the direction and is being mined for local consumption. salt water and gas. They are referred to by the while the folding was in progress, and certainly of the land from which the great abundance of driller as "salt sands." Several of the wells have OIL. after it had occurred, the land was reduced by ero­ sand especially was derived. Additional evidence yielded considerable quantities of gas from this sion to a low and nearly level surface. This land of this is the fact that the later beds of the Penn­ The production of oil in the Muscogee quad­ horizon, but the supply not being large in most was submerged in late Devonian time. These sylvanian deposits which overlap the old rocks of rangle is limited to the immediate vicinity of cases, drilling was continued down to the oil sand. conditions prevailed not only in the vicinity of the Ozark dome decrease in thickness northward Muscogee. The productive territory at the time A gas flow was encountered at a depth of 825 feet the Muscogee quadrangle, as shown in the adjoin­ and contain little coarse sediment. of investigation, in July, 1904, was located in the in a well near the center of the west side of the oil- ing Tahlequah quadrangle and at many localities After the close of the Carboniferous the whole southeastern part of the town, on a strip of producing area. The capacity of this well was in Missouri and northern Arkansas, but seem to region was raised above the sea and there is no land one-fourth of a mile wide and a mile long, estimated to be 1,000,000 cubic feet a day. The have extended over nearly the whole of the mar­ record of sedimentation to indicate that it has since extending from northeast to southwest. This land gas was utilized as fuel for some time, but later it ginal part of the Ozark uplift. The record of this been submerged. The features of the Ozlirk region is not all oil bearing, however, for a group of six was ignored and drilling was continued to the oil rr

sand, where a profitable flow of oil was obtained. and Tahlequah. The Kansas City Southern Rail­ the western slope of the hill 7 miles southeast of do the limestone beds in the upper part, and with Another well, at the north end of the area, yielded road also approaches limestone outcrops south of Muscogee, on the Muscogee-Braggs road. the addition of wash from the overlying Pitkin an estimated flow of more than 1,000,000 cubic Fort Gibson and between Braggs and Campbell. A number of springs issue also from the base of and Morrow limestones a considerable part of the feet of gas daily, but it became flooded by a strong the terrace-sand deposits southwest of Braggs and Fayetteville formation produces good agricultural, flow of salt water and had to be abandoned. EOAD MATERIAL. between Arkansas and Verdigris rivers. These lands. Where the surface is flat, however, and is The various classes of rocks enumerated in the sands are not consolidated, and a large part of the underlain by shales of the central part of the for­ BUILDING STONE. discussion of building stone may be used as mate­ water that falls on them ultimately issues at points mation, the soil is not highly productive. Near the base of the Fayetteville formation there rial for road construction. Among those suitable where they are in contact with the impervious Car­ The Pitkin and Morrow formations produce the are certain beds of dense, evenly stratified limestone for this purpose are certain siliceous limestones of boniferous strata. most fertile soils in the region, but usually occur that may be utilized for building purposes. The the Morrow and Pitkin formations and the more Wells. It is practicable to obtain water in on steep slopes, where much of the rock is exposed. strata vary from a few inches to a foot or more in indurated and thinly.bedded sandstones found in wells at almost any place in the Muscogee quad­ The fertility of these soils is attested by the lux­ thickness. As a whole the section of these beds various parts of the Winslow formation. The rangle, but the flow and quality of the water uriance of the forest and the occurrence of walnut, varies from place to place, aggregating a maximum residual chert of the Boone formation, however, depend on the position of the well and the kind locust, and other trees that grow, naturally, on fer­ of about 15 feet. The fresh rock varies from dark in the northeastern part of the quadrangle, sur­ of rock penetrated. Abundance of water of good tile soils. to light blue, but on weathering it changes to drab passes all of these in quality as road metal. On quality may be obtained from the Boone formation The Winslow formation produces a varied soil. and yellowish blue. weathering the Boone