Field Notebook: SD, WY 1956

doc. 0278 1956 UNITED STATES DEPARTMENT OF THE INTERIOR GEOLOGICAL SURVEY — LOOSE-LEAF FIELD NOTEBOOK — 9-137

doc. 0278 doc. 278 CONTENTS. Page [9048] Fox Hills reconnaissance and collecting, July 1956 1 to 15 [7787] Notes for revision Inyon Kova paper Brief notes on Thermop-Cloverly in SW. Wyo. and adj. areas. 16. 17- Fox Hills loc 20 4 to 5 loc 24 5 [loc 21] 4 loc 42 14 loc 43 8 loc 44 1-3

July 11 Lantry Dam locality, Fox Hills here has upper ss member of massive buff frizzle somewhat argill. ss. (Sample) with scattered concretions- loc in zones but not consistent. This in cut of old US 212 to S in cut for spillway lower beds appear. Begin to get more shaly, few concretions but rudiv. large "courzi" This is a finer ss with sh bleks & irreg small lenses transitional with ss above. Is structureless for most part + irreg jointed July 12 Seeman Park locality, Linton N.D. See old notes from Stotler for some of details. loc #4 Around on W side of hill with cut-bank in park is gulley with slopes. Fossil lots as follows. A- From 12veg concs about 2+ above top of "sulphur" zone. Letter here about 3' thick. Concs, shaly, show lamination & thin bedding, same barings. Have huge Gervillias loc. & few zmannitios. B. Loc. concs similar to those in A above. With numerous Gervillia

of moderate size. C. A single small cone in slope about 3' below sulphur zone. Probably not in place. D. Nicolletti concretions in float, coming from just above sulphur zone. E cut bank at Park 25'+ Fox Hills with cones starting loc 3' + yellow sulphur zone Elk Butte member - 50-75 no feet. Large red brown weather Gerilliz cones about 1 foot above base. (3 W's) Change from Elk Butte is sharp here. Top Elk Butte is grey irreg lb ss + sh Sulph str. On top uppermost Sulph. Sharp change to tan ss with, avgill. shale Thin bedded at base, more massive above. Dirty. Nodules "sulphur", prob weather pyrite. Z.

Upper part of Fox Hills not well exposed in Linton area. A platy, grey-white weathering, barren, shaly silt comes in above the basal fossiliferous zone; this has thin glauconitic ss at top, but it is far. quartzitic - chertified, with some red jasper in it. Has fragments fossils incl. ammonites. July 13. (A) Route 12 S.D., road cut just S. of Welpala. This is same one Colton & I visited in 1949. Lower part is light gray weath. sandy sh. with gyp. = Elk Butte? Has some big barren cones. Above, darker gray, also gypsft. with cones. Many have fossils. (zone C) floa of upper fox Hills shwn. weath brownish sandy sh. Zone B berrrn beds above brownish gray yellow sulphur zone? spots + streaks in gray, much selecrite in foschgs gutter barren - grey hard-purple burn stain. sulquartzis cones, getuilliz cones also, with spheria parva< cones - barren to few large geruillis etc. Spotting of "yellow sulphur ends here Zone A large Sandy cones, Soft, frzns. Scaphs rve barren Gray-weather. Nicollctil cones, too weath to collect in float about here 3.

July 13 (B) Road cut thru Trail City member just north(2mi) Little Eagle, Kodzchrome shows fault with Loc.20 T.C. memb down to S. Rough section. Ammonite conc. collected (20aI) - A-266 becoming def grayer Elk Butte yellow sulphur gray Light photo in Bull 27 9r34 conczone some sun, C. 2nd Rd cut in Trail City memb. N. of Little Eagle meq also be slumped TC EB Loc. Bridge Fault Little Eagle [Loc.21] -> Three lots of fossils from here. 3. is from Gervilliz conc. (24cr) (A267) 2. in float just below 1 1. Ammonite conc. (see photos) (A266) 4.

Another zone at top of bluff with large sphenos. South end of cut: Grass roots. Gervillia concs 16 ft slump? zunmonite conc A266 Brownish gry sandy concs some fos. sandy concs between yellow streaks lighter gray grey shale of ELK BUTTE July 19 - Loc. 24 Road to Bullhead. SECOR, Sec. 24 across from house On S. side road Tzecuedia beds in Fox Hills - some spectacular exposures with Holymenites & shell braks. Loc. Bullhead, bluffs N. Bank Grand River just S.W. of village Good section. From Pierre to base TubercLake member. Most zummonites from zone protocordia concs abot 10 or 12' above road. These have mostly fragmental Am., & small sphenos, some Pti nebrass, scott. Gervillia. Zonation of concretions is not clear, but Gervillia concs and Protocordia zummonite concs 5

