Hsi A Comparison of the La a Maquoketa Formation and its Fauna in ¥ Eastern Wisconsin, lowa and Illinois us | ACS ria Vea WOW TLIEN GIS IIR ABST +! we aay “a 4 + ¢ ait . My 5. ae fi : a f ' ¥ oe ‘age - y a 8) % ‘ . By a : SiS ois a Ay ." ‘ if *," “| .* ahs may A ale ,. \ ae Ss is Shy ah rede. \ wee Py, oe ete, * 3 Oe. a 6 Pa MT Ue Na 7 Be ae PA est Ae RN EG oS SA NTE Qa) Bee nd NS tt , ba * = +s * y Ny on) : in wi. ey ! + Peed eae eo ae S - ee am ald a ae 2 os CY Me oe 4 : , POD an a a A. Sa =P — 2 Ge, ee, hy odes pee Feo ae ms Br . at * 9 td eae > Pa er Ww *y . i oe A 2 ot Bg oP _ Sa) Wee Sy . = z Oo sy TOG HoH << nA Sea & - Or. ef ie ‘ss Ass: . . fe Sei . - 4 % ‘ my” at 4 fe . “i: i . * A (D. « WRAGN Be PES. 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Re bea TAN i SSG ae + . “Holt @ TASH VGSILIOSM ART: Bey Cores ALY SALLE, Ae Sita hi Sila sf t poe th tiecariccestt 7 Wy tt Sotiris) a. ” a ‘ooltoedaaek Lett: ay y CONTENTS. Maquoketa in Wisconsin Location and area | Physiography of the Maquoketa area Previous geological work on the Maquoketa , Bp tierephy 4 Detailed sections and fossil lists Maquoketa in Fastern Iowa ‘Location and area Stratigraphic relations of Maquoketa formation - in Iowa General section of the Maquoketa Fossils of the Maquoketa in Iowa —* in Illinois Location and area Rarlier geological ave on the Maquoketa in ‘ Illinois Detailed sections and fossil lists arative table of fossils ribution of species and its significance 848958 <= he 29th efaxoune! ems Lo. Nahe oud OFS mo xcow Sap lyase wigh ave8i fIiece’) (be soortsee Sa liae \ awol ireteoi Mime B9'ré bre i > LU * 7 4 N70 etodolpal To Baeses fez bietue cm, r anol in SS ci oupsil eit “to moticee Latent 4 7 ‘ Jt AWOL ii SP pLpae. ahd to #fteag eh toni itt ob ets B9Te be 7 e s atctoupe, sity no: A0w insisetoea! *4 a ee tr are ht itesot ins awttogn & . ‘ 4 pag wee attaae’ ay $3 fa LIST OF ILLUSTRATIONS. View of odlitic iron ore at Cascade Falls, 4 miles east of DePere, Wis. View of odlitic iron ore at Neda, Wis. View of the dolomitic phase of the Middle _ Maquoketa at Clermont, Iowa Lower Maquoketa peas, at Elgin, Iowa View showing characteristic Maquoketa topography * ‘ - a View of upper beds of Maquoketa at Millsdale, Will County, Illinois Wis ereguoketa shale in Will County, Illinois | pee prez Creek shale, two and one-half miles north of Thebes, Illinois ‘View of Thebes sandstone, one-fourth mile _ south of Gale _ Map showing areas of land and sea in North America during Richmond time as = , ad \ nigpagerpty Slint: basset se ‘e208 | “ehh preset? at@ .2do, ta ete nous a ! i a fboiz eri t te cle Oe, inte Lob : ant tole £9: ‘oe evel jiy tk ey eee at ioupale HIER ghiwore: ‘ead ee Steteiliz te sreaocugeL ro anea "3 sonst ts ere siogifar sind SIL nt whale ete eeiiw tids=wio baw sien vate ie Seed wp ntes LIT. tex fax £O. re shotahase osteee” xe . alet: td sneelee £ — ! 7 J ite) U2 Aad: P rubles 6 Anet® sikwohs ami Rockl>in , aaa Gotaaat INTRODUCTION. The name MAQUOKETA Shale was first applied to this form- fation by C. A. White from the Little Maquoketa River in Dubuque } county, Iowa, because this formation was well developed in that } LO@cality. The beds at first were considered to be equivalent to the | Hudson River Shale of the State of New York; but Meek and Worthen showed that those shales in Iowa and Illinois are not equivalent to the Hudson River Shale in New York, so the name Hudson River | group, as applied to this formation, was dropped and the name