formation has left a deep and from the thicker sandstone beds of the Wins- East of Arkansas and Neosho rivers a large part Deposits of limestone similar in color and hard­ and, for the most part, loose mantle of angu­ low and Boggy formations. Wells driven into the of the formation is too rugged and stony to be ness to the limestone of the Fayetteville formation lar chert that can be removed with comparative surficial sands of the terrace or river-bottom depos­ utilized for agricultural purposes. In more level occur in the Pitkin and Morrow formations. These ease. This chert when crushed produces a dur­ its yield an abundant supply of water. upland tracts, where there is a mixture of sand limestones vary from thin layers to beds nearly 2 able roadbed and with use becomes consolidated Water from the Boone cherty limestone con­ and clay, the result is a loamy soil well adapted to feet thick. There is also variation from bed to and cemented into a compact mass. Broad areas tains a considerable percentage of lime and is the growth of vegetables and fruits as well as of bed as to purity and hardness. Certain layers are oft the Boone chert occur in the northeastern commonly classed as "hard," while that from the cereals. In the western part of the quadrangle dense, fine textured, and crystalline; others are part of the quadrangle and are accessible to wide sandstone and surficial sand deposits may con­ soil of the same class is found on the westward- more earthy and shaly. All are more or less fos- tracts of country underlain by Coal Measure tain an appreciable amount of iron as a carbonate sloping hills and ridges. In this region relatively siliferous, and the fossils, particularly where abun­ shales and to river-bottom lands where good roads or sulphate. In many instances, however, it is wide tracts of sandstone approach the surface. The dant, will lower the quality of the stone. The will be in demand. This chert is also accessible by almost pure. shale in the upper part of the Winslow formation, quantity of this limestone is practically unlimited, railroad to Muscogee and Wagoner and should be Water in wells in the Winslow formation a few together with included thin limestone, sandstone, and its occurrence is shown on the geologic maps in demand for street improvements in these cities. hundred feet in depth, located in the immediate and limy strata, naturally has produced grassy, by the boundaries of the Pitkin and Morrow valleys of Double Spring and Fourteenmile creeks open uplands. Until recently these lands were CLAY. formations. arid of Bayou Manard, may rise nearly to the sur­ given over for the most part to native grasses and The Winslow formation contains many beds Clay shales occur in abundance in the Fayette­ face or may overflow, but the volume is not likely were utilized as grazing and meadow lands. Now, of sandstone, some of which is adapted to certain ville, Morrow, and Winslow formations. All of to be great nor the flow to be strong. The sand­ however, since the lands have been allotted to the uses in building construction. Large quantities them vary in their different parts in percentage of stone beds that contain circulating water are usu­ citizens, they are being rapidly opened to the cul­ of stone may be obtained for foundations, fencing, lime, sand, and iron. ally of fine texture and do not permit water to tivation of corn and cotton. and other ordinary farm improvements. Many The shales of the Morrow formation occur in flow freely through them. Water obtained in the The soils of the terrace sands and river-bottom sandstone beds are exposed or lie near the sur­ its middle and upper parts. Those in the middle shales is usually in weak flows and almost invari­ lands consist of loamy sands, loams, and silty face in the hills west of the Arkansas between lie between beds of limestone and probably con­ ably contains alkaline salts in solution. Deep clays. A very large part of the terrace sands and Muscogee and Webbers Falls, and on both sides tain a considerable percentage of lime. Those in wells sunk at Wagoner and Muscogee to depths much of the Arkansas River bottom lands within of the Neosho. The same beds occur at the sur­ the upper part are thicker, but are more variable of 1000 to 1800 feet in search of oil and gas show the flood plains contain deep, loamy sand of but face in the hills east of these rivers. Many of in proportion of lime and sand. There are beds that potable waters are probably not obtainable by moderate fertility. The larger part of the Arkan­ these beds are of workable dimensions, separated of even-textured shale, however, in this formation deep-well drilling in the Muscogee quadrangle. sas