TWO NEW CRINOIDS FROM LOWER MISSISSIPPIAN ROCKS IN SOUTHEASTERN KENTUCKY BY GEORGE M. EHLERS AND ROBERT V. KESLING Reprinted from JOURNAL OF PALEONTOLOGY Val. 37, No. 5, September, 1963 JOURNALOF PALEONTOLOGY,V. 37, NO. 5, P. 1028-1041, PLS. 133,134, 3 TEXT-FIGS., SEPTEMBER,1963 TWO NEW CRINOIDS FROM L20\'C7ERMISSISSIPPIAN ROCKS IN SOUTHEASTERN KENTUCKY GEORGE M. EHLERS AKD ROBERT V. ICESLING Museum of Paleontology, The University of Michigan .~BsTR.~~T-AII~~~~specimens collected many years ago bl- the senior author and his students near Mill Springs, Kentucky, are a new species of Agaricocrinzis and a new speries of Actino- crinites. Although only one specimen of each is known, it is well preserved. The new Agnrico- crinus bears a resemblance to A. ponderoszts Wood, and the new Actinocriniles to four species described by Miller & Gurley: A. spergenensis, A. botuztosz~s,A. gibsoni, and A. shnronensis. A preliminary survey of species assigned to Agaricocrinz~ssuggests that revision of the genus is overdue. Although the occurrence of the specimens leaves some doubt as to their stratigraphic posi- tion, we conclude that they both probably weathered from the Fort Payne formation and rolled down the slope onto the New Providence, where they were found. The sites where the crinoids were picked up are now deeply inundated by water impounded by the Wolf Creek dam on the Cumberland River. INTRODUCTION onto the New Providence, \$here they were OTH of the new crinoids described here are found. rZt present, both the New Providence B from Lower Mississippian rocks in the valley formation and the I~asalbeds of the Fort Payne of the Cumberland River in Wayne and Russell are underwater at the type locality of the new Counties, Kentucky. They were among numer- Acti~zocrinites. Because parts of the area are no ous fossils collected by the senior author and his longer accessible for collecting, we feel that the students in the 19201s, when the University of description of the new species should not be Michigan conducted its summer field course in delayed any longer, despite the lack of additional geology from Mill Springs, Kentucky. We believe material. these were picked up in 1926. The sites from which the two crinoids were OCCURRENCE obtained has since been inundated by Lake To explain the occurrence of the two crinoids, Cumberland, created when the water of the it is necessary to present a brief summary of the Cumberland River was impounded behind Wolf stratigraphy along this part of the Cumberland Creek dam. As explained below, there is reason to River valley. In 1926, the following formations believe that the specimens weathered from the were exposed in beds of tributary streams, valley Fort Payne formation, and rolled down the slope walls, and nearby uplands (see text-fig. 1): Thickness RiIississippian system (feet) Ste. Genevieve limestone-light gray, oolitic and finegrained limestone layers, fossiliferous.. .... St. Louis limestone--bluish to gray, finegrained to lithographic limestone, 20-foot coarsely crystal- line layer at top, fossiliferous. ........................................................ Warsaw formation-massive, dark gray to bluish-gray, argillaceous to coarsely crystalline lime- stone; bluish-gray laminated chert layers near base; 20-foot gray, thin beddcd Somerset shale unit about 60 feet above base; fossiliferous.. ............................................ Fort Payne formation-gray, coarsely crystalline, and argillaceous limestone with numerous chert layers and geodes; %foot gray shale bed about 25 feet above the base, fossiliferous.. ......... New Providence formation Upper rnember-greenish-gray, soft, laminated calcareous shale, weathering to sticky- clay... some fossils ............................................................................ Beaver Creek oil "sand" member-rather massively bedded impure limestone, cavernous or porous where yielding oil, fossiliferous with crinoid colurnnals. .......................... Lower member-like upper member, fossils scarce; black to dark gray phosphate nodules at base Chattanooga shale-black shale weathering to gray. ....................................... Silurian system Brassfield limestone-gray to brown, massive dolomitic limestone, arenaceous to sandy, weathers to light reddish-gray, fossiliferous with many fluted cystoid colurnnals.. .................... 8-15 Ordovician system Richmond formation-greenish to brownish-gray, interbedded nodular argillaceous limestone and shale layers, bedding thinner and more even in lower half; lower half unfossiliferous, upper half with few fossils ...................................................................... 