occur close together, former possibly above. Ammonites in protoceratiz conchs chiefly multinode types, nicolletis are rare. This distrib. needs explanation. July 14—Fort Yates reconnaissance. The Trail City not exposed around Fort Yates. North of town zone large “cannonball” type concretions contain sparse fauna including large sphenodiscus. Relation to Tencrediz-Helymanites zone not determined. General notes on Fox Hills. According to Stevenson no types for either Trail City or Timber Lake members. S.D. Survey practice is to call it T.C. with first sand in shale, 2nd carry it up to first massive sand which is Timber Lake. If these two units are persistent, and they appear to be, then faunal distribution in them is peculiar and needs explanation. Example is Timber Lake member. In Corson Co. has Tencrediz-Helymanites locally – may be restricted to part. Locally some Gardilliz concs?, but 6

no prolific ammonite fauna as at Lantry and vicinity. At Ft Yates apparently some Sphenos et or above local Tenueredia. At Linton only Trail City recognizable, some fragmentary fossils in upper proconsul. Some needed study:- 1. Areal distribution of the prolific Trail City ammonites, sediment study. 2. Faunal distrib & accomp sed; study of Timber Lakes 3. Pickup of T.C. forms to S. and SW. - are they included in Elk Butte memb. S. of Moreau? is Trail City distinct S. of Moreau? 4. Strat. section study from Stoneville - east onto Fox Ridge, NE to Moreau-Grend area, thence up Mo in N.Dak & across Mo. 5. Study of conc. and including matrix at various localities.

July 15. Loc 43 Road cut in massive buff sand N. of Little Eagle (Little Eagle Sand cut) Looks like Lundry Dam lithic type with big & smaller O-B weathering cones, and frizzle sand with fossils. Fossils in sand, Pteriz, Ostrez, Celliste?, In Cones. Pteriz much carbonized wood. collections from cone, & loose Sand. At top of cut is cone layer with Helymenites. Big concretions mushroom & urrey, have helymenites? rare patches clams as in small cones. Loose clams chiefly in lower half of bank road, July 15- More notes on the Bull Head locality. The old road along the river bluff used to be main road. Locally it cut thru the zone fossil Caroc's cones, just above base of Trail City member. and these tossed into river. In face between river and road some can still be seen in piece. Include brrren(?) sandy type cones in yellow-spotted zone, but some float 8

including a large Acantho-like in pieces may come from here. Chief fossiliferous concs are just above spotted zone. Great variety here including 1. Gervilliz type - few Discos, but these chiefly spinose 2. Large concs, pzut broken, with nobs of small concentration and many little sphenos. Also spinose types, but nicolleti's too, the latter not common Some have Protoceratlie dominant. 3. Dense protoceratlie concs. These found in place and are locally well up in fossiliferous zone. 4. Large Gervilliz concs, also have ammonites Completely ammonitic concs - that is dominantly, not found. Gervillizes and Protoceratlie dominate. Some neutilus, rare belemnite frags of phragmo- concs. Bullhead ammonites generally are not complete. Have crushed zones, other fossils pressed into them.

Rough generalized section of Fox Hills at Bull Head Rd cut east Bull Head top of bluff shows alt, ss + sh "banded" Fox Hills, Tenucrediz beds may cap this in flats to east? some fossils in this sand (sand of Little Eagle sandy cut) buff ss red concs. This part barren interbedded ss + sh. few barren cones Fossils, conc. zones - succession obscured Road barren? yellow-spotted basel Trail City contact with Pierre would have to be dug out river Possibility that Tenucrediz beds are topmost Fox Hills ss but needs checking. 10

Possible relations of various collecting localities Linton Route 12 Little Eagle Hillwounds specumulus foss. plume et c. SS upper foss, corncs. ? cover Gervulle cones localument. loc: spotted yellow benever SP upperance zone obscurs) Profserendip Gervilliz corncs yellow spotted Sud sh waggers interan? between? not much yellow content. only loc foss Sulphum Zone yellow spotted nicolletti gerrulla 16t shelly silt beaver Gruec. SS, TIMBER LAKE FOX CANY FOX HILLS PIERRE

Relations collecting localities (cont.) Lentzry Chick. fos. (Bone) Massive ss Fos. concs. O O Sandy sh + sh, l.b. Obscured ? Lentz cut prob. does not get down to the lower fossils, part of Trail City Lucine cons. yellow zone Obscured, loc sandy 2t burs between Bm O O 5s Route 63 on Mortzu Bull Head Fossil lenses concs. Yellow spheroids Sandy sh + Sh, l.b. Barren? TIMBER LAKE I R A I C I T