and Verdigris alluvium, however, consists of by thin layers of shale that permit more easy which may produce brick clay. Surface water. Four rivers, besides a number highly fertile silts and silty clays. The alluvial quarrying of the stone. Sandstone beds that pro­ More than half of the Winslow formation con­ of smaller streams, flow through the Muscogee deposits of the Neosho and the limited bottom duce building stone occur also above the middle of sists of shales. These occur chiefly in the upper quadrangle. Two of these, Arkansas and Verdi­ lands of the Illinois and of smaller streams in the the formation. Some of these outcrop in the part, though many beds are interstratified with the gris rivers, carry a relatively large amount of silt eastern part of the quadrangle contain a larger per­ escarpment west of Dirty Creek and at the heads sandstones in the lower part. They range from in suspension, and the Arkansas, especially during centage of limy material and are very fertile. of Spaniard, Sam, Coata, and Pecan creeks. Large very sandy deposits to purer shales which may be the summer season or at times of low water, con­ FORESTS. areas of the sandstone beds crop out or lie beneath utilized in the production of brick. The purer tains an appreciable amount of salts in solution. the soil on the gentle westward slopes of the hills. shales occur in the central and upper parts of the The waters of these rivers are not considered The forests of the Muscogee quadrangle consist A group of sandstone beds 30 to 40 feet thick formation, and they are believed to be almost free wholesome for drinking purposes during low entirely of the hard woods common to this latitude occurs in the vicinity of Muscogee and crops out from lime. stages or in the summer season. in the western part of the Mississippi Valley. from that point westward to the boundary of the The clay shales ,of the same formation are found With Neosho and Illinois rivers, however, the They include many species of oak and hickory, quadrangle. This stone caps local table-lands in in the vicinity of Van Buren, near the Arkansas- conditions are different. These streams are fed besides ash, walnut, cherry, locust, sycamore, and the center of sec. 23, T. 15 N., R. 18 E., and Indian Territory line, where some of them have by many springs from the Ozark region, their cottonwood. Many varieties of wild grape abound extends on the lower ridge to the Mission. They proved to be high-class brick clays. To be volume is more regular, and their waters are on both high and low lands. also cap the hill in sec. 20, T. 15 N., R. 18 E., utilized they require to be crushed or ground. usually clear. Many of the smaller streams east Originally all bottom lands were thickly forested and the table-land east of Pecan Creek. This rock They are moderately soft, however, and their of Arkansas and Neosho rivers are perennial, with large trees. Now almost this entire forest is occurs in both massive and thin beds, the thicker reduction may be accomplished with comparative being fed by springs. Those west of these rivers, destroyed in those parts where the land is-tillable. strata being usually in the central part of the sand­ ease. These shales disintegrate readily, forming however, which have their sources in the Carbon­ The areas of sandstone and limestone,*, ' which stone group. The unweathered rock is of gray ovr clay soils, and are not usually exposed. iferous shales, are intermittent in flow, and during include almost all the country east of Arkansas bluish tint and in certain beds has an even, fine dry seasons the water stagnates in pools. and Neosho rivers, contain a forest of variable texture and is moderately hard, furnishing free­ WATER RESOURCES. density and luxuriance. The part occupied by SOIL. stone of a fair quality. Certain beds in the lower The ground-water supply of the Muscogee quad­ the Morrow and Boone formations contains a part of this group cap the small table-land at the rangle is limited almost entirely to the area of the Except for tracts of bottom land of transported sparse forest of oak, hickory, walnut, locust, etc., northern edge of the city of Muscogee, and the rock Boone formation. The higher rocks, consisting soil distributed along the river valleys, the soils especially on the northern slopes of hills. On is quarried and used successfully in large building chiefly of sandstone and shales, are practically of the Muscogee quadrangle are formed in place southward-facing slopes the trees are less abun­ construction. In 1902 massive beds about 8 feet impervious to water and afford only a few springs by the weathering of the rocks beneath them. dant and smaller, and