Cincinnati group was proposed, because the principal formations Of this group or series are well exposed in the vicinity of Cin- | cinnati, Ohio. The Maquoketa Shale is now known to be equivalent tO Only the Richmond or uppermost formation of the Cincinnati, for only the latter formation contains fossils similar to those which occur in the Maquoketa strata of Iowa and Illinois. In 1870, Mr. C. A. White, then Iowa State Geologist of Iowa,was not satisfied with the name Cincinnati grounv for the strata under consideration, and he proposed the name Maquoketa Shale to designate this particular formation in Iowa and northern Tllinois. This name today is well known among the geologists in || this country, for the rocks in the upper Mississippi Valley that represent about the same time as the Richmond stage of Indiana and Ohio, but which were deposited in a sea that advanced into this area from the north or Arctic regions. The Maquoketa formation if tel Lege oats ae eRe te im 7 Sree Ae At! il ‘on SWE aN SRO Brea Sol Eon) eee eX t of tx Ae ofevel. [low exw. cod hace eee Sekeoal a ioavinos 8d of betehfasos Oren iReaee fe show dao Jpd ite? wet 6 seeds sire oo otedt | . atl oft ina Baggot, ake ne bee eet ot Sobd yitousot Lidisaizg efé eenaaee Gueegese er oval .. Ito ic. Voanioly sm pe “beegere {fou ope soltos cd 3 tiro9 ad of epemacsl wine ee iif i Sg Sk onndal a iO. 3, he hedtaertat Seuarth yaa A ‘Byeqncse 14 wri 2089 of Setinie @iisssteniernae: ‘no Ltpacol vata LON OLE tae ewok et Hands etqderipett 3 (okt “users VES a hont> eiaa an stay ba sagiiees ll na atone Ben Yan ic ables iar beat woud u as ‘odsrinnas tio Hie f 525 SHS> “Wo - at enh ong ype “tered L bow at sof Tey iqqiagies he jitd Josue en saat nee, a, ips occurs in Wisconsin, Minnesota, Iowa and Illinois, as is shown by he similarity of its fossils in these areas. The Maquoketa in Wisconsin. Location and Area of Occurrence. The Maquoketa formation underlies a considerable area in HSoutheastern Wisconsin, but it outcrops only over a narrow belt, extending in a nearly north and south direction from Walworth to Lake Winnebago, and thence northeast from Lake Winnebago to Sturgem Bay. The width varies in different places along this long, narrow Jbelt, being two and one-half miles at Walworth, five miles near ero xa. one mile east of Lake Winnebago, and one and one-half jmiles south of Green Bay. From Green Bay to Sturgeon Bay the jwidth is only about one-quarter of a mile. Physiography of the Maquoketa Area in Wisconsin. Bordering the east side of the Maquoketa area in Wis- listeep Slope on the west side and gentle slope on the east. The lexplanation of this feature is that the eastward dipping Silurian limestone overlies the Maquoketa Shale, the shales and clays are soft and easily eroded, and when the ice sheets moved over this region they eroded much more deeply the area over which the | Maquoketa Shale formed the surface material than the area farther east where the surface material was underlain by the hard Silurian }limestone. Since the Pleistocene period the many springs that issw at the top of the Maquoketa Shale, and the general agencies of tia “ab eho wae LT IV? te Supt Mare 3s =: ato al sae Beat: a OE ee: ae pe, eet «2 Dags eget gee ip. 2.956 Gai as dé J mateo, Be sdavpan a LS, oo be ae A 2 ¥O ¥liho raqotasoeoyg ied ndepooalt , Peer ( & Bit ‘noe, ¥itmen 6 aay fet Es Es fa $3 pec eo : 2Opart frat 52% ig iad aopTR wevela tuamehti ie yorsay deg if .ctow few is. ae fia ‘Ped ae bane | ao