Fort Scott Limestone--(Swallow, 1866) Bennett, 1896
Three members, two limestones and a separating shale, have for a long time been recognized as comprising the Fort Scott limestone formation. For many years the lower limestone has been known as the "Cement rock" and the upper limestone has sometimes been called the "Lexington bottom rock." Recently the three members have been given formal geographic names. Named in ascending order the members are (1) Blackjack Creek limestone, (2) Little Osage shale, and (3) Higginsville limestone. The Houx limestone and Summit coal are names of beds in the Little Osage shale. The members in Kansas are described separately below.
A few years ago it was found that a lenticular limestone occurs a few feet below the Blackjack Creek limestone. This is the Breezy Hill limestone (Pierce and Courtier, 1938, p. 33), which seems to correspond cyclically to higher limestones that are included in the base of other Marmaton limestone formations. Where present it lies below black shale and coal which for many years have been regarded as being in the Cherokee shale. Because the "Cement rock" has for so long been regarded as the basal part of the Fort Scott limestone formation, because the black shale below it has for a long time been used to mark the top of the Cherokee shale, and because the Breezy Hill limestone is lenticular, it seems best not to amend the definition. However, observations in Craig and Rogers counties, Oklahoma (pl. 1, secs. 186, 188, 191, and 198), indicate that the Breezy Hill limestone may actually occur in a zone that is several cyclical deposits below the Fort Scott assemblage.
The top of the Fort Scott limestone is well defined and easily identified at the top of the Higginsville limestone. The top of the Fort Scott limestone is readily identified in the subsurface in eastern Kansas, but because of the local occurrence of the Breezy Hill limestone the base of the formation is not so easily detected in well records. The Fort Scott limestone has been identified along its outcrop line from Arkansas river valley in Oklahoma to southern Iowa. Equivalent beds are recognized in Illinois (Weller, Wanless, Cline, and Stookey, 1942, p. 1586, fig. 1).
In 1941, I (Jewett, 1941, p. 304) suggested that quarry exposures in the NE sec. 19, T. 25 S., R. 25 E., Bourbon County, Kansas, a short distance northeast of Fort Scott, be regarded as the type exposure of the Fort Scott formation. The exposure there is shown graphically in plate 1, section 72.
Graphic representations of outcrops of the Fort Scott limestone and adjacent rocks in Kansas and neighboring parts of Missouri and Oklahoma are shown in plate 1. Index numbers of sections in plates 1, 2, 3 and 4 correspond to numbers of stratigraphic sections at the end of this paper.
Fort Scott Limestone
Blackjack Creek Limestone Member--Cline, 1941
The Blackjack Creek limestone is the lower member of the Fort Scott limestone. It lies above black shale, which, according to present classification, is in the upper part of the Cherokee shale. The name Blackjack Creek was introduced by Cline (1941, p. 36). According to Cline, the type exposure of the Blackjack Creek limestone is in Johnson County, Missouri, "four miles southeast of Fayetteville and along Blackjack Creek."
Distribution--In Kansas the Blackjack Creek limestone crops out from northeastern Bourbon County to south-central Labette County (pl. 1).
Description--Where studied at the outcrops in Kansas, the Blackjack Creek limestone ranges in thickness from about 4 feet to 17.5 feet. In general it consists of two distinct limestones. The upper limestone has not been observed by me north of southern Bourbon County (pl. 1, secs. 74 and 101). The lower part of the Blackjack Creek limestone is the rock that has been called "Cement rock." This part generally weathers brown but it displays tan, brownish, and dark dove-gray colors when freshly exposed. It is generally earthy but in some exposures the rock is finely crystalline. Conchoidal fracture is rather common. The "Cement rock" is massive and its bedding is more regular than that of the upper part of the Blackjack Creek limestone. It contains few fossils. In northeastern Bourbon County the lower part of the Blackjack Creek limestone is divided by about one foot of calcareous shale (pl. 1, sec. 49). The measured thicknesses of the "Cement rock" part range from 1.55 feet in the NW sec. 11, T. 28 S., R. 24 E., Crawford County, to about 10 feet in the SE sec. 9, T. 34 S., R. 19 E., Labette County (pl. 1, sec. 172).
In many exposures the upper part of the Blackjack Creek limestone is easily distinguished from the lower part. The upper part, where present, is lighter gray, more coarsely crystalline, and more irregularly bedded. It is locally a mass of Chaetetes in the upper part (pl. 1, secs. 111, 117, and 149). This upper wavy-bedded Chaetetes-bearing part of the Blackjack Creek limestone is locally separated from the "Cement rock" by a thin shale parting (pl. 1, sec. 108).
The "Cement rock" is less pure limestone than the remainder of the Blackjack Creek limestone. A small amount of flint has been observed in the "Cement rock" in Labette County (pl. 1, sec. 172) and there is some flint in the upper part of the Blackjack Creek limestone in Rogers County, Oklahoma (pl. 1, sec. 186).
I have not seen the upper part of the Blackjack Creek limestone north of exposures in southern Bourbon County, Kansas; in many places in northern Bourbon County, in Linn County, and in eastern Missouri the Little Osage shale is in contact with the upper surface of the "Cement rock." Similar conditions prevail locally in northeastern Oklahoma. In many exposures in Oklahoma, however, the upper part is well developed. It is believed that the local absence of the upper part is due to nondeposition rather than to intraformational erosion. Measured thicknesses of the upper portion of the Blackjack Creek limestone range from about 7 to 13 feet.
With the exception of the rock-building corals, Chaetetes, which are almost if not entirely confined to the upper part, fossils are not especially abundant in the Blackjack Creek limestone. Fusulines are more commonly present in the upper part, but have been seen in the "Cement rock" in northeastern Oklahoma. Mollusks are plentiful in the "Cement rock" portion of this member in Oklahoma.
Fort Scott Limestone
Little Osage Shale Member--Jewett, 1941
The Little Osage shale separates the upper and lower limestones of the Fort Scott formation. The Houx limestone (Cline, 1941, p. 36) occurs in the Little Osage shale above the Summit coal. The type exposure of the Little Osage shale is in the NE SE sec. 2, T. 24 S., R. 25 E., Bourbon County, Kansas, A graphic section of that exposure is shown in section 49, plate 1. The type exposure of the Houx limestone is on the Houx ranch, Johnson County, Missouri (Cline, 1941, p. 36). The,name Summit was introduced as the name for this coal in Macon County, Missouri (McGee, 1892, p. 331).
Distribution--In general, outcrops of the Little Osage shale are near exposures of the limestone members of the Fort Scott formation. Locally, however, the Blackjack Creek limestone holds rather wide dip slopes, and the Little Osage shale and the Higginsville limestone occur a few miles west of the outcrop line of the lower member.
Description--In Kansas the thickness of the Little Osage shale at its outcrops ranges from about 4 to 12 feet. The thickest sections that I have measured are in Bourbon County. This member is generally thicker in northeastern Missouri than it is in Kansas.