here much open land is thick near the middle of the exposure were being of weak flow. The river deposits are mapped as river alluvium found. The Winslow formation bears a forest quarried. On weathering stratification planes Springs. The Boone formation, although orig­ and terrace sands and are treated as formations. consisting chiefly of oak and hickory of only develop, separating the beds into dimension inally an impervious deposit of limestone and In view of the fact that the soils, with these excep­ moderate size except on the northern slopes, where layers, and these planes are utilized in quarry­ chert, is permeated with underground solution tions, are residual, the geologic map may be con­ the trees attain larger growth. On southern ing the stone. The weathered stone assumes, channels both across and along the bedding of sidered as a soil map also. slopes of hills and on tracts of shaly soil the forest durable shades of yellow and brown. the rocks. Many of these underground channels The Boone formation produces a cherty soil. is more open, being interspersed with small areas Large areas of sandstone are exposed in the come to the surface in the valleys and their waters On weathering the chert breaks into angular of prairie land. 'table-land of the Rattlesnake Mountains and in the issue as springs. Others rise, the water issuing blocks and fragments and, because of its great The western slopes of the hills lying along the hilly district east of Oktaha. Some of the beds from joint fissures or faults in the rocks. A num­ durability, forms a surface layer. The soil it pro­ east sides of Arkansas and Neosho rivers are occur in layers suitable for quarrying and doubt­ ber of large springs issue from the fault that duces is fertile, but is carried downward and away forested, while the opposite sides are covered by less will be utilized as agriculture develops in the extends down Double Spring Creek from the by the rains, or where left in place is mixed with growths of stunted trees and thorny shrubs inter­ contiguous districts of fertile laud. northeast corner of the quadrangle. Others issue a residuum of weathered chert. Thus over a large spersed with patches of prairie. from the fault near the sources of Greenleaf part of the Boone formation, especially in the The western half of the quadrangle is almost LIMESTONE. Creek and Bayou Manard. A group of saline more hilly districts, the soil is too thin, or at too treeless except along the immediate valleys of Certain beds of limestone in the formations springs of small flow issue from the limestone great a depth beneath the weathered material, or the streams and within a few limited areas of referred to as containing building stone may be and chert formations in the southeast corner of T. too stony, to be of value for agricultural purposes. thick sandstone outcrops. A small forest tract utilized in the manufacture of lime. These lime­ 14 N:, R. 21 E. The rocks here are steeply The soil under these conditions can be of service of stunted oaks occurs on the sandstone highland stones occur near the base of the Fayetteville and upturned and the waters appear to come up only to the forest, which seemingly thrives in accu­ bordering Pecan Creek on the east. The table­ in the Pitkin and Morrow formations. The beds through the bedding planes of the chert and mulations of loose stone. In certain localities land of the Rattlesnake Mountains bears a simi­ differ in purity or in percentage of carbonate of limestone of the Boone and JMorrow formations. where the surface has remained flat for a long lar forest. Small tracts of oak forest also occur lime. Some of them, however, may produce a Springs of small flow issue from the thicker time the soil is sufficiently thick to be cultivated, on the sandstone divides east of Butler Creek. commercially valuable lime. sandstone beds of the Winslow formation at fav­ as in the fertile lands about Crittenden and in Scattering trees are found on the prairie uplands, A branch of the St. Louis and San Francisco orable situations, where the beds are considerably other smaller tracts in the northeastern part of the and forest trees transplanted into the same areas Railroad has recently been built across the quad­ tilted and where erosion has cut deeply into them quadrangle. have prospered, showing that it is feasible to rangle and is conveniently situated for the devel­ across the strike of the rocks. One of the most The limestone near the base of the Fayetteville extend the forest. opment of lime industries between Fort Gibson noted of these springs flows from the sandstone in formation assists in giving fertility to its soil, as May, 1905. Muscogee.