The Stratigraphy and Structural Development of the Salina Basin of Kansas
by Wallace Lee, Constance Leatherock, and Theodore Botinelly
Originally published in 1948 as Kansas Geological Survey Bulletin 74. This is, in general, the original text as published in 1948. The information has not been updated.
Abstract
This report describes the stratigraphy and structural history of the Salina basin in Kansas and adjoining areas. The stratigraphic descriptions are based on a microscopic examination of samples from wells.
The rocks of the basin range in age from Pre-Cambrian to Quaternary but many hiatuses make the record incomplete.
Stratigraphy
The Pre-Cambrian rocks consist of red granite or granitic gneiss.
The Upper Cambrian Series is represented by the Lamotte sandstone, Bonneterre dolomite, and Eminence dolomite. The Lamotte sandstone is absent in most parts of the Salina basin but at one point it reaches a thickness of 80 feet. The Lamotte grades upward into the noncherty glauconitic Bonneterre dolomite, which has a thickness of more than 180 feet at some places. The cherty Eminence dolomite is bounded at the base and top by unconformities. It has been recognized only in McPherson County where it has a thickness of 35 feet.
The Lower Ordovician Series is represented in central Kansas by the Van Buren formation, Gasconade, Roubidoux, Jefferson City, and Cotter dolomites, and St. Peter sandstone. The Van Buren dolomite is cherty and at the base contains the Gunter sandstone member. The Van Buren and overlying Gasconade dolomite, which are inseparable in this area, have a thickness of 50 feet in southern McPherson County; strata of this combined unit thicken southward but disappear northward. The Roubidoux dolomite is widely distributed in Kansas but is absent on the crest of the Southeast Nebraska arch and parts of the Central Kansas uplift. The dolomite rests unconformably on rocks ranging from Pre-Cambrian granite to the Gasconade dolomite. In the Salina basin the Roubidoux comprises sand~, dolomite having a maximum thickness of 247 feet; it lacks sandstone zones such as characterize this formation in Missouri. The undivided Jefferson City-Cotter sequence, which overlies the Roubidoux, is commonly present. Its maximum known thickness is 410 feet in Rice County. The St. Peter sandstone, 10 to 90 feet thick, rests unconformably on all the older rocks. It is divisible into three members.
The Middle and Upper Ordovician rocks of the Salina basin consist of the Platteville formation, Kimmswick dolomite, and Maquoketa shale, each bounded by obscure disconformities. The Platteville and St. Peter beds are equivalent to part of the Simpson group of Oklahoma, the Kimmswick corresponds to part of the Viola limestone of Oklahoma, and the Maquoketa equals the Sylvan shale of Oklahoma. The Platteville consists of shale, sandy clay, sand, and dolomite; a persistent dolomite at the base is a reliable datum bed. The Platteville thickens toward northeastern Kansas, ranging from a featheredge in McPherson and Marion Counties to 60 feet in Pottawatomie County. The Kimmswick dolomite consists of alternating beds of cherty and noncherty dolomite and some limestone in which three zones are recognizable. It thickens toward the northeast from 20 feet in Harvey County to 310 feet in Washington County. The Maquoketa shale consists of gray silty dolomitic shale and locally very cherty dolomite at the top. Insoluble residues of the shale reveal conspicuous dolomolds. The thickness of the Maquoketa, except in parts of Osborne and Smith Counties where it is absent, ranges irregularly from 40 to 155 feet. The variations in thickness are due mainly to pre-Silurian erosion.
The Silurian rocks consist mainly of coarsely sucrose and granular dolomite which is divisible into five zones, of which the lower three are correlated with the Chimneyhill limestone of Oklahoma. The Silurian increases in thickness toward the northeast from 117 feet in Dickinson County to 270 feet in Marshall County.
The Devonian rocks contain two recognizable zones and consist mainly of dolomite but limestone is present in the southwestern part of the area where the Devonian is thin. Sparsely distributed sand occurs in the lower part of the sequence and sandy dolomite commonly marks the base. Thickness of these rocks is variable, owing to pre-Chattanooga erosion, but it increases irregularly northeastward from a featheredge in the southern part of the area to 215 feet in Nemaha County. An important unconformity, comparable to that at the base of the St. Peter sandstone, separates the Devonian rocks from older formations.
Between the Devonian dolomites and Mississippian limestones, sandstone and shale of uncertain age comprise the Misener sandstone, Chattanooga shale, and Boice shale. They are separated from older rocks by an angular unconformity that extends over a broad region. The Misener is a discontinuous unit composed of sandstone or sandy shale. The Chattanooga consists mainly of gray finely micaceous shale containing sparely distributed spores but dark shale, in its lower part, bears many spores. Impure silty or clayey dolomite and limestone occur locally in the middle part of the Chattanooga.
