Kansas Geological Survey, Open-file Rept. 94-23, page 2 of 4
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Descriptions of Stratigraphic Section

Following are the detailed bed-by-bed descriptions of the stratigraphic interval from the base of the Johnson Shale through the Burr Limestone Member of the Grenola Limestone. The focus of these field descriptions was the characterization of discontinuity surfaces, particularly flooding surfaces and subaerial exposure surfaces. For paleosol profiles, every horizon distinguishable in the field by color or pedogenic structure was described separately.

Paleosol morphology and microfabric are little altered by later diagenesis and are therefore the most reliable environmental indicators. In the field description of paleosols, particular attention was given to the following morphological features:

• Color horizonation (Munsell designations) with pedogenic boundaries;
• Ped structure and cutans (Retallack, 1988);
• Oriented clay fabric (slickensides) and pseudoanticlines;
• Vermicular (root-like) or blotchy mottling;
• Root structures;
• Sesquioxide nodules and coatings; and
• Carbonate nodules and rhizocretions.

Well-developed clay cutans (argillic horizons) are convincing indicators of clay translocation and downward meteoric water movement in the soil profile. Carbonate precipitation within the profile, by contrast, indicates that leaching was insufficient to remove soluble salts due to low rainfall or high evapotranspiration rates. Vertic structures such as pseudoanticlines result from the shrinking and swelling of clays under highly seasonal wet/dry environments.

	Tuttle Creek Reservoir Spillway Stratigraphic Section TS1
	Unit 7	Wackestone Abundant, large, skeletal debris-filled burrows Pyramidellid gastropods and Permorphus bivalves Large gypsum crystal molds Oscillation ripples at top
	Unit 6	Shale (Grayish black N2 to dark gray N3) Fissile Scattered mytiloid bivalves
	Unit 5	Wackestone (Yellowish gray 5Y8/1 to light gray N7) Scattered fine phosphatic debris (bone?) in lower bed Upper bed intensely burrowed and more argillaceous Some large (4 cm diam) mud-filled burrows Algal-coated grains abundant with pyramidellid gastropods and small crinoid ossicles Fossil concentration at top: Productid brachiopods, myalinid bivalves
	Unit 4	Calcareous mudstone (Medium light gray N6) Lower ~8 cm massive and more resistant--graded skeletal lag at base and some horizontal lamination evident Coarse subangwar blocky structure above--probably not pedogenic Abundant skeletal-filled burrows extend down from upper surface filled with crinoid ossicles, pyramidellid gastropods, ostracods, algal-coated grains
	Unit 3	Phosphatic /skeletal lag Angular shell fragments (2-3 mm), bone debris Phosphatic granules and small pebbles--inverse graded and concentrated near the top Large micrite lenses up to 23 cm long and 4 cm thick--some bored
	Unit 2	Shale (Medium gray N5) Fissile shale with fine chondrities-like burrows (light greenish gray) Desiccation cracks extend up to 50cm or more down from top Polygons ~40 cm across with cracks up to 4 cm wide at top Micritic fill (very light gray N8) with clay "mottles" (medium light gray N6)--slickensides on margins of cracks fillings Columnar ped horizon locally preserved immediately overlying desiccation cracks (up to 18 cm thick with columns ~5 cm diam) Very light gray (N8) with medium light gray (N5) clay between peds and in dendritic mottles
	Unit 1	Wackestone (Medium light gray N6) Lenticular layer (up to 4 cm thick) of granule and small pebble-size clasts (including reworked caliche nodules) and bone fragments Highly burrowed--clay-filled burrows and large (2-3 cm diam) granule-filled burrows Fossils include bone, crinoid ossicles, bryozoan fragments, productid brachiopods, pyramidellid gastropods, algal-coated and abraded/corroded bivalves Thin lag of ostracodes and Permorphus bivalves at top