45-50 CRIMOIDS FRO-If LOTITER ,JfISSISSIPPIA N ROCKS, KENT L7CK Y 1029 El SSte. Genevieve i; ~orsorsow a a Fort Payne L? Nevi Providence - [Gnpl 1Chattanooga -J ~1 Brassfield FAULT & CUMBERLAND SCHOOL FC - Forbush Creek 0 8 - Dry Branch GC - Cub Creek BL - Bee Lick Creek A TEXT-FIG.I-Geologic map of a small area northwest of Mill Springs, Icentucky, measuring four miles on each side. Area includes parts of Pulaski County (northeast corner), Russell County (northwest corner), and Wayne County (so~~thernpart). The encircled dot represents the site where the specimen of Agaricocrinus podagriczrs, n. sp., was picked up. The Cumberland River and its trib~itariesare shown as they were in 1926. At present, Lake Cumberland covers most of the New Providence and all the older formations. Compiled from field map of the senior author, suppleiuented by structure map of Knapp & Twinem (1933, map 51). Nearby, the Middle Silurian Crab Orchard As for Klepser's statement, quoted by Stockdale formation, interbedded greenish shale and green- (1939, p. 55), that south\\-ard from central ish-gray to buH limestone, rests disconformably Kentucky the Chattanooga shale may be as on the Brassfield. young as St. Louis, we believe that Weller et al. Incidentally, the stratigraphic assignment of (1948, p. 165) properly judged it as "untenable" the strata here included in the upper member of because of the presence of fossils of "IVarsal~, the Wen- Providence formation has been ques- Osagean, and possibly Kinderhookian" age in tioned. In his unpublished doctor's thesis (1937), strata above it. Klepser called the Ion-er and Beal-er Creek rnem- As could be seen before the damming of the hers the "Forbush Creek facies" of the Xelv Cumberland River, erosion of the soft lower and Pro\-idence. This n-as later endorsed by Stock- upper members of the Nem Pro~idenceforma- dale (1939, p. 77). Inasmuch as the strata super- tion produced steep esposures below the ledges jacent to the Beaver Creek member are by of the resistant Beal-er Creek member and the lithology, fauna, and age allied to the underl>-ing Fort Pa)-ne formation. On many of the small beds and not to the OX-erljingFort Pal-ne, we tributaries of the Cumberland Rix-er, the soft can see no reason to remo\-e them from the New shales of the Nenr Pro\-idence 11-ere undercut so Pro\-idence formation. Therefore, our interpreta- that the basal Fort Payne chert beds and the tion of stratigraphy follon s that of Butts (1922) Beaver Creek hard limestone capped TI-aterfalls. rather than Klepser (1937) and Stockdale (1939). bIany of these exposures are now belo\\- the sur- 1030 GEORGE M. EHLERS AND ROBERT V. KESLING cz - Species PIOI.. in D.,S;I cup !: a, 1; o21. rn uWPar2 -.me. Awl F~~ula~ 1 "8 8 :; 1 podogricus 315 1 I4 < 1" w, ve~1" ( K 14.3.2 23 1" I obol;;Ion I/1 ; 1, 1 "0.1 314 1 rnedlum convexus (Hall) 1860 ~rofundus orge, > 3. m 1 pity I obou" 1 H~W 1 X 14-22 2 I ponderosus ? / wrioble I modem" height Wood 1909 1 lbOe1 38 1 m d 1 ; o 1 i/ coorsely gionulose nodosus t 1 21(2l 1 2 l/2 x RR 1'"~ I$!%. 1 2/3i?l I <I I ? 1 B 13-2-2 Meek 8 Worthen 1860 1 , , fuguriinus I 4" ~2~$k9e, 1 $2& 1 Y 1 1 / 112 I 415 W. I K 13.2-2 Miller 8 Gurley 1897 1 smoolh illinoisensis smoo~h 1 13 1 51tght1y < RR 1 sar2 / I oc 2121 1 I 112 1 113 1 very low 2.2-2 N8lIer a G~rley1846 1 ti: <I& w I offenuotus Wood 1909 2 / 30 1 ~4 pa,, 1 ;;;: or ;r0;211 1 I ornericonus finely qronulose rnonfgorneryensir Peck 8 Keyte 1938 1 bu//ofus 1 smooth depressed / B 12.2-2 Holl 1858 1 pyramidal crossus smoolh, slightly Clherby 881 1 fuberosus (Troost) 1849 I =Onvex grocilis smooth or finely qron- Meek 8 Worthen I861 1 ~~~~~~o~ffiu~~~el~n~~ plonoconvexus flat, smooth / E,C (2-2-2 Hall 1861 bloiri 1 9 1 qhti> R s lY1 b 1 1 < 1" 1 ~:d;$ 1 C i-l-! i?l sfellolur 1 $ar, 12, "'1 &out I 1 $610 1 hem~spher~col plote~ (Hall) 1858 bei~o~rernus 1 smooth, S~OIIOW 1 24") 1 )I% ser, 1 2 1 :,12 to 1 35 h19h 1 B 2-2.2 iHoll1 1861 infiotus smooth 1 24 ~n1 ~WX aa 1 sa,, I 2 1 12 1 ;; 1 h:gh as wide I B 12-2-2 iHoIl1 1861 orculus qh1 I K lj2.2 lhan 1 Hsubcon8col sornpson~ 1 14 I medium, - RR 1 sar, I P 1 4/5 IVZ I 'bpporently short" ( c 12-2-2 Miller 1894 ( face of Lake Cumberland. IVolf Creek, and other places in the area. At various places along and near the banks of On the other hand, there is no assurance that , the river, the senior author and his students at the new species of Agaricocri7zus came from the the University of Michigan summer camp during Fort Payne formation. Butts (1922, p. 56) listed the 1920's found crinoid specimens loose on the "Agavicocrirzz~sundes. sp. Burlington type" from ., slopes of the loner member of the New Provi- the Beal-er Creek member of the New Provi- dence. Among the species a-ere illlopvosc~llocrinzis dence in a road exposure 1%miles southeast of colzicus Casseday & Lyon and the tm-o new Parnell, Wayne County (about 9 miles south- species described here.
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