The shale thickens irregularly northeastward from 100 to more than 200 feet, but pre-Chattanooga valleys in McPherson County contain as much as 250 feet of beds belonging to this formation. The Boice shale, which overlies the Chattanooga unconformably, occurs in the northeastern part of the Salina basin area. The basal deposits are red and generally are characterized by ferruginous oolites, but the upper part resembles the Chattanooga.
The Mississippian limestones of the Salina basin consist of many units: an upper member of the Sedalia dolomite and the Gilmore City limestone, of Kinderhookian age; the St. Joe, Reeds Spring, Burlington, and Keokuk limestones, of Osagian age; and the "Warsaw" and Spergen limestones of Meramecian age. The Mississippian limestones in central Kansas are now confined to synclinal areas but originally they were more widespread. The upper formations probably extended northward beyond the Salina basin and westward across the Central Kansas uplift.
The Kinderhookian rocks in the Salina basin belong to the upper part of the series. They occur principally in the northern two-thirds of the area, but outliers occur as far south as Sedgwick County. The upper member of the Sedalia dolomite is a brownish noncherty sucrose dolomite, rarely more than 15 feet thick, that lies disconformably on the Chattanooga shale. The Gilmore City limestone, unconformably above the Sedalia, consists of soft noncherty granular limestone containing some oolitic zones. The thickness of the Gilmore City increases toward the north and reaches it maximum of 62 feet in Mitchell County.
The St. Joe, Reeds Spring, and Burlington limestones overlap northward upon a beveled surface of Kinderhookian rocks. The St. Joe limestone is noncherty or slightly cherty argillaceous dark-gray limestone which is 40 feet thick in Harvey County. It is overlain conformably by the Reeds Spring limestone, characterized by abundant semitranslucent bluish-gray to gray chert. This unit is 100 feet thick in Harvey County and overlaps beyond the St. Joe to the east, west, and north, where a tongue extends into Ottawa County. The Reeds Spring limestone is conformably overlain by the undifferentiated Burlington and Keokuk limestones, which comprise two zones separated by an unconformity. The lower zone, partly or wholly of Burlington age, is characterized by white blocky opaque chert; the upper zone, partly or wholly of Keokuk age, is characterized by rough, pitted, and porous chert and includes siliceous material resembling tripoli. The Burlington-Keokuk sequence is 170 feet thick in Harvey County but it thins irregularly northward to 100 feet in Republic County.
The "Warsaw" limestone consists mainly of limestone containing much microfossiliferous chert. Its thickness varies greatly on account of the relief of the pre-"Warsaw" erosion surface; the limestone is 95 feet thick in Harvey County and 35 feet thick in Ottawa County. The Spergen limestone, which succeeds the Warsaw limestone with seeming conformity, consists mainly of noncherty, or sparsely cherty granular limestone. The small amounts of chert generally include semitranslucent salmon-colored or pink chalcedony or small amounts of microfossiliferous chert like that in the Warsaw.
The thickness of the Mississippian rocks as a whole is related in large measure to structural features. In the deepest part of the Salina basin these rocks are 350 feet thick, but on the margin of the basin, as well as on the crests of local anticlines, the youngest Mississippian formations were removed by pre-Pennsylvanian erosion.
The rocks of Pennsylvanian and Permian age consist of numerous alternating sequences of limestones, marine and nonmarine shales, and sandstone. Each sequence was deposited during a cycle that included an advance and retreat of the sea.
The Cherokee shale, of Desmoinesian age, consists mainly of alternating shale and sandstone interstratified with coal and thin limestones. The Cherokee is about 300 feet thick in the center of the Salina basin but is absent through nondeposition on the Central Kansas uplift and the northern end of the Nemaha anticline. The Marmaton group, the next higher unit, consists of alternating limestone and shale which are not sharply differentiated in the subsurface. The group is probably about 100 feet thick in the Salina basin.
Missourian rocks, comprising the lower part of the Upper Pennsylvanian Series, are separated from Desmoinesian formations by an unconformity that is marked by channeling and a faunal change. Of Missourian age are the Pleasanton, Kansas City, Lansing, and Pedee groups. The Pleasanton group is not clearly distinguishable in the log,s of all wells; its thickness seems to be less than ?5 feet at most places. The Kansas City and Lansing groups have an average aggregate thickness of about 350 feet in the Salina basin, and consist dominantly of limestone with alternating beds of shale, which clearly reveal the cyclical deposition of the rocks. The Pedee group is probably not represented in the Salina basin area.