	Tuttle Creek Reservoir Spillway Stratigraphic Section TS2
	Unit 19	Variegated mudstone (Greenish gray 5G6/1) Fine angular blocky peds with clay cutans Abundant large carbonate nodules (some >10 cm diam.)--stacked, platy nodules Granule-size carbonate grains abundant Abundant sheet cracks give bedded appearance Carbonate lenses locally present at top
	Unit 18	Variegated mudstone (Greenish gray 5G6/1) Medium subangular blocky ped structure with fine clay-coated root traces abundant Abundant inclined fracture surfaces forming wedge-shaped peds Pseudoanticlines--wavy upper surface (gilgai relief) Large carbonate nodules (up to 4 cm diam.) isolated and stacked--closely spaced at top giving columnar appearance
	Unit 17	Variegated mudstone (Greenish gray 5G6/1) Fine angular blocky ped structure with clay cutans Abundant stacked nodules giving columnar-like appearance--nodules pinkish gray (5YR8/1) Unit pinches and swells over underlying topography
	Unit 16	Calcareous mudstone Undulatory horizon 30 to 65 cm thick--gilgai relief Extremely well-developed pseudoanticlines with pedogenic slickensides Lower ~25 cm greenish gray (SCY6/1) Medium to coarse subangular blocky peds Abundant greenish gray clay-filled root traces Upper part yellowish gray (5Y8/1) Greenish gray root traces and clay-coated slickensides Top locally capped by breccia with silty mudstone and carbonate clasts. Some breccia layers also present along gilgai surfaces within unit
	Unit 15	Variegated mud stone (Greenish gray 5G6/1) Fine subangular blocky peds Greenish gray clay-filled root traces Carbonate nodules and rhizocretions up to 5 cm diam. Widely scattered high-angle carbonate-filled cracks extend from top
	Unit 14	Variegated mudstone Vertically elongated mottles--Medium gray (N5) to greenish gray (5G5/1) and grayinsh red (10R4/2) Fine to very fine subangular blocky peds with clay cutans Carbonate nodules and large rhizocretions (yellowish gray to pinkish gray)--rhizocretions abundant but with patchy distribution Grayish red root traces in mudstone, greenish gray root traces in carbonate nodules Diffuse but abrupt upper contact
	Unit 13	Variegated mudstone Vertically elongated mottles--Medium gray (N5) to greenish gray (5G5/1) and grayish red (10R4/2) Increase in red coloration upward--upper part appears less clay-rich and siltier Fine subangular blocky peds with well-developed clay cutans Abundant scattered and stacked carbonate nodules (< 1.5 cm diam.) Rhizocretions and large stacked nodules (2-5 cm diam.) patchy Greenish gray (5GY6/1) clay root traces assoc. with nodules Inclined pedogenic slickensided surfaces present
	Unit 12	Micrite/Calcrete (Very pale orange 10YR8/2 Highly irregular--thickness varies from 10 to 45cm Greenish gray clay-filled root traces and fracture coatings increase upward--increasingly brecciated upward Sheet cracks and inclined surfaces with pedogenic slickensides Fenestral fabric and spar-replaced skeletal debris in lower part