In the northern part of the Kansas outcrop area and in eastern Missouri the Little Osage shale consists of five distinct units: (1) the lowermost part, light to dark-gray shale, locally calcareous, and about 3 feet thick; (2) the Summit coal bed, having a maximum thickness of about 1 foot; (3) shale, black and fissile, or gray in the lower part and black in the upper part, the black shale commonly containing coaly concretion-like masses; (4) the Houx limestone bed, about 1 foot thick in eastern Missouri and thinner in Kansas; (5) the uppermost part, gray calcareous shale, ranging in thickness from about 1 foot to 4.5 feet, the greatest known thickness being in Missouri. The Summit coal and Houx limestone beds have been identified as far south as the vicinity of Fort Scott, in Bourbon County. In northern Crawford County there is 2 feet of gray shale overlain by about 3 feet of black fissile shale, which in turn is overlain by about 1 foot of gray shale. Very probably these rocks are equivalent respectively to the lower, middle, and upper shale units (1, 3, and 5) as they are known farther north (pl. 1, secs. 72 and 108). Locally in southeastern Kansas and in northeastern Oklahoma the Little Osage shale is all or nearly all black fissile shale. Generally a few inches of gray shale occurs in the uppermost part. Black shale in this member commonly contains small black more or less spherical phosphatic concretions. In one place in Craig County, Oklahoma, cen. W. line sec. 36, T. 28 N., R. 19 E. (pl. 1, sec. 202), black limestone concretions are present in black shale. At the same place there is a thin limestone in the upper part of the Little Osage shale. This limestone probably is equivalent to the Houx limestone.
Large hard black limestone concretions which are common in black shale in the Cherokee rocks a short distance below the Blackjack Creek limestone have not been observed in the Little Osage shale. The Little Osage shale is not conspicuously fossiliferous. Cup corals occur in the upper few inches in some exposures in eastern Missouri, and conodonts are rather abundant in black shale portions.
Fort Scott Limestone
Higginsville Limestone Member--Cline, 1941
The upper member of the Fort Scott limestone is the Higginsville limestone. The name was introduced by Cline (1941, p. 36). According to Cline, the Higginsville limestone is well exposed east of Higginsville in Lafayette County, Missouri. No exact location of the type exposure has been published.
Distribution--At most points on the line of outcrop of the Fort Scott limestone the three members are exposed at the same place. Locally, however, the lower member, the Blackjack Creek limestone, holds dip slopes a few miles wide; hence the outcrops of the Higginsville limestone are west of those of the lower limestone. The line of outcrop of the base of the Fort Scott formation is shown in plate 1.
Description--The maximum measured thickness of an outcrop of Higginsville limestone in Kansas is about 15 feet. Its thickness across the state in the belt of its outcrop is seemingly rather constant (pl. 1). In many exposures the upper part has been removed by recent erosion or the lower part is covered by recent deposits. In isolated partial exposures of the Fort Scott limestone, the Higginsville member is distinguished with difficulty from the Blackjack Creek limestone. In its outcrop area low structural undulations cause topography to be of little value in correlation.
The Higginsville limestone is light to medium dark gray. It is commonly granular and crystalline. Much of it displays a brecciated appearance. Locally both the upper and lower parts are earthy in texture. In many places the upper part is a mass of fossil corals, Chaetetes. The beds in the lower part are generally massive, but as a rule the whole unit displays irregular wavy beds which are usually thinner in the middle part.
Giant fusulines are rather characteristic and are seen in many exposures. In places where the upper part of the rock is composed principally of Chaetetes, fusulines are entirely or almost entirely restricted to rock below the coral biostrome. Elsewhere fusulines are often seen in the upper part and project from the slightly weathered upper surface of the Higginsville limestone. Large crinoid stems and other fragments also are common. Brachiopods, including the common Marmaton genera, are more abundant in exposures in Oklahoma than in Kansas. Very minute fusulines are extremely abundant in the upper part of the Higginsville limestone in some exposures in Labette and Crawford counties.
Labette Shale--Haworth, 1898
The Labette shale includes beds between the Fort Scott and Pawnee limestones. It was named by Haworth and defined as occurring between the Oswego (Fort Scott) limestone and the Pawnee limestone (Haworth, 1898, p. 36).
The name "Peru sand" is commonly applied to sandstone bodies that occur in the Labette shale in the subsurface. The name Englevale was introduced by Pierce and Courtier (1935, pp. 10611064) for a sandstone in the Labette shale. Observations at numerous exposures along the outcrop line of the Labette shale from northeastern Oklahoma across Kansas and eastern Missouri indicate that the thick sandstone deposits in the vicinity of Warrensburg occur in the Labette shale. The name Warrensburg sandstone was introduced by Hinds and Greene (1915, p. 91) for the channel-filling sand body.
For a distance of a few hundred miles there is much sandstone in the Labette shale. The sand bodies are lenticular and at least in part are channel fillings. The disconformities at the bases of the sandstone lenses are not indicative of long periods of erosion. Mud, sand, and a very minor amount of coal and limestone were deposited in the areas of present outcrops. The several thin coal beds and limestone lenses indicate several cyclic deposits. Two massive sandstones separated by a limestone bed and shale occur in some exposures in eastern Oklahoma. Studies between eastern Kansas and Warrensburg, Mo., indicate that the Englevale and Warrensburg sandstones occur at about the same stratigraphic horizon.
The village of Labette in Labette County, Kansas, was designated as the type locality for the Labette shale (Haworth, 1898, p. 36). I designated the somewhat poor exposure beginning near the center of the north line and extending to a point near the northeast corner of sec. 22, T. 32 S., R. 20 E., near the town of Labette, as a pro tempore type exposure. There are at present no good exposures of the Labette shale known near Labette.
Distribution--The outcrop line of the Labette shale in Kansas is between the sinuous outcrop of the bounding limestones. The belt ranges in width from a small fraction of a mile to a few miles. The lines of outcrop of the bases of the two limestones are shown in plates 1 and 2. The line shown in plate 2 as the outcrop line of the base of the Pawnee limestone is also the outcrop line of the top of the Labette shale.
Description--Changes in thickness of the Labette shale along its line of outcrop in Kansas are rather abrupt. According to measured sections, the thickness range is between about 30 and 100 feet. Sections measured at locations about 1 mile apart in northeastern Bourbon County show a difference of 20 feet in thickness. According to measurements I have made at outcrops and to logs of wells drilled a short distance west of the outcrops, the Labette shale is thickest in Labette County and thinnest in Bourbon County. Thus, the thickness increases southward.
The Labette shale includes clay and silt shale, sandstone, and minor amounts of limestone and coal. There is a persistent limestone in the upper-middle part in southeastern Kansas. This is very probably the same limestone that occurs in the same part of the Labette shale over a wide area in northeastern Oklahoma. It is especially well developed in Craig County. Although the formation contains much sandstone in Kansas, sandstone is not as important quantitively in the Kansas outcrop sections as in exposures in Oklahoma and Missouri. There are several coal beds in the Labette shale. All are of more or less local occurrence, but it is believed that they represent coal phases of definite cyclothems. One coal bed occurs near the base in a zone that is more commonly occupied by black shale alone or by black shale and a very thin coal bed. The black shale zone in the basal part of the Labette shale is especially well developed in southeastern Rogers County, Oklahoma, near the place where the underlying Fort Scott limestone pinches out or grades laterally into clastic deposits (pl. 1, sec. 187). This facies is rather persistent and has been observed in several Kansas exposures. Another coal bed near the middle part is seemingly less persistent. A black shale and coal zone occurs in the upper part of the Labette shale next below the persistent thin limestone that marks the base of the Pawnee limestone. This coal in the upper part has been seen at several places along the line of outcrop from Labette to Linn County. Locally, however, black shale in this zone does not contain a bed of coal, and in a few places the black shale facies is absent.