Virgilian rocks, which comprise the upper part of the Upper Pennsylvanian Series, include the Douglas, Shawnee, and Wabaunsee groups. An important unconformity separates the Virgilian from underlying beds. The Douglas group consists largely of shale and sandstone with one or more thin interbedded limestones. In the central part of the Salina basin, it is about 175 feet thick but it is thinner toward the margins of the basin. The Shawnee group consists of four formations of limestone that alternate with three formations of shale. The thickness of the group is 360 feet in the center of the Salina basin. The Wabaunsee group, which consists dominantly of shale interbedded with many relatively thin limestones, ranges in thickness from 200 to 400 feet, owing to an unconformity at its top.
The Wolfcampian Series, of Early Permian age, rests on an uneven surface of Pennsylvanian rocks in which deep channels were cut and subsequently filled with sand. The relations of the beds adjacent to the unconformity indicate regional tilting of the beds below it prior to the beginning of Permian sedimentation. Three groups called Admire, Council Grove, and Chase, are recognized in the Wolfcampian Series. The Admire group consists of shale and sandstone interstratified with thin limestones and ranges in thickness from 100 to 250 feet. The Council Grove group attains a thickness of 375 feet in the Salina basin and consists of well-developed limestones, in part argillaceous, interstratified with shales which become increasingly red and variegated toward the top. The Chase group ranges in thickness from 340 to 375 feet and is similar lithologically to the upper part of the Council Grove group but it includes two persistently cherty limestones, the Wreford and the Barneston, both of which are useful datum beds in subsurface stratigraphy.
The Sumner and Nippewalla constitute the Leonardian Series. The Sumner group is composed of the Ninnescah shale, which is mostly red, the Stone Corral dolomite, which includes some gypsum, and the Wellington formation which consists mainly of gray shale and gypsum and includes the Hutchinson salt member. The Sumner group has a thickness of 500 to 750 feet. The only part of the Nippewalla group present in the Salina basin is red shale which lies at the base of the group. Higher Permian rocks were eroded prior to Cretaceous time.
The rocks of Cretaceous age have an aggregate thickness of more than 1,000 feet on the western border of the Salina basin area and include the Cheyenne sandstone and Kiowa shale of the Comanchean Series, and the Dakota formation, Graneros shale, Greenhorn limestone, Carlile shale, and Niobrara chalk of the Gulfian Series.
The Tertiary and Quaternary Systems are represented by alluvial deposits in ancient valleys and on high level benches. In the northeastern part of the area, glacial till and loess occur in upland areas. These deposits are more than 150 feet thick at some places and in large areas conceal the underlying consolidated rocks of Cretaceous, Permian, and earlier age.
Structural development
Study of the structural development of the Salina basin and adjacent areas has been approached by preparation of thickness maps and stratigraphic cross sections. The interpretation of structural movements from thickness maps is based on the concept that if a sequence of rocks is deposited on a flat surface and then warped before a younger horizontal surface is developed, variations in the thickness of the rocks between the two surfaces reveal the amount and place of the deformation.
Five periods of folding are distinguished.
(1) Upper Cambrian and Lower Ordovician dolomites lying below the St. Peter sandstone were deformed before the deposition of the St. Peter sandstone. The structural movement revealed by the thickness map of this sequence (Pl. 1) resulted from many minor movements that occurred at different times prior to the deposition of the St. Peter sandstone. The movements involved a subsidence of a deep basin in central Missouri in which more than 2,000 feet of dolomites are preserved. During the same epoch, a south-trending positive area, termed the Southeast Nebraska arch, was developed in southeastern Nebraska and northeastern Kansas. On the crest of this arch, the St. Peter rests on Pre-Cambrian granite and on the flanks it rests on the beveled edges of the Late Cambrian and Early Ordovician formations. In central Kansas, a parallel syncline is revealed by the thickness map.
(2) Another period of folding extended from St. Peter time to the beginning of deposition of the Mississippian limestone and may have continued through Kinderhookian time. During this period the structural deformation was a complete reversal of that preceding St. Peter time, for now the Ozark uplift rose from the deepest part of the previously subsiding area in southern Missouri and the previously rising Southeast Nebraska arch became the site of the gradually subsiding North Kansas basin, Events that were contemporaneous with the subsidence of the North Kansas basin and the rise of the Ozarks were the development of the Chautauqua arch and the Central Kansas uplift on the south and west. Although the development of these features was more or less continuous and occurred during periods of sedimentation, a considerable part of the folding took place during the hiatuses preceding the deposition of the Devonian rocks and preceding the deposition of the Chattanooga shale. The unconformities that are expressions of these hiatuses show beveling of previously deposited formations and thus show the development of structural elements. The subsidence of the North Kansas basin by the end of Chattanooga time (Pl. 7) was not less than 1,200 feet and may have been several hundred feet greater.