Dee ,omededaiy ota ke tees ot iat 1D Yee sete eda: Cal Naete ay iS oth SN OS Bat So solos ar ni —— : O°. Soa uns to sbta sued "52: Po sotoswE feta ie 25 ees Aieaiaite, itn adds ee pers i Sin sbhdH, sem sit poe ae ra ras uri A EGE SAW GS) ashe -| tata et — toe % x "7 wit Mo id poy aes ana J Loneh P pm nts utes eit pate BY. iat aoe? agi Se : ie ere ae ais Bobi aA teks ' ig ttige ‘cae oR co albaaa sawpsdabe a = ahaa canbe pita: (ee pega | weathering, have still farther eroded this formation, in many places undermining the overlying limestone, huge blocks of which have fallen or crept down from above and have come to rest on the more gentle slope near the foot of the cliff. The Maquoketa strata outcrop in the bed and banks of many of the streams between Green Bay and Lake Winnebago. The best localities in Wisconsin from which collections of Maquoketa fossils were made are Cascade Falls, about four and one-half miles east of De Pere, and along a stream east of Green Bay, The beautiful Cascade Falls occurs along the channel of a stream which is very shallow above the falls where the water flows on the Silurian limestone, while telow the falls the stream has cut a gorge through the limestone and o§litic iron ore bed into the soft underlying Maquoketa Shale. At the exposure east of Green Bay, there is formed a succession of rapids where the water runs over the limestone and greenish blue shales. In 1862, James Hall and others made a reconnaissance Survey of this region and referred to the Maquoketa and overlying Silurian limestone in eastern Wisconsin under the name of "Green and Blue Shales and Limestones". They described these strata as extending from southern Wisconsin to Little Sturgeon Fay. This revort did not give much detail concerning the formations. Geological Survey of Wis., Vol.l, pp.170-17". nh bia Hiets “Bohne vadaae, cag Sno voted : gmikdtbeo ent he, Fae: i oo S788 ‘RNs vale mort nwobl ge * tied i} VF 60% eae ey a iy uf ceeado- wet fe ae eee ina bia . 7 . ped Listat ] Be yee | : 95h jin fiw. stot AE ootam abs useWede mtg 4 10 AAAS, NOGA” | 4 2 SASGkeg a8 3s Vial | ROSS BS yr A grote ba fines mono site oant Bes WUT Lek, etS evens wo! fede let sh? woled efine | 2doreeee ona Wye Sitydeowk tl wee Sieh uy eo tade pi as oly RiNet To: 6 BRS9ON9, ‘nehuoee as eek , me ) a t "7 axfeot sated de kteeny Sou epee “ j bat. tigress? ooeiae estes pits, Lk Sate, geet, hae a4 = Ley.9s bia ehex aap ity OF herteret Orig nog ea bids t he gina Malte cet AL oboe Ee ntodegs el ae ig ; ais: Boi i ig: a BY Ven a" i 29 : ta Geant Bed i ie sonos dlgakdh Bika bs 99 Lage "ey ie +e ii eae e 9 List ad atau ere Fors ie ce - NVE~Ot Le Bho cae to earent test ¢ ‘ View of bed of oB8litic iron ore, near middle of the picture, overlain by Silurian limestone, and underlain by Maguoketa §hale, exposed at Cascade Falls, 4 miles east of DePere, Wisconsin. fe £675=1877, T. C. Chamberlin,? the State Geologist of ‘jj Wisconsin, made a careful study of the Maquoketa strata near the town of Eagle, on the south side of Pewaukee Lake; near Hartford and Iron Ridge, and in the vicinity of Green Bay. e Chamberlin published the following gener- In his report al section which gives a clear idea of the Maguoketa Shale: 1. Hard, fine grained, compact, argillaceous Fee oamessone, in beds 10 inches:in thickness- - 9 Similar, but harder limestone, marked with contrasted lamination, some clay layers interstratified - bluish~gray in color- Shales varying in color and texture- - Thick