Sandstone lenses, perhaps in part channel fillings, are common in the Labette shale although less common in Kansas than in Missouri and Oklahoma. Limestone conglomerates occur in the basal part of some of the sand bodies in Missouri but they have not been observed in Kansas. In Missouri the Warrensburg channel sandstone is believed to occur in the Labette shale. It fills a channel that locally is cut below the Fort Scott limestone. The top of the channel fill in the vicinity of Warrensburg seems to be in the lower middle part of the Labette shale at approximately the same horizon that marks the top of sandstone bodies in Kansas. A few inches of sandstone occurs about 25 or 30 feet above the base of the formation in several exposures in Kansas. There are two very important sandstone horizons in the Labette shale in Oklahoma. It is believed that the lower of the two sandstones occupies the same stratigraphic position as the Warrensburg sandstone. The Englevale sandstone in Crawford County, Kansas, lies in the same position.
A nearly complete Labette shale section is exposed near the center of the north line of sec. 16, T. 25 S., R. 24 E., Bourbon County, Kansas. There the lower coal bed lies about 2 feet above the Higginsville limestone, the upper member of the Fort Scott formation. A zone of thin sandy limestone and sandstone is present about 12 feet from the base of the Labette shale, which there is about 39 feet thick. The upper part of the section is chiefly gray and yellow shale. At an exposure about 1 mile distant, in the SW cor. sec. 15, T. 25 S., R. 24 E., the formation is about 54 feet thick and no sandstone was seen. A thin and impure limestone occurs in the upper middle part.
The sections described above are rather characteristic of the less sandy facies of the Labette shale. In northeastern Bourbon County there are three thin limestones in the middle part of the formation. The lower two are separated by about 7 feet of shale and the upper one is about 18 feet higher than the middle limestone. The lower limestone is a brachiopod-bearing rock about 1 foot thick. It lies on a thin coal bed, below which is 6 feet of carbonaceous shale resting on the Warrensburg sandstone. The upper two limestones are very thin and are cross-bedded. They seem to be detrital limestones, but are believed to have been formed from wave or current-washed shell fragments and precipitated masses rather than from fragments of a pre-existing rock.
The top of the Warrensburg or Englevale sandstone lies in a zone about 20.or 30 feet above the base of the Labette shale. The thicknesses of these sand bodies in Kansas range from a featheredge to about 30 feet.
Pawnee Limestone--(Swallow, 1866) Moore, 1936
The Pawnee limestone lies between the Labette and Bandera shales; hence it is the first prominent limestone assemblage above the Fort Scott limestone. It generally has been described as comprising a single ledge, and Swallow (1866) applied the name Pawnee to "heavy bedded, porous and compact, coarse and fine, drab, brown and bluish-gray, cherty, concretionary and mottled (limestone), 20 to 25 feet thick." It is now known that the Pawnee limestone is divisible into members (Jewett, 1941, p. 315). The following members, named in ascending order, are recognized: (1) Anna shale, (2) Myrick Station limestone, (3) Mine Creek shale, and (4) Laberdie limestone.
The inclusion of a shale member at the base of a limestone formation is rather unusual. There is a thin slabby and locally lenticular limestone at the base of the Anna shale over a very wide area. This limestone is so thin in Kansas, nowhere more than 2 or 3 inches, that it does not seem deserving of a name and designation as a member. In Missouri and Oklahoma, however, limestone at the base of the persistent black shale that comprises most of the Anna member is much thicker. In Oklahoma, this limestone probably comprises the greater part of the thick Oologah limestone (Jewett, 1941, p. 290). It is clear that this basal limestone and the overlying shale belong in the Pawnee limestone assemblage. In 1936 Moore (1936, p. 62) amended the definition of the Pawnee limestone to include the thin limestone bed discussed above (Jewett, 1941, pp. 312-315).
The Pawnee limestone is easily identified in well logs in all of eastern Kansas. It is identified in Oklahoma (pl. 2) and comprises all, or at least the main part, of the Oologah limestone that crops out a few miles east of Tulsa. It has been traced across Missouri into Iowa (Cline, 1941, p. 37; Jewett, 1941, p. 312) and its equivalent is recognized in Illinois (Weller, Wanless, Cline, and Stookey, 1942, pp. 1591, 1592).
Because the type exposure of the Pawnee limestone had not been definitely located, I (Jewett, 1941, p. 315) designated an exposure along state highway 7, slightly north of the center of sec. 7, T. 27 S., R. 24 E., Bourbon County, Kansas, as the type. The exposure there is shown graphically in plate 2, sec. 97.
Graphic sections of outcrops of the Pawnee limestone and adjacent rocks in Kansas and in neighboring parts of Missouri and Oklahoma are shown in plate 2.
Anna Shale Member--Jewett, 1941
The Anna shale is the lower member of the Pawnee limestone formation. It lies below the Myrick Station limestone and in Kansas includes at its base a thin bed of dark limestone. The commercially important Lexington coal of Missouri occurs in the Anna shale. The type exposure of the Anna shale is the same as that of the Pawnee limestone; that is, a little north of the center of sec. 7, T. 27 S., R. 24 E., Bourbon County, Kansas, on Kansas highway 7.
Distribution--The outcrop of the base of the Pawnee limestone or the base of the Anna shale is shown in plate 2. The line of outcrop is a sinuous line from eastern Linn County to Labette County.
Description--Along its line of outcrop in Kansas, the Anna shale member of the Pawnee limestone ranges in thickness from about 2 feet to approximately 12 or 13 feet. Changes in thickness are rather abrupt. It must be remembered, however, that the Anna shale comprises black shale and thin-bedded limestone facies of strata below the more strictly defined Myrick Station limestone and hence its lower boundary does not mark a definite stratigraphic horizon.
In Kansas the Anna shale consists chiefly of black and generally fissile shale. It commonly contains small black nearly spherical phosphatic concretions imbedded in black shale. In nearly all exposures the upper few inches consists of gray shale. This upper gray shale zone ranges in thickness from a few inches to approximately 2 feet. Locally the upper gray zone is absent (pl. 2, secs. 116 and 119). With few exceptions, careful searching in places where the basal part of the Pawnee limestone is well exposed reveals a thin bed of slabby black crystalline or earthy limestone below the thicker black shale part of the Anna member. This limestone is in the closing part of the marine phase of a lower Pawnee cyclothem which is rather fully developed in Nowata County, Oklahoma (pl. 2, sec. 193). There the Pawnee limestone assemblage includes limestone lower than this lower Anna bed of Kansas and eastern Missouri.
The Lexington coal, economically important in Lafayette County, Missouri, occurs in the Anna shale. The basal black limestone described above is present over wide areas in Missouri and has been identified in Missouri below the Lexington coal. Locally in Crawford County, Kansas, the upper middle part of the Anna shale is very coaly and may be described as nearly coal (pl. 2, sec. 119). Elsewhere in Crawford County, concretionary-like masses of coaly material occur in the upper part of the Anna shale (pl. 2, sec. 67). A coal bed 0.1 feet thick in Craig County, Oklahoma (pl. 2, sec. 203), is approximately at the horizon of the Lexington coal bed. The Lexington coal has been seen in Missouri in several Anna shale exposures between the type locality of the coal, near Lexington, Mo., and eastern Kansas.
The Anna shale is not conspicuously fossiliferous. Fragments of crinoids and other fossils occur in the basal limestone, and flattened brachiopod shells occur locally in the black shale.
Myrick Station Limestone Member--Cline, 1941
The Myrick Station limestone is the second member from the base in the Pawnee limestone in Kansas. The name was applied by Cline (1941, p. 37) to the "Lexington cap-rock" in its exposure near Myrick Station on Missouri river in Lafayette County, Missouri. The same limestone is easily identified in numerous exposures in Lafayette, Johnson, Cass, and Bates counties, Missouri, and Linn County, Kansas. Cline (1941, p. 37) designated the exposures in ravines in the south bluff of Missouri river near Myrick Station, Lafayette County, Missouri, as the type exposure of the Myrick Station limestone.
Distribution--The distribution of the outcrops of Myrick Station limestone in Kansas is almost exactly the same as that of the underlying Anna shale (pl. 2).
Description--At outcrops in Kansas, the Myrick Station limestone ranges in thickness from less than 1 foot to approximately 8.5 feet. The greater thicknesses are due to the presence locally of Chaetetes biostromes which occur more commonly in the upper part.
The lower part of the Myrick Station limestone has a rather uniform thickness ranging between approximately 3 and 4 feet. This lower part is characteristically dark brownish-gray or dove-gray limestone that weathers tan or brown. This part is massive and is regularly bedded. Locally a large portion is composed of Chaetetes colonies, but these corals are not characteristic.
Generally where in excess of approximately 4 feet in thickness, the upper part of the Myrick Station limestone is a Chaetetes biostrome. Algal limestone is also abundant. In sec. 11, T. 25 S., R. 24 E., Bourbon County, a Chaetetes mass is separated from the lower massive part of the Myrick Station limestone by a thin shale bed. The coral mass there is overlain by 0.5 foot of slabby noncoralline limestone. Crinoid fragments, brachiopods (notably Squamularia), and sparse fusulines are other plentiful fossils in the Myrick Station limestone.
Mine Creek Shale Member--Jewett, 1941
North of Marmaton river in Kansas, and in Missouri, the Pawnee limestone includes a definite shale unit between the Myrick Station and Laberdie members. This is the Mine Creek shale (Jewett, 1941, p. 318). South of Marmaton river the Mine Creek shale is thin, but it can be identified in many exposures. The type exposure of the Mine Creek shale is near the middle of the south side of sec. 23, T. 21 S., R. 25 E., on a tributary of Mine creek in Linn County, Kansas. The type exposure is represented graphically in plate 2, section 10.
Distribution--Because the overlying Laberdie limestone generally lies next below the soil in extensive dip slopes bordered on the east by the Pawnee limestone escarpment, the line of outcrop of the Mine Creek shale is almost exactly the same as that of the basal members of the Pawnee formation (pl. 2).
Description--Measured thicknesses of the Mine Creek shale in Kansas range from a featheredge to about 17 feet. The thickest Kansas outcrop sections are in the northern part of the outcrop belt. In eastern Missouri this member of the Pawnee limestone has a thickness comparable to that in near-by Kansas counties. In northeastern Oklahoma the thickness is commonly less than 1 foot (pl. 2).
The Mine Creek shale consists of gray, black, and greenish-gray and yellow shale and a minor amount of limestone. In one exposure in Johnson County, Missouri, a thin sandstone bed occurs in the middle part (pl. 2, sec. 185). Locally in Bates County, Missouri, the Myrick Station limestone, which normally underlies the Mine Creek shale, seemingly is absent, but the upper part of the Mine Creek shale is readily identifiable there because of its fauna consisting chiefly of numerous brachiopods. In the shallow subsurface in central Bates County, this member has a thickness ranging from 8 to 11 feet, of which locally 7 feet is fine-grained sandstone. At several exposures in Linn and Bourbon counties, Kansas, the Mine Creek shale is divisible into three parts--two shale deposits separated by a thin bed of limestone. Where thickest and where better exposed, the lower shale unit is yellowish and greenish-gray and is limonitic. Limonite occurs in small concretions and stringers. The upper shale is highly fossiliferous. It contains an extensive fossil zone that allows identification of the unit in areas where the underlying limestone is not seen. This brachiopod zone in the upper part of the Mine Creek shale is exposed in numerous places in Bates, Cass, and Johnson counties, Missouri, as well as in Linn County, Kansas. The upper fossiliferous part is calcareous and contains small limestone nodules. It is probable that the limestone in the middle part of the Mine Creek shale is not the same bed in various exposures. Locally in Linn County, Kansas, this limestone is a coquina of brachiopods.
In the southern part of Bourbon County and in Crawford and Labette counties the Mine Creek shale is merely a thin shale bed between the Myrick Station and Laberdie limestones, which, however, are distinguishable one from the other because of lithologic differences. Locally in Crawford County the Mine Creek shale is about 1.5 feet thick; the upper part is gray and blocky and the lower part is black and platy shale. As noted above, in the northern part of the outcrop belt in Kansas the upper part of the Mine Creek shale is abundantly fossiliferous. Chonetids are the most plentiful fossils.
Laberdie Limestone Member--Jewett, 1941
The uppermost member of the Pawnee limestone is the Laberdie limestone (Jewett, 1941, p. 320). North of Marmaton river in Kansas, it is distinctly separated from the Myrick Station limestone by several feet of shale. The same condition exists in Missouri. Farther south in Kansas and in Oklahoma, the separating shale (Mine Creek) is thinner and may be locally absent, but in many exposures the underlying darker more massive Myrick Station limestone can be differentiated from the lighter colored more crystalline and thinner bedded Laberdie limestone. The type exposure of the Laberdie limestone is mostly artificial. It is in a quarry in the southwestern part of sec. 6, T. 23 S., R. 25 E., 1 mile west of Prescott, Linn County, Kansas. Laberdie creek is a short distance west of the quarry.
Distribution--The Laberdie limestone underlies dip slopes ranging up to a few miles in width. Outcrops of at least the basal part of the limestone generally occur with the lower Pawnee members along the line shown in plate 2.
Description--It is difficult to make accurate measurements of the thickness of the Laberdie limestone at many of the outcrops. In the northern part of the outcrop area in Kansas the thickness is approximately 10 feet. In the southern part it is much greater, the average being perhaps 20 or more feet.
In general the Laberdie limestone is light gray, crystalline, and brecciated. It occurs in rather thin wavy beds or beds of irregular thickness. Commonly the lower part is somewhat more massive. Locally it is in part a Chaetetes biostrome. Coralline limestone is more plentiful in the upper part. Fossils, particularly the abundant corals, are frequently partly or wholly silicified, but flint nodules are rare or entirely absent. This statement is contrary to a more or less prevalent belief that the Pawnee limestone is a flinty rock. Commonly large fragments of weathered flint from higher strata have accumulated on the escarpments of the Pawnee limestone and other rocks, giving the erroneous impression that the scarp-making rock is flint bearing.
In much of the Kansas outcrop area the Laberdie limestone lies below extensive dip slopes. In such areas the soil mantle is thin, and bare outcrops are common in places of small relief as well as along drainage channels. A large part of the area underlain by the Laberdie limestone is unplowed grassland. Terrain of this kind is characteristic in Bourbon County.The upper part of the Laberdie limestone weathers into a mass having an irregular hummocky upper surface. The whole unit consists of limestone that generally becomes lighter in color upon weathering. This rock is often called the "cotton rock." Weathered surfaces are pitted and flecked with brown. Sparse fusulines, crinoid and echinoid fragments, and brachiopods, in addition to abundant Chaetetes, are somewhat characteristic of the Laberdie limestone. With the exception of the coralline facies, however, it is not a highly fossiliferous rock. Exposures of the Laberdie limestone in Oklahoma are more fossiliferous than those in Kansas. Silicified specimens of Cystauletes mammilosus King, a cylindrical sponge, are locally abundant.
Bandera Shale--Adams, 1903
The Bandera shale is a relatively thick clastic deposit that lies above the Pawnee limestone and below the Altamont limestone. It was named by Adams (1903, p. 32) from exposures near the former railroad station of Bandera, in Bourbon County, Kansas.