Notes on sections collected. Timber Lake - appears to become less fossiliferous north of Moreau. Prob, more brackish, as Holymenites comes in - even in canes. Most fossiliferous on Cheyenne-Moreau divide. (Lantry, Eagle Butte) Trail City - Reverse of Timber Lake. Most fossiliferous in Cowson Co. & N.Dak, whereas in Cheyenne-Moreau divide it is apparently grading off into Pierre. This indicates rather definite N-S pattern becoming brackish. TIMBER LAKE TRAIL CITY Cheyenne Moreau Grand Similar ecology, diff age lush near shore marine

July 16 - Rt. 63 reconnaissance. (See Parzde NW sheet for localities) loc42 63A. (kodachromes) road cut in Timber lake? Soft gray sandstone weathers buff, slightly glauconitic (?). Has discontinuous layers febrown conc. ss with Helymenites. In sand are Pteria, discoscaphita frags, and part large sphendiscus. Other evident invertebrates. 63B This is old #135 Elk Butte.- Fox Hills section (Den took kodachrome) Breaks of Moreau in this area (north side) afford chance for working out good section, and faunal succession 63A is above this somewhere smaller very fos, pteria + lucina-like concs. zone big redbrown concretions. observed ss getting shaly flat barren concs. grey bend. loc. concs Sndy Sh. loc. concns yellow band and nodular zone LUCINA & brownish grey SEPHITES also loc. Helymenites. Some nicolletii's down here Grey shaly - first clay shaly 14.

Distribution of various fos. concretions needs to be worked out. All layers should be thoroughly checked because fos. distribution is variable. The upper sandy part with red-brown concretions probably = Lentry Dam structure and obscured zone prob. = the Shelby sand at Lentry Spillway

For revision of Inyan Kara paper 1. Section in Storm Hill quadrangle - should be credited to Mapol. - Not 220, make it approx 170 2. Not enough emphasis on lithic change across disconformity. - Put more in on section on contact and check all sections 3 Check remarks on Fell River channel directions 16

Notes on Cloverly in So. Central Wyoming & Adj. areas Red Buttes area: At road cut on Wyo 220 Mowry - well exposed, considerable soft sh at top. "Muddy" = ledge former Thermop. with black sh. poorly exposed, Some worm-tracked silts. No contact with Cloverly exposed. Further west, near narrows through "Muddy", Cloverly consists almost entirely of ss and cgl ss. In bluffs S of Wyo 220 ancqite; light buff-white woth ss, massive, x-lam, loc. frizzle is at top. It either grades to or is underlain by a massive, harder, conform + cgl ss with chert + qtzte pebbles up to 1"½" diam, commonly inch or a little under. Locally softer clsty layers some white (porcellanite?) clsty near top. Conspicuous absence of "rusty bod" sandstone. Slope above cgl ss shows some floetz of bra ss in 1" ledges but contact itself not exposed anywhere. At best the Plainview equivalent here consists of a single thin ledge or two of hard ss. 17

Rough sketch beds S. of Alcovz, S. of rd across Sw rm extending W Lowest typical Murray Fossil bed in bl/sh Fe s tone This is plshy impure Bl sh, selective thn bctwn them 15+ limmy slt with No fossils + fish remains no ident. spec. found. wssh ss/ B1. Sh. Fissile Fe stone logs calc. westicovered? Shale skprgy SS / calcite ss Cone-in-cone-lirey ? eons Silt, Xlam. shist tip whs some worn crsting. contact sudgy (lwer lb) bl. sh on light granu-lite ss (see kdzachromo E

Sof Alcorn complete section can be pieced from Sundance - Mowry (see if Lovas chzt has it.) Contact is black sudy sh right on top calte ss with no "rusty beds" no evidence leeching. Cloverly is all cgl loc except for thin zone czrk clstn x sh between the 2 cals. Upper is calty Xbedded white sparkly ss, typical Lytle-like. Lower is very good cgl pigeon to chicken egg chert tcptzile pebbles. At Ohio Oil Co. well (Antelope flats G#1) drill in Spring Cr. area, Co. geologists show 3 ss separated by shaly beds in Dakota. (Bob Steed, Casper office, has this report - could probably get it if necessary.) 18

Dakota in hogback between Messidorz and Blue Mt. Chieflly > single ss, cqltc lzyer on top, cqltc in basal part. Nothing but clstn in cuon below but beds immediately under SS are menthod, Lozily lzyer Clf pebble cgl. Mowry SS, cqltc tu wash / vavegatal basal pvt cover claystone South toward Blue Mt. the "Dakota" hogback becomes a double unit. Suspect that at loc. depicted in Sketch the two ss have coalesced. Exposures all along this extensive hogback are good and afford basis for find "two dimensional" study. 19