	Unit 11	Shaley mudstone (Yellowish gray 5Y8/1) Highly rooted--greenish gray (5GY6/1) root traces
	Unit 10	Variegated mudstone Medium gray (N5) at base to greenish gray (5GY6/1) Medium to coarse subangular blocky peds Clay-coated dendritic traces in upper green part with a few scattered carbonate nodules Ostracods present in green part Evaporite crystal molds in lower gray interval Sharp upper contact
	Unit 9	Siltstone Mottled--reddish brown (10R4/4) and yellowish gray (5Y8/1) Abundant gray fine dendritic mottles and large tubular mottles up to 2 cm diam.--clay-filled root traces Sheet cracks Scattered carbonate nodules (~2 cm diam.) increase in abundance upward--locally form nearly continuous layer at top Sharp irregular upper surface
	Unit 8	Variegated mudstone Upward change from light olive gray (5Y6/1) to light brownish gray (5YR6/1) to pale reddish brown (10R5/4) Abundant gray dendritic mottles in upper reddish brown horizon Coarse subangular blocky peds Some scattered carbonate granules
	Unit 7	Variegated mudstone (Olive gray 5Y4/1) Coarse subangular blocky peds--fine dendritic mottling Abundant carbonate granules increase toward base Scattered small shell fragments Very gradational upper boundary
	Unit 6	Wackestone (Pale yellowish brown 10YR6/2) Lower ~6 cm carbonate beds (1-1.5 cm thick) and shale interbeds Upper 17 cm wackestone with fenestral fabric and spar-filled voids Fine skeletal debris: crinoid ossicles, ostracods, small gastropods, unident. brachiopod and bivalve shell fragments
	Unit 5	Silty calcareous mudstone Lower ~23 cm pale reddish brown (10R5/4) Fine horizontal lamination Finely mottled upper contact with fine pale olive dendritic mottles Upper part pale olive (10Y6/2) Poorly fissile mudstone with platy peds Thin (<5 mm) botryoidal carbonate layers Desiccation cracks (7-15 cm diam.) on upper surface extend down ~10 cm and may be incipient columnar peds
	Unit 4	Silty calcareous mudstone Lower ~9 cm unlaminated (Medium dark gray N4) Medium subangular blocky structure (no cutans apparent) Middle ~6 cm laminated (Dark greenish gray 5GY4/1 and N4) Upper part finely laminated (Pale olive 10Y7/2) Upper few cms gradational in color with overlyijng unit
	Unit 3	Silty calcareous mudstone (light greenish gray 5GY7/1) Fine horizontal lamination Abundant desiccation cracks throughout--polygons 18-25 cm diam. with upturned edges
	Unit 2	Variegated mudstone (Grayish olive 10Y5/2) Relict bedding--brecciated Coarse angular blocky peds--pedogenic shckensides on ped surfaces and clay cutans
	Unit 1	Grainstone Algal-coated ostracods and pyramidellid gastropods Stromatolites on upper surface extend ~15 cm into overlying unit

	Tuttle Creek Reservoir Spillway Stratigraphic Section TS3
	Unit 21	Grainstone Algal-coated ostracods and pyramidellid gastropods Stromatolites on upper surface extend ~15 cm into overlying unit--digitate tops with cavities filled with coated grains
	Unit 20	Wackestone/Packstone Fusulinids especially abundant near bottom Algal-coated grains, ostracods, crinoid ossicles, echinoid spines, and productid brachiopod (?) debris increase in abundance upward
	Unit 19	Wackestone (Yellowish gray 5Y8/1) Fusulinids in upper part Productid brachiopods, fenestrate and ramose bryozoans Large skeletal-debris-filled burrows
	Unit 18	Shale (Olive black 5Y2/1) Fossil poor except for abundant orbiculid brachiopods Calcified shark cartilage found in this unit Upper ~15 cm has abundant Chondrities burrows Thallasinoides burrows filled with skeletal debris Increasing skeletal debris upward--fish teeth and bone, small crinoid ossicles, productid brachiopods (spines)
	Unit 17	Wackestone/Packstone (Medium light gray N6) Bottom ~2.5 cm is micrite with brecciated fabric Sharp, irregular upper surface Intraclastic limestone Angular to rounded micrite clasts throughout bed--become smaller and more rounded upward Increase in skeletal component upward--fusulinids, coated grains, small gastropods, and unident. brachiopod and bivalve debris Pyrite disseminated and as pyritized burrow fills esp near base Black mud-filled burrows at top of bed--Diplocraterion type
	Unit 16	Shale/Mudstone (Medium gray N5 to Light greenish gray 5GY7/1) Bioturbated with destruction of lamination Upper ~15 cm finely brecciated and massive
	Unit 15	Silty shale (Light greenish gray 5GY7/1) Highly bioturbated with fine Chondrites-like burrows Graded silt laminae Gradational upper contact
	Unit 14	Shale (Medium dark gray N4) Graded silt layer at base Abundant Chondrites-like burrows (Light greenish gray 5GY7/1)
	Unit 13	Shale (Dark gray N3 with Light olive gray 5Y6/1 silt laminae) Graded laminae and starved ripples of silt--some bundling of laminae Decrease in silt content upward--laterally continuous graded layers decrease upward in thickness and frequency Very little silt in upper ~17 cm Mostly thin discontinuous graded laminae Fine Chondrites-like burrows locally present at top
	Unit 12	Micrite (Light olive gray 5Y6/1) Lower ~6 cm shaley and horizontally laminated Horizontally bedded unit Some scattered skeletal debris on some bedding planes (crinoid ossicles, unidentified shell debris) Upper ~6 cm gradational with overlying shale
	Unit 11	Mudstone breccia (Very pale orange 10YR8/2) Clasts of calcareous mudstone in mudstone matrix
	Unit 10	Calcareous mudstone Lower ~20 cm very pale orange (10YR8/2) Wedge-shaped peds and pedogenic slickensides Undulatory carbonate layers up to 7 cm thick--A few large concertina root traces present within Silty mudstone above (Greenish gray SCY7/2 to yellowish gray) Coarse subangular blocky peds and curved fracture surfaces More laminated toward top--organic (charcoal?) layers common 5 cm thick massive silty cap at top
	Unit 9	Calcareous mudstone Undulatory interval varies from ~10 to 25 cm thick Mudstone locally present at base (pale yellowish brown 10YR7/2) to yellowish gray SY7/2) with platy to fine subangular blocky peds, and root traces Columnar horizon (yellowish gray 5Y8/1) Well-developed columnar ped structure with 4-5 cm diam. columns Abundant root molds and concertina root traces
	Unit 8	Variegated mudstone Undulatory carbonate horizons at top and bottom of interval Yellowish gray (5Y8/2)--abundant concertina root traces Incipient columnar structure locally developed Mudstone (Pale greenish yellow 10Y7/2) Fine subangular blocky peds with clay cutans Manganese coatings on high angle fractures and ped surfaces
	Unit 7	Variegated mudstone Yellowish gray (5Y7/2) changing upward to pale olive (10Y6/2) Well-developed clay cutans and clay-filled root traces Manganese coatings on joint surfaces and along high-angle fractures, also dusky yellow (SY6/4) staining
	Unit 6	Silty micrite (Yellowish gray 5Y8/1) Manganese coatings along joint planes and curved fractures--also manganese-coated slickensided surfaces Apparant mud-fiued solution cavities--boxwork developed within some large cavities Upper part is conclomerate with rounded micrite clasts up to 13 cm in diam. (pale yellowish brown)
	Unit 5	Silty micrite (Light brownish gray 5YR7/1 to yellowish gray 5Y8/1) Horizontally bedded (2-5 cm) and laminated Manganese coatings on bedding planes and vertical fractures
	Unit 4	Calcareous mudstone Lower ~18 cm soft silty shale (yellowish gray SY7/2) Shale truncated by irregular, rubbly carbonate layer with abundant celestite throughout (Yellowish gray 5Y8/1)--Overlain by collapse breccia with silty carbonate clasts in chalky matrix Very sharp planar upper contact
	Unit 3	Calcareous silty mudstone (Yellowish gray 5Y7/2) Lower part with coarse angular blocky structure Hard cap of varying thickness--wavy upper surface Closely-spaced lamina of fibrous celestite (?)--botryoidal surfaces and inclined surfaces with fibrous coatings Some overlapping crusts (tepee-like strudures)
	Unit 2	Very calcareous silty mudstone Lower ~10 cm greenish gray (SGY6/1) mudstone Coarse subangular clocky structure and light dendritic mottles Upper part yellowish gray (5Y7/2) Closely-spaced thin botryoidal layers of celestite (?) and abundant small nodular masses
	Unit 1	Vuggy limestone Pale yellowish brown (10YR7/2) to dark yellowish orange (10YR6/6) Celestite-filled vugs abundant--merge into nearly continuous mass in middle part of interval Horizontal to wavy bedding at top and bottom--oscillation ripples locally well displayed in upper ~10 cm

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