The Bandera formation includes a definite zone of sandstone to which the name Bandera Quarry sandstone has been applied (Jewett, 1941, p. 292). Near the base of the formation is a bed of coal which is persistent from the southern part of Bourbon County, Kansas, northward into Missouri. Coal is found in the same position in the subsurface in eastern Nebraska (Condra and Reed, 1943, p. 55). This is the Mulberry coal, named by Hinds (1912, p. 75) from exposures along Mulberry creek in Bates County, Missouri, not far east of Linn County, Kansas.
A continuous and complete section of the Bandera shale is not exposed in the vicinity of old Bandera station, in sec. 29, T. 25 S., R. 23 E., Bourbon County, Kansas. The upper approximate 20 feet of the Bandera shale and the overlying Altamont limestone are exposed in the NW SW of the section, and nearly all the local occurrence of the Bandera Quarry sandstone is exposed in the flagstone quarries in the vicinity of the center of the north line of the southwest quarter of the section (pl. 3, secs. 60 and 61). The exact type exposure of the Mulberry coal has not been designated, but it is assumed to be in the mining district along Mulberry creek southeast of Amoret, Bates County, Missouri.
Distribution--The Bandera shale and sandstone underlie a belt of varying width between the outcrops of the Pawnee and Altamont limestones extending in Kansas from Labette County to Linn County. A prominent anticlinal dome in the vicinity of Mound City, Linn County, has given rise to an inlier of Bandera shale and the bounding limestones there.
Description--The Bandera shale is variable in thickness. It is similar in this respect to the Labette and Nowata shales. Along the outcrop line in Kansas the thickness ranges from about 35 to about 75 feet. Available records of some rather closely spaced bore holes a short distance down dip from the outcrops show variations in thickness that are of interest because of their probable relationship to the present drainage pattern of the area. In northeastern Linn County and in Bates County, Missouri, there seems to be an abrupt change in thickness of the Bandera shale at about the present position of Marais des Cygnes river. North of the river the average thickness is about 22 feet and is as little as 8 feet in central Bates County. For a few miles south of the river the common thickness is about 45 feet and the known maximum is 52 feet. South of Little Osage river in northern Bourbon County, measured subsurface thicknesses range from about 47 to 96 feet.
The Bandera shale includes clayey and sandy shale, sandstone, and a minor amount of coal and limestone. The shale is mostly light in color. There is a very persistent zone of rather bright purplish or maroon shale in the upper part. Concretions and small lenses of limonite are characteristic of this facies. Septarian limestone concretions occur locally in the same facies.
The Mulberry coal bed is in the lower part of the Bandera shale at a position that ranges from a few inches to about 6 feet above the base of the formation. This coal bed has not been identified south of a point in southern Bourbon County, Kansas, but it extends far to the north. Locally in Linn County, Kansas, and in Bates County, Missouri, the Mulberry coal is more than 2 feet thick. It is extensively mined in these places. Recently Condra and Reed (1943, p. 55, fig. 19) have noted the presence of a coal bed in the lower part of the Bandera shale in the subsurface in eastern Nebraska. A very local coal bed occurs near the top of the Bandera shale in Labette County, Kansas.
Shale that separates the Mulberry coal from the underlying Laberdie limestone is distinct lithologically from the remainder of the Labette shale. This shale is not sandy, is less limonitic, and is slightly carbonaceous. It has some of the characteristics of an underclay and is often called "fire clay." Chemical analyses made in the Survey laboratories show that this shale has an alumina (Al2O3) content of 20.02 percent.
Sandstone and sandy shale are plentiful in the Labette formation. A part of the sandstone occurs as channel fillings. In some places clean cut lateral contacts between clay shale and sandstone have been studied. Elsewhere the sandstone grades laterally through sandy shale into clay shale without sand. The tops of sand bodies, at least a part of which are channel fillings, are in the upper and middle part of the formation. Locally in Kansas and in eastern Missouri, sand bodies occur next below the Altamont limestone, and locally the entire Bandera section is sandstone. In Kansas channel fillings are not known to extend into strata below the top of the Pawnee limestone. Locally in Missouri, filled channels reach downward into the Pawnee rocks. At one place, in the NW sec. 2, T. 15 N., R. 28 W., Johnson County, Missouri, a channel filled with sandstone and limestone conglomerate is cut to a level about 5 feet above the top of the Myrick Station limestone. The Laberdie limestone and the upper part of the Mine Creek shale can be seen at a place a few feet away from the wall of the filled channel. The top of this coarse clastic channel filling was not observed there, but the channel filling is believed to be a part of the Bandera formation. In the same vicinity the base of the Hepler sandstone (basal Missourian) rests on shale in the upper part of the Bandera formation and a few feet above the top of a Bandera sandstone body.
Sandstone bodies that collectively are called Bandera Quarry sandstone occur in the Bandera shale in Kansas. This sandstone is commonly well bedded and is fine and micaceous. Locally it is cemented with siliceous material. Locally the Bandera Quarry sandstone occupies the entire Bandera section. Where present, it is generally separated by shale ranging in thickness from a few to 20 or more feet. The Bandera Quarry sandstone has been quarried for a long time in Bourbon County. Beautiful flagstones and building stone are produced. In the exposures in a quarry in the SW sec. 29, T. 25 S., R. 23 E., this sandstone is about 30 feet thick. For the most part, it is well bedded and contains an abundance of fossil worms.
A thin bed of nearly black limestone occurs locally in the lower part of the Bandera shale just above the Mulberry coal. This limestone and the underlying coal are exposed in sec. 1, T. 26 S., R. 23 E., Bourbon County, Kansas. Limestone has been noted in well records at the same stratigraphic horizon in northern Linn County and in eastern Missouri.
The Bandera shale contains few invertebrate fossils. Annelid worms in the Bandera Quarry sandstone have been -noted above. Fragments of land plants are abundant in sandy shale and sandstone, especially in the lower part of the formation, but above the Mulberry coal. Carbonaceous masses in the shale below the Mulberry coal probably are the partly coalified fragments of plants.
Graphic representations of several Bandera shale outcrops in Kansas are shown in plate 3.
Altamont Limestone--Adams, 1896
The Altamont limestone lies next above the Bandera shale; it comprises limestone and shale beds. These are best developed in Kansas in southeastern Neosho and Labette counties, and they are equally well developed locally in Bates County, Missouri.
For a long time the Altamont limestone, like the Pawnee and Lenapah limestones, was described and represented in diagrams as a single limestone ledge. Seemingly one limestone member and then another had been seen at outcrops, but two had not been noticed at one outcrop or the very persistent middle shale member had perhaps been assumed to be of local occurrence. Observations have shown, however, that the separating shale is very widespread and that the three members can be identified from northeastern Oklahoma to southern Iowa and into Illinois (Cline, 1941, pp. 26, 27; Jewett, 1941, p. 326; Weller, Wanless, Cline, and Stookey, 1942, p. 1586). They can be recognized in the subsurface in much of eastern Kansas. I have used the persistent and easily recognized Lake Neosho shale as the basis of division into members (Jewett, 1941, p. 326). All limestone within the formation and above the Lake Neosho shale is called Worland, and the limestone below, locally composed of as many as four distinct beds, is assigned to the Tina member.
No exposures in the vicinity of Altamont that show the whole Altamont formation are known. The Lake Neosho shale, a part of the overlying Worland limestone, and a part of the underlying Tina limestone are exposed near the center of the west line of sec. 5, T. 33 S., R. 19 E., about 3.5 miles west of Altamont, Labette County, Kansas. This exposure has been designated as the type exposure (Jewett, 1941, p. 326). The exposure there is shown graphically in plate 3, section 160.