bedded, blue,cherty limestone, with some impurities in the form of partings- Very similar to the above, but harder- - Thin bedded, broken, irregular, cherty, calcareous layers- - - - - = In this same report Mr. M. Strong; who had made a study of the strata in the lead region in southwestern Wiseonsin® des- | cribed the relation of the lead formations to the Maquoketa. Stratigraphy. The Maquoketa formation lies between the Galena lime- Stone below and the Silurian limestone above. The Galena limestone || is @ yellowish-brown dolomite, between the layers of which are |) shaly leaves and partings which have bluish and greenish color. lL Geological Survey of Wis., Vol. 2, pp. 314-326 au Geological Survey of Wis., Vol. 2, pp. 319. 1877. S Geological Survey of Wis., Vol. 2, pp. 685-688 rFdweesry si th bia 4a +4 ry ane god settnast ob he ities ene a0 doz : o oben) afte. 3 pele hs FIRS ws linet besarte nee - Do fi Leer cewevae . | ——— ia oy tle tite? 2s iegee a > - s ¢ ss < » LY: So8bed oie ig ees Ss t il we sPicugul oaggaee ik” od te LL ta vrete ‘ reaxtota, . heise cyte +S25¥HE avout cote 4 “ = > 2 : ; : a = fTHtos. shee ARP Fi seed a ra eee This formation unconformably underlies the Maquoketa Shale. ) In some places a bed of iron ore immediately overlies ithe Maquoketa ghales and in other places limestone of Silurian age rests directly upon them. Fxposures where the iron ore separates the shale below and the Silurian limestone above can be seen near Mayville and at Cascade Falls. At Mayville there is about 30 feet Of o§litic iron ore which is overlaid by about 20 feet of Silurian imestone. Below the iron ore is the Maquoketa Shale, the thick- humber of characteristic Maquoketa fossils were found in the more SBhaly bands in the lower part of the iron ore. It is thought that these fossils indicate the Maquoketa age of the bed of oB8litic iron Certain horizons of the Maquoketa Shales are very fossiliferous but some of the species that are present in one place are often absent in another. An illustration of the above state- jon the east side of Lake Winnebago, and in exposures four miles yeast of Green Bay and four and one-half miles east of DePere, are Jabsent in the shale near the town of Gardner, about twenty miles yrest of Sturgeon Bay. The masses of shale exposed along the foot of the cliff near the edge of the water at Green Bay show beautiful Iripple marked surfaces. The thickness of the shale auc dea above the level of the water is at least 100 feet, above which is a v cea am. 7 ' a i . v) oy tA Ge Ar ae} > a = a ert ean eet Oe ec | Ny gees | Lae sferorgat. oud ee z ) a te a mt > Oe Ae 5 aod iy pe ir . ap: a ee a ty j les hg Bas sere ived- ie) eae x9 reas rofd sil Te tear eis iotltyw To eons int- ame =| } then bapotlsiew alisag. ae ¥ ‘och me ilsool aiay ee Bette »F . p { LLY Fe ry Bi Pie” | GOK PSHeUs : j } ee Mage t iff sad jute) abaya lat | ' 7 ~ . “ - > vr ¥a De ih ve - - “ai 2a i #3 Tae “HOO” ,aSisMgert anstaomes E-t7e ei . 4 “BLOT % = Pah = ruaad. wines yb if ‘atwottoy cine ees re a wenore + Ps i ~ “ “Uatg ns Bs. _ + J ° N 7 a bitiet nod. ets 4) ‘es abxke aQe feet. The brick company uses the shale from number one and three of the section in the manufacture of brick which appears to be of excellent quality. Fossils from Number 2 of the Brickyard Section. Glyptocrinus stems Rafinesquina alternata Strophomena wisconsensis Hebertella occidentalis Byssonychia radiata Cyclonema sp- Fossils from Numbers 5 and 6 of the Brickyard Section. Streptelasma