(3) A third period of folding began at least as early as the beginning of Mississippian time, culminated after Mississippian deposition, and continued with diminished movement through Pennsylvanian into Permian time. The principal structural feature developed in Kansas was the Nemaha anticline, trending slightly east of north, which was flanked by the Salina basin on the west and the Forest City basin on the east. The Salina basin was a synclinal area which trended northwest and paralleled the northern flank of the Central Kansas uplift. Secondary anticlines, paralleling both the Nemaha anticline and the Salina basin syncline were also developed. The Central Kansas uplift, which had been a positive area since St. Peter time, continued to develop; the Chautauqua arch remained quiescent at the end of Mississippian time although parallel minor anticlinal movements continued along its trend into Pennsylvanian time. It was later crossed at right angles by the Cherokee synclinal basin; a rising surface in southeastern Nebraska cut eastward across the deepest part of the North Kansas basin.
The pre-Pennsylvanian movement of the Nemaha anticline were distinctly anticlinal with steeper dips on its east side than on the west. Early Pennsylvanian movements steepened the east dip, and in many places developed a structural escarpment. At the same time, the region to the west was raised, with only minor anticlinal movements on the crest of the anticline. The west limb became essentially a monoclinal slope broken by a series of secondary folds paralleling the escarpment. The gradual elevation of the western area did not permit the Pennsylvanian sea to inundate the Salina basin until long after it spread over the Forest City and Cherokee basins. Appreciable deformation of the Central Kansas uplift and the Salina basin, as recorded by 50-foot thickness lines, ceased after Wolfcampian time or a little earlier. This is shown by the formation of the Hutchinson salt basin across the end of the Central Kansas uplift in mid-Permian time. The continued growth of many local and secondary anticlines paralleling both the Nemaha anticline and the Central Kansas uplift is, however, recorded in rocks even younger than the Wolfcampian.
During the cyclical deposition of most of the Pennsylvanian and Early Permian rocks, the floor of the Salina basin area stood close to sea level. The limestone beds have a relatively even thickness but the shales thicken with considerable regularity southeastward toward the Ouachita basin. Eastern Kansas lay on the margin of a much larger structural feature centering in the Ouachita basin in which Pennsylvanian rocks older than Marmaton accumulated to a thickness of 18,000 to 20,000 feet. Compared to the deformation of the Ouachita basin, the structural features developed in Kansas, although important, are insignificant.
(4) A fourth period of deformation occurred after Permian time and before Cretaceous time. It involved the development of a broad synclinal basin in southwestern Kansas which gave the Permian and Pennsylvanian rocks of eastern Kansas a southwesterly dip.
(5) A fifth period of deformation occurred after the deposition of the Cretaceous rocks. As a result of this deformation these rocks were tilted toward the northeast in western Kansas and toward the north and northwest in central Kansas and were raised 1,500 to 2,000 feet above sea level in the Salina basin.
Each change in the pattern of structural movement altered the attitude of earlier anticlines as well as earlier regional structure. Changes in the direction of dip shifted the position of the crests of low anticlines in some cases and destroyed the closure in others. In consequence, the exposed crests of low anticlines in the younger rocks do not, in all cases, reveal accurately the position and configuration of those anticlines in older more steeply dipping rocks.
The repeated changes in the pattern of deformation and the repeated re-elevation and beveling of the formations influenced the migration and distribution of fluids in the rocks. Each structural movement, particularly those involving changes of dip, caused readjustments in the distribution of connate waters. The movements of nascent gas and oil were affected, and in some cases, earlier accumulations of oil and gas were probably lost.
The maps show the areas in which well-known zones of production will not be found owing to erosion or to nondeposition. The areas in which potentially productive zones wedge out beneath beveled surfaces are at least theoretically favorable to the development of stratigraphic traps.
Available data from the thickness maps of this report suggest that anticlinal conditions are present in northern Lincoln County. Also. northeasterly and northwesterly trending folds are probably concealed by or only weakly revealed in the Cretaceous and Upper Permian rocks in the central and northern parts of the Salina basin.
Kansas Geological Survey, Geology
Placed on web Dec. 28, 2007; originally published Nov. 1948.
Comments to webadmin@kgs.ku.edu
The URL for this page is http://www.kgs.ku.edu/Publications/Bulletins/74/index.html