Graphic sections of outcrops of the Altamont limestone and adjacent rocks in Kansas and in neighboring parts of Missouri and Oklahoma are shown in plate 3.
Tina Limestone Member--Cline, 1941
Tina limestone is the name of the lowest member of the Altamont limestone. The name was introduced by Cline (1941, p. 43), and I (Jewett, 1941, p. 329) proposed that it be used for all limestone in the Altamont formation below the Lake Neosho shale. Cline designated exposures in the west-central part of sec. 7, T. 54 N., R. 22 W., Carroll county, Missouri, as the type of the Tina limestone.
Distribution--The Tina limestone is locally absent in some exposures of the Altamont formation in Linn and Bourbon counties. The upper part, however, is present almost continuously along the line shown in the map of southeastern Kansas in plate 3. All phases of the member are well developed in Labette and southeastern Neosho counties.
Description--According to measurements made at a great many outcrops, the Tina limestone in Kansas ranges in thickness from a featheredge to slightly more than 10 feet. Like several other Marmaton limestones, it is locally largely a Chaetetes biostrome, and its thicker developments locally are due to the presence of the remains of these Desmoinesian rock-building corals. In general, the lower member of the Altamont limestone is more fully developed in the southern part of its outcrop belt than in the northern part, but changes in thickness are somewhat abrupt (pl. 3). Locally the Tina limestone is absent (pl. 3, secs. 25, 36, 43, 82, and 95). In some exposures it is seen to pinch out or to grade laterally into sandstone (pl. 3, secs. 10 and 35).
In places where it is more fully developed, the Tina limestone is composed of two or three limestones separated by thin shale beds (pl. 3, secs. 127, 128, 129, 132). The exposure in the SW sec. 23, T. 30 S., R. 20 E., Neosho County, shows clearly its full development. There the basal part consists of 0.75 foot of gray mottled wavy-bedded limestone containing Mesolobus. This is overlain by a thin shale bed. The second limestone from the base is really two rocks. The lower one is gray, nodular, and brecciated. In its upper part are pelecypods and "Fistulipora." Fusulines are rather abundant in its lower part and crinoid fragments are plentiful throughout. This lower part is a little more than 2 feet thick. The upper rock of this second limestone unit is massive and contains crinoid remains and brachiopods. Next above is a thin shale overlain by 1.5 feet of bluish-gray to purplish-brown limestone which occurs in thin irregular beds and contains many crinoid fragments.
The upper unit described above is the most persistent part of the Tina limestone, and it extends far northward across Missouri into Iowa. Along most of this distance the other parts are absent but are developed locally. Where this persistent part alone is present in Kansas it is generally less than 1.5 feet thick, is granular, and contains a molluscan fauna and plentiful algal remains. Locally it is almost entirely an algal limestone. Cross-bedding is common. At some places it is a mass of fossil fragments that have seemingly suffered much abrasion by waves or currents. Locally it grades laterally and vertically into sandstone. Ostracodes are abundant in this rock in Bates County, Missouri.
Although one or more of the units of the Tina limestone that are described above can be recognized in many exposures, nearly the entire member is a Chaetetes biostrome in Labette County. The coral mass, however, wherever seen, lies on at least a few inches of noncoralline limestone. Evidently Chaetetes did not thrive on mud bottoms.
Lake Neosho Shale Member--Jewett, 1941
The Lake Neosho shale is the middle member of the Altamont limestone. It is very persistent and is identified in exposures where the underlying Tina limestone is absent. Because of its easily recognized characteristics, particularly the presence of rough irregular phosphatic concretions, it is conveniently used as the basis of subdivision of the Altamont limestone into members. The type exposure of the Lake Neosho shale is southeast of Neosho County State Park, in the SE sec. 23, T. 30 S., R. 20 E., Neosho County, Kansas (pl. 3, sec. 132).
Distribution--The Lake Neosho shale is present with the overlying Worland limestone and, except in a very few places, with the underlying Tina limestone along the line shown in the map of southeastern Kansas in plate 3.
Description--The thickness of the Lake Neosho shale is rather uniform over wide areas. The characteristic thickness is about 2 feet. Locally, however, it is nearly 6 feet thick. The Lake Neosho shale is the most easily recognized member of the Altamont limestone. It can be differentiated from the underlying Bandera shale in outcrops where the Tina limestone, which normally separates the two shales, is absent. The Lake Neosho shale chiefly includes yellowish-gray and black shale. Where the unit is rather thin, it is dominantly light in color but black shale is found almost without exception in the lower or middle part. Irregularly shaped slightly elongated rough dark phosphatic concretion-like nodules are invariably present in the dark-gray or black shale beds. These nodules are the most characteristic feature of the unit. They commonly contain teeth and bone fragments, and probably are coprolites.
Worland Limestone Member--(Greene, 1933) Cline, 1941
The Worland limestone is the upper member of the Altamont limestone. It is known from Oklahoma to Iowa, and an equivalent limestone seems to be present in Illinois. The name Worland has been used for several years but only recently has a definition been offered (Cline, 1941, p. 29; Jewett, 1941, p. 334). I have designated as the type exposure of the Worland limestone the exposure along the Kansas City Southern railway just north of a grade crossing northeast of Worland, Bates County, Missouri (Jewett, 1941, p. 334).
Distribution--In Kansas the Worland limestone makes a somewhat prominent outcrop and escarpment from eastern Linn County to southwestern Labette County.
Description--The Worland limestone in Kansas has a rather uniform thickness of about 8 feet, although it is generally somewhat thinner in the northern part of its outcrop area. This upper member of the Altamont limestone is somewhat less easily divided into parts based on lithologic differences than are several of the other Marmaton limestones. In general it is rather light bluish-gray in color and is massive; it is finer grained than are other limestones of the Marmaton group. Specimens from many exposures have the characteristics of lithographic limestone. In some places the lower part is brecciated. Chemically, the Worland limestone is usually purer calcium carbonate than other rocks of this group. Samples are frequently found to be approximately 97 percent pure. In one exposure, in the SW sec. 23, T. 30 S., R. 20 E., Neosho County, Kansas (pl. 3, sec. 132), the rock consists of light bluish-gray limestone and thin lenses of nearly white flint.
One of the most comprehensive exposures of the Worland limestone in Kansas is in a small quarry in the SE sec. 24, T. 25 S., R. 22 E., a short distance east of Uniontown, Bourbon County. There the lower 7 feet includes slightly nodular dense and slightly crystalline gray limestone containing fossil brachiopods. This is the part of the Worland limestone that is persistent over wide areas. Next above is about 2 feet of bluish-gray, nodular, rather thin-bedded limestone, in which are enclosed domelike masses of well-bedded shale. Some of the shale-filled "cavities" are 6 feet long and 1.8 feet high. The shale filling rests on the underlying limestone unit described above. The included shale masses are calcareous and contain many small limestone nodules and fusulines. The rock containing the shale-filled cavities is overlain by about 2 feet of interbedded nodular limestone and calcareous shale. The exposure described here is represented in plate 3, section 52.
The Worland limestone holds a prominent escarpment and extensive dip slope in southeastern Kansas. Because it is the only relatively thick limestone in a belt several miles wide, it is extensively quarried for road material and other uses.
Chonetids, Squamularia, Composita, and other brachiopods, and fusulines are characteristic of the Worland limestone. In many exposures fusulines are rather uniformly distributed throughout the persistent part of the rock, and they are abundant in the locally occurring upper part.
Nowata Shale--Ohern, 1910
Shale and sandstone that lie between the. Altamont and the Lenapah limestones were called Nowata shale by Ohern (1910, p. 23). I have suggested the name Walter Johnson sandstone for included sand bodies (Jewett, 1941, p. 335). The Nowata derives, its name from the city of Nowata, Nowata County, Oklahoma. The type exposure of the Walter Johnson sandstone is in sec. 10, T. 35 S., R. 17 E., Montgomery County, Kansas.
Distribution--In general the band of outcrop of the Nowata shale is narrow, but because of the rather wide dip slope held by the Worland limestone the line of outcrop is commonly a few miles west of the outcrop of the basal part of the Altamont formation.
Description--Along its line of outcrop in Kansas, the Nowata shale ranges from almost nothing to approximately 50 feet in thickness. Measured sections indicate rather abrupt thickness changes.
The Nowata shale includes light and dark clay shale, sandy shale, and sandstone. Unlike the Labette and Bandera shales, no coal beds are known in the Nowata in Kansas. It seems that genetically the dark and black shale (pl. 4, secs. 180, 92, and 143) between the Worland limestone and the Norfleet limestone belong with the Lenapah rock assemblage rather than with the lighter colored and locally sandy Nowata strata, but because of the continuity of the bounding limestones it seems hardly expedient to exclude these darker beds from the Nowata formation.
In general the Nowata shale is light gray, yellow, and limonitic. Locally it is almost or entirely free from sand. At places it is sandy shale or contains massive sandstone bodies. The sandstone and sandy shale are abundantly micaceous. Dark and black shale in the formation commonly contains small smooth dark phosphatic concretions which are quite unlike the phosphatic nodules that occur so abundantly in the Lake Neosho shale but similar to those in black shales in the Fort Scott and Pawnee formations. Generally the Nowata shale is almost free from fossils, but brachiopods are common in places where the dark shale facies is developed. In Bates County, Missouri, Mesolobus sp., other chonetids, and large productids are abundant.
Lenapah Limestone--Ohern, 1910
The Lenapah limestone overlies the Nowata shale. It was named by Ohern (1910, p. 23) from the town of Lenapah in Nowata County, Oklahoma. Like other Marmaton limestone formations, the Lenapah is divisible into members. The upper member is the Idenbro limestone; the middle member is the Perry Farm shale; and the lower member is the Norfleet limestone. The type exposure of the Lenapah limestone is in an old quarry in the NW NE sec. 30, T. 28 N., R. 16 E., Nowata County, Oklahoma. This is at Bell Spur, a short distance north of Lenapah. Newer quarries a short distance southeast of Bell Spur now offer better exposures (pl. 4, sec. 200).
Weller, Wanless, Cline, and Stookey (1942, fig. 1) recognized the equivalent of the Lenapah limestone in southern Iowa and western Illinois. According to their correlation in Illinois, the Lonsdale limestone and overlying beds, including strata that are correlated with Exline limestone of northern Missouri, are equivalent to the Lenapah limestone. In Iowa, the Cooper Creek limestone, the Exline limestone, and separating shale beds are correlated with the Lenapah beds. The Exline limestone has commonly been called the "Trepospira zone." Thus it seems that the correlation of the Exline limestone or "Trepospira zone" and the upper part of the Lenapah limestone (Idenbro limestone) is well founded (Weller, Wanless, Cline, and Stookey, 1942, p. 1592). In Bates County, Missouri, Trepospira sp. occurs rather abundantly in the upper part of the Perry Farm shale.
Graphic sections of 46 outcrops of the Lenapah limestone and adjacent rocks are shown in plate 4.
Norfleet Limestone Member--Jewett, 1941
The lower part of the Lenapah limestone, below the nodular and locally fossiliferous shale in the middle part, is the Norfleet limestone. Its definition (Jewett, 1941, p. 338) is such as to include all limestone and shale beds of the Lenapah formation below the easily defined Perry Farm shale. From the definition it follows that the Norfleet limestone is absent or is very poorly developed in much of the outcrop area in southeastern Kansas, but wherever limestone underlies the nodular Perry Farm shale it is assigned to the Norfleet member. The type exposure of the Norfleet limestone is in the SE sec. 35. T. 32 S., R. 18 E., Labette County, Kansas. The section there is shown graphically in plate 4, section 143.
Distribution--The Norfleet limestone is a less persistent part of the Lenapah formation and hence it is not everywhere present along the line of outcrop of the formation shown on plate 4. It is best developed in the southern part of the area of outcrop and is rather poorly developed locally in the northern part (pl. 4).
Description--The Norfleet limestone, although not persistent, is a zone that can be readily identified along a line that extends from northeastern Oklahoma at least as far northeast as Bates County, Missouri; it is seemingly represented in Iowa by the Cooper Creek limestone and in Illinois by the Lonsdale limestone. Throughout the northern part of the Kansas outcrop area, except where it is locally absent, it is a thin bed of limestone about 0.5 foot thick. In Labette County it varies from slabby to massive limestone and has a maximum known thickness of 3 feet (pl. 4, sec. 143). In northeastern Oklahoma the Norfleet limestone comprises the lower part of the thick Lenapah limestone section. Near Lenapah it is 14 feet thick (pl. 4, sec. 199).
The Norfleet limestone is extremely variable in lithology. It is for the most part identified as limestone immediately below the Perry Farm shale, which has more definite characteristics. In northeastern Oklahoma the Norfleet limestone is light gray, sandy, hard, and massive, and contains few fossils. In Labette County, Kansas, it varies from massive limestone bearing an abundance of Dictyoclostus to slabby crinoidal limestone and slabby limestone containing abundant plant remains (pl. 4, secs. 143 and 159). In Neosho County (pl. 4, sec. 126) it consists locally of interbedded dark-gray sandy limestone and calcareous shale. The Norfleet limestone is seemingly absent from nearly all the outcrop belt in Bourbon County, but it occurs locally there and in Linn County (pl. 4). In its northern known exposures it is characteristically marked by small tubular and irregular limonitic inclusions in dark and purplish-gray limestone.
Perry Farm Shale Member--Jewett, 1941
The Perry Farm shale is the middle member of the Lenapah formation. It includes calcareous fossiliferous shale above the Norfleet limestone and below the Idenbro limestone (Jewett, 1941, p. 339). In general it is characterized by irregular limestone nodules in gray shale, and locally in northeastern Oklahoma it becomes mottled massive limestone. At its upper boundary the Perry Farm shale is somewhat gradational into the overlying Idenbro limestone. The type exposure of the Perry Farm shale is in the NW NE sec. 7, T. 34 S., R. 18 E., Labette County, Kansas. The section there is shown graphically in plate 4, section 169.
Distribution--The Norfleet limestone is only locally present in the northern part of the Lenapah outcrop area in Kansas. However, because of the presence of the bounding limestones and because of its characteristics, the Perry Farm shale generally can be identified along the line of outcrop of the Lenapah formation.
Description--In its Kansas outcrop belt, the Perry Farm shale ranges in thickness from a featheredge to perhaps as much as 20 feet. Locally in Linn and Bourbon counties this member of the Lenapah limestone has not been identified, and at some exposures it seems proper to classify beds next below the Idenbro limestone as belonging to the Nowata shale (pl. 4, secs. 1, 3, 16, 33, 47, 53, and 85). In other places, however, even though the Norfleet limestone is absent, the Perry Farm shale can be identified (pl. 4, secs. 9, 122, and 123).
The Perry Farm shale includes chiefly gray and yellow shale and nodular or concretionary limestone. The limestone is generally light to medium gray and is dense in texture. It occurs in discontinuous nodular lenses. The greatest dimensions of individual limestone masses range from a small fraction of an inch to a few inches. Locally in Neosho County thin beds of limestone continue laterally for at least 50 feet and are probably much more extensive. A short distance south of the Kansas-Oklahoma boundary, concretionary shale of the Perry Farm member grades laterally into limestone which is nodular in appearance and is mottled. The limestone occurring in thin beds in Neosho County is very similar in lithology to the solid limestone in this part of the section in Nowata County, Oklahoma (pl. 4, secs. 199 and 200). Locally in Bourbon County, Kansas, and in eastern Missouri, the Perry Farm shale displays a nearly black shale facies (pl. 4, secs. 92 and 180). In Bates County, Missouri, limestone nodules occur in black shale near the base of the member.
Locally the Perry farm shale is abundantly fossiliferous. In Labette County it carries a mixed coral, molluscan, and brachiopod fauna, a facies fauna similar to that of the Wewoka shale in Oklahoma (Girty, 1915). In Nowata County, Oklahoma, and in neighboring parts of Kansas, Marginifera are extremely abundant in the upper part of the Perry Farm shale.
Idenbro Limestone Member--Jewett, 1941
The Idenbro limestone is the upper and most prominent member of the Lenapah limestone. It is the part of the formation that forms a low escarpment and lies below a somewhat extensive dip slope in Labette and Montgomery counties, Kansas; it is believed to extend far to the north and east where it is correlative with the Exline limestone in Missouri and Iowa. The type exposure of the Idenbro limestone is in the SW sec. 2, T. 32 S., R. 18 E., Labette County, Kansas. The section there is shown graphically in plate 4, section 144.
Distribution--The Idenbro limestone is present across Kansas from Linn to Montgomery counties and has been identified as far south in Oklahoma as the vicinity of Tulsa. It has also been identified in several places in Missouri. The line of outcrop of the Lenapah formation in Kansas is shown in plate 4. The outcrop of the Idenbro member is practically the same.
Description--Measured sections of the Idenbro limestone in Kansas range from about 1 to 7 feet in thickness. It is probable that along the outcrop line in Labette and Montgomery counties the Idenbro is everywhere about 7 feet thick, but the full thickness is seldom seen at outcrops. It is thin and inconspicuous north of Labette County. It forms a low escarpment in places where it is a few feet thick.
The Idenbro limestone is generally light gray. It is commonly nodular, but, as shown on weathered and freshly exposed surfaces, it is not uniform in color and texture. The nodular structure of the Idenbro limestone is less pronounced than that of the limestone facies of the Perry Farm shale, however. The rock is impure limestone. Chemical analyses of some samples show a silica content of 35 percent. The mottled nodular appearance is probably due to its being largely of algal origin.
The Idenbro limestone varies from massive to thin-bedded limestone. Exposure to weathering, however, generally brings out rather thin and irregular bedding. The basal part is more massive than the upper. In the northern part of the Kansas outcrop belt, the Idenbro limestone is more sandy, darker in color, and generally more limonitic than in the southern part. Although it is a thin ledge in Linn and Bourbon counties, the rock is massive, showing no tendency to weather into thin slabs as it does elsewhere. In this facies it is granular, purplish-brown, and contains tubular masses of limonite. The limonite masses are roughly about one-half inch by 2 or 3 inches; the greatest dimension is more or less parallel with the bedding of the rock.
Fossils are somewhat plentiful in the Idenbro limestone. Algal remains, corals, and bryozoans are common. Fossil corals include "Aulopora" and individual cup corals. Chaetetes has not been observed. Brachiopods, including Mesolobus, are rather generally distributed vertically and laterally. Fragments of crinoids, Prismopora, "Fistulipora," and brachiopods, interspersed with algal remains, stand out in relief on weathered slabs of rock in the upper part.
Memorial Shale--Dott, 1936
The Memorial shale formation includes all the Desmoinesian beds in the northern Mid-Continent region above the Lenapah limestone. In Kansas and western Missouri, it embraces shale between the Idenbro limestone and the Hepler sandstone (Jewett, 1941, p. 340). The Hepler sandstone is the basal Missourian deposit of the area. The name Memorial shale is from Memorial Park cemetery near Tulsa, Okla. It was originally described (Dott, 1936) from exposures along the west line of the SW sec. 36, T. 19 N., R. 13 E., Tulsa county, Oklahoma.
Distribution--The Memorial shale is present above the Lenapah limestone in Kansas except locally where it has been removed by pre-Missourian erosion. In a few exposures in Linn County the basal Missourian deposits lie upon the eroded surface of the Lenapah limestone or lower beds. Elsewhere along the line of outcrop of these rocks, a few feet of Memorial shale separates the Lenapah limestone from the Hepler sandstone, which lies next above the post-Desmoinesian disconformity.
Description--In Kansas, the Memorial shale ranges from a featheredge to about 30 feet in thickness. The thickness, however, is generally less. In northeastern Linn County it is locally absent owing to post-Desmoinesian and pre-Missourian erosion. The same conditions have been noted in the subsurface in Miami County where the pre-Missourian disconformity locally is as low stratigraphically as a horizon in the Bandera shale.
In most of its outcrops the Memorial shale consists of well-bedded slightly blocky clay shale. The color is commonly various shades of gray. Greenish and yellowish-grays predominate. Some red shale is present in the lower part in Linn County. Small lenses and stringers of limonite are often seen. In a few places the Memorial shale is slightly sandy but almost nowhere is it so sandy as to be distinguished with difficulty from the overlying Hepler sandstone. Small lenses of brown fine-grained sandstone similar to the Hepler sandstone occur in the upper part of the Memorial shale in southwestern Bourbon County (pl. 4, sec. 76).
A coal bed occupies a position near the base of the Memorial shale in Labette County (pl. 4, secs. 135 and 156). The coal is underlain by about an equal thickness of black shale. In the same vicinity another coal, seemingly very local in lateral extent, lies at the top of the Memorial shale or at the base of the Hepler sandstone. It is impossible to determine whether the disconformity there lies above or below the coal bed (pl. 4, sec. 156).
The Memorial shale is barren of fossils in most of its outcrop area in Kansas. However, corals and brachiopods are abundant in the vicinity of Mound Valley in Labette County. In sections 2 and 11, T. 32 S., R. 18 E., the coral "Trachypora" austini Worthen occurs very abundantly. These corals were actually rock builders there, comprising practically all the rock in a thin zone. The fossils weather freely from the shale. In the same place the coral "Aulopora" is abundant, and the brachiopod Mesolobus ranges upward nearly to the base of the Hepler sandstone.
According to Oakes (Oakes and Jewett, 1943, p. 633), the Memorial shale is absent from most of the outcrop area of Marmaton rocks in northeastern Oklahoma. The pre-Missourian disconformity there is in contact with the Lenapah limestone, a condition that is known only very locally in Kansas. Because the Lenapah limestone and the basal Missourian sandstone, the Hepler sandstone, can be readily traced into Missouri and very probably across the state into Iowa, it follows that the, Memorial shale is present in Missouri (pl. 4, sec. 180). Thick surficial deposits in Missouri cause poor outcrops of these weak rocks that occur a few feet above the more resistant scarp-making Marmaton limestones.
Kansas Geological Survey, Geology
Placed on web Feb. 2, 2010; originally published April 1945.
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