rusticum Plectambonites sericea Dalmanella testudinaria | | | | Hebertella insculpta Hebertella occidentalis | Platystrophia acutilirata | Rhynchotrema ainslei Rhynchotrema anticostiensis Rhynchotrema capax > / Homoeospira sp. The above lists show the difference in the fossils in | the lower and upper beds of the Maquoketa in this locality. The genera Strophomena and Rafinesquina are common in the lower beds + ft witope f astot + tat sits xe = “sip climes alg . assje avatroot@eny 4 KAT ot Le whlupesnvnen } a etencancoelw oan 45 iodqgott? ei fadastiaso 2 ileJued@e | aieibert aigovmasva ie, sane Lor Cae / : a ay, - rs e + 3 Oi7290 biavyaoizd af? Yo 8 bea © .esed sf i ootr sits O%, | ee. to eee mE ai ee ee aa muoiteua Seesfotgarde ssoltoes cae Inodianad cal Ltenibuvont aL sweat , Big liter’ a1 Letras gli vee) ec atistuebtene pLisdsed sw? J ae asaei Ligaen aeesiae sink a ni Leauge ole we =10- (and Rhynchotrema and Platystrophia are more common in the upper, } and Hebertella occidentalis is common both in the upper and lower beds. Section of Maquoketa strata four and one-half miles east of DePere, exposed in the bottom of the creek for a distance of one mile. 5. Alternating layers of hard and soft limestone, 4 to 6 inches thick- - 4. Alternating layers of shale and lime- stone- = - - - = = - 5. Shale, impure- - - - - 2. Limestone, very soft and shaly- 1. Limestone, hard, shaly- - - - = = The following fossils were obtained from the Maquoketa strata at this place: Streptelasma rusticum Rafinesquina alternata Strophomena wisconsensis Dalmanella testudinaria Dinorthis subquadrata Hebertella insculota Platystrophia acutil wata Rhynchotrema capax Rhynchotrema inaegquivalvis Orthoceras sp. An outcrop of Maquoketa strata, nearly one-half mile | lone, occurs about four miles east of Green Bay... The total thick- | ness here exposed is about 30 feet. The upper part of the section act aihooudette bess * he oer ek pees ari ihn: ot at nee ~~“) 6 j Luo tb Soe atovounelr to sare pant 3 At Des ouxe a teFed. 0 tease” rofio, ‘ioe aan >.ofim gmc bo. s8hess ib 2 Soh ee eonee ROMs Rs r aS ) aa sie & en oF LA. ‘ «var } ‘ , Sea esings + - d fi - Ma ' be bet att we oe ; a “4 “ “ ~ “ - ~ om rHCwE aS rt ‘ wt i fi me. yrs ) 4 , + . ote SS Lg ; f be * S 4 2 % - ov = e* . gehts mi fe nted fe Prisons srl see * — Zz ie en els Oe bh “ : iM sso poniv Atengngotsa L1H LAR RSs al fenne Leg ae vit htorbewpdue a detog be aa ; : erations: al anand LY is ant 17 bets) (foe tidied pe ee “afi anents bas KEY Les ipsam “om i eta a bo 4 7 ; men 0 “ce 4 “f raf ‘Ra ir : ra olin, Yet emee thease: at tiie : ea AOS Je r. gut” sai teaie me ies +s ek a ee ne a a a. ay ye oe ee at this place corresponds to the lower part of that east of DePere. The rocks here furnished the following fossils: Rafinesquina alternata Plectambonites sericea Strovhomena neglecta Hebertella occidentalis Platystrophia acutilirata Plectorthis whitfieldi Rhynchotrema anticostiensis Rhynchotrema capax Pterinea demissa The following section is exposed at Cascade Falls, four and one-half miles east of DePere: Feet 3. Silurian limestone- - - = - = 350 2. Ob68litic iron ore, with shaly pebbles and a thin shaly band in the lower part, containing Maquoketa fossils=- - Hard, calcareous shale, in layers up to 14 inches in thickness, without fossils- - - - - - - -10 The following fossils were collected from the iron ore bed at Cascade Falls: Cf Stenaster sp- Strophomena wisconsensis Dalmanella tersa 0 Byssaychia radiata Pterinea demissa Cf Liosvira nucula “On hy = i. : tA ay ae ort uadt ork heros 19% stow aaa wa s stele det taodusduete . r +, fob te VSL sisaediyeHee ? LF :$HOII00 » ‘tedvedbe Siedgt £idives tkinotwieuie Eten bd zole tedcotod bee Srensiseooli ms SeHtye onrettt > caso ‘ames rounieuh Ee salnusb Lsitilwed?e Cre? shaogs ta Bbepegias ss neltged af wollos ‘ur i ai ;sreied t gate welgn K Lact . Co en ES ea Cae an lid ey op hans ibd ' eho get SS PER, | * A] Af = Sto : he Mississippi River and along the valley of Morts Creek in Prairie Spring and Tete des Mort townships. The Maquoketa has a wide distribution in Clayton County, forming the surface rock of the uplands in Jefferson, Volga, Read, arnaville, Wagner, Farmersburg, Marion, and Grand Meadow townships In Fayette County the Maquoketa covers nearly the whole area north of Turkey River, outcropping in the bed of Otter Creek rom one to one and one-half miles east and one-half mile south of est Union, to the junction of this creek with the Turkey River. [he Maquoketa Shale also fringes the channel of the Little Turkey River from Auburn Mills to Eldorado. The Maguoketa shales occur in a large, irregular area south of the Upper Iowa River in Winneshiek County, covering parts pr four townships south of the line through the northern part of Borinefield and Frankville, and extending from the valley of the Purkey River to the line between Winneshiek and Howard counties. | | | Previous Geological Work on the Maquoketa in Iowa. Clinton County: - The general characters of the Maquoketa 1 and James Hall”. formation were described in 1858 by J. D. Whitney Miter this, W.J. McGee made extensive observations on this forma- ion and published an account of his work in the Pleistocene [History of Northeastern Iowa. In 1905 J. A. Udden* made a detailed Geology of Iowa, Vol.1, pp. 278-282 Geology of Iowa, Vol. 1, pp. 70-71 llth Annual Report U. S. Geol. Surv. Part l. Iowa Geol. Survey, Vol. 15, p. 373 bp iarts Tigaatth aw) Chali ae ‘a! bie Towa 'e favor | ost? " iy" bean hy atid vi. Cet - sd * LL okt eh pee Bee ie nex oan it aokd a) ee eh 2a8 spades awe bya i : a} ia ts) Pe an FI : my) yr = 4) ie : 7 alt ayy) ey’ Gee res. Lat Ct bio, Dis bite, “ev bd cela abd ya ashi “a ‘oD: Sa as Smeal tote F j wtinCetakte 7,7 a All * » Dag ; gua oi P.' got ’ ESfi + AD) ise rf , 4 rt 7, id ; LA ioe z oL8 ‘ 5 aefite oF nq idee {uanoin? enti any Lelio ="! se rit Ete A 9 -19- 8. Bed of fine-grained, impure limestone, in even layers 6 to 10 inches thick, consisting largely of chert nodules or of chert bands segregated along the planes of bedding; containing large individuals of Rafinesquina alternata, Strophomena.incurvata, Dalmanella testudinaria, Hebertella insculpta, Rhynchotrema capax- - - - - Massive bed of yellow, fine-grained dolomite, containing a number of chert nodules, and bearing Lingula iowensis and Orthoceras spo- ~ - - - - Lower Maquoketa Division. Bed of bluish; plastic, rather fine- grained shale; in places containing numerous fossils among them Rafines- quina alternata, R. minnesotensis, Plectambonites sericea, Strophomena incurvata, Dalmanella testudinaria, and Rhynchotrema capax- - - = Bed of lean, yellowish-gray shale, in places somewhat arenaceous; containing in the lower part, thin bands of impure limestone, 3 to 6 inches thick, and con- taining Stroohomena planumbona, Dinorthis subquadrata, Hebertella insculpta, and Pleectorthis whitfieldi- - - - - 10-13 Bed composed of layers of yellowish-gray shale, 3 to 6 inches thick, separated by bands of impure limestone about @€qual in thickness to the seams of shale, becoming more calcareous below; bearing numerous nodules of chert, and contain- ing Plectambonites sericea, Hebertella insculpta, Rhynchotrema inaequivalvis, Hormotoma gracilis, Pterygometopus callicephalus, Cerdurus pleurexanthemus- o.- Nileus vigilans zone: consisting of a bed of gray colored limestone in layers l to 4 inches thick, which are separated from one another by thin bands of gray shale; containing Nileus vigilans, Calymene senaria, and Pterygometonous callicephalus- - - - - - - ~~ nto Tess ey hie hen tae lotee pecoke Cia eceam ar cee Sfphor Jens ts YLepss. pedis Se ye Tobe Sheed rears ty; 32. (grekbhhad; ze ‘ WwLS5 33 his ued 1 Sa to & Se abEN ‘ss t le A / oh. ae rh we 3 a ae TTUSAS i Swistrede F< ae é ‘* i —KOOLD higergiy eh ites | rox te hed oo . Sie pave! Re meet nce) y out elanavcl S-Leterigerneaiiesd sige 8 SLb om ’ + AMMERSUEY OF ILLAIGIS Gp Baty eae gt SA PEER RL EEE SRB. EO . -onl) tote | Sitaate bsibio f4 <9 et utiniatnoosesbeaty Re ie ieite fornia’ “BO iBR nent Sete AebOaee aia cont 4 ,Ulsisioasitim 7 4 steared be eas ee MonCNYOt+eS ASSITEG eetinodnpey sole “Afisnibutged sl lonigis® - staves Lm m~ aa - > SAGES FURS ES Ost canst falas ial i nt) eLadeege ‘ouReatan soak ipibe aiinivings «: sioecgeres fariwonom seoale osNvqmi- “to bbhbeed- weg Pe 72) | TOW OL. ‘ont nh “70s he YoIny Reno ne f oFf-e Srto*eomi lt eur huio ecsmodeét de” ante tes i flieiredst sfurbavpdiee {- - - ~fhledtrbow sins regeatt - off[oy be atavel: te (bat ouitge Ban see . 1 ASICs aahom & OF ©. ce Beate ‘ roc gnvuscami } orem: Te: shred a falas »o Seen BGs ie veld ad SS Ree Bee TS eee 6 nd ywolod etogiiko [do saoke gimme ely etm -iteinds bas i2edgetoe ee. leben eigamame. elisiradsi .«sy lee 859 Dyotigat oe aay : Vievivosstar cae erononian weqteouat . Sktetwiogy tae etl oe te amo geo Cosa ~p| monks er setiele. epi. (at andar EL fo a. | dB MW Gnite Lengo. rox ait Shyte sitesi a f stoyal ne’ sweteonl tl Soro Loe. vires TS ots 5 re Th Ge, 0 Be. ‘ie bry ey Mp ty + “eorton? ot - YOty To Seiad NENs ee Tety ots 30 oti * aan LORBLIS EY phate ee - on : : Felt og DB A SS of ILE... Shuman A. aaaiant ayy een. 4 - - ~ - —e. ~ Se ae oe ans ee ee 4 8 ke tie -20- Figure IV. View showing exposure of Lower Maquoketa beds, Elgin shaly limestone, in the south bank of Otter Creek, in Elgin, Iowa. J oa es ee LIBRARY ; oA . . OFTHE. ~ ne: we = we UNIVERSITY OF LAIGES ‘ \ \e ; f 7 2 - ; i . fe : to ce [bn of NouSEM ewe To shiyadqaiel Sedegie were jon TAtd 0. ae Seas SS boa ahd. pe PRs Raitt fet ‘ 1‘ i r : 4 iy « a 7 be )' } e f e J ta% Ys 4 ‘ we r ‘| ed Ow) al is = ‘< . ‘ ‘ et) : 7 i a ba) Cee A Bae fh - el Lin Sie SR ee ee” Bie ee ‘a Bed of bluish shale, usually dry and indurated, in layers 2 or 3 inches thick, between which thin bands of limestone are intercalated; among the fossils are Lophospira quadrisulcata, and Orthoceras bilineatum- - - - - - Isotelus maximus zone: composed of layers of bluish; fine-grained, argillaceous limestone 4 to 8 inches thick, alternating with bands of bluish-gray shale- - - - - Fossils of the Maquoketa Shale in Iowa, __Exclusive of bryozoa. Astylospongia ? sp. # Hindia parva Ulrich # Streptelasma corniculum Hall * @ # Streptelasm sp. # Lingula iowensis Owen g# Crania sp.* Rafinesquina alternata Conrad * J# Rafinesquina minnesotensis Winchell* S# Leptaena unicostata Meek & Worthen * # Plectambonites sericea Sowerby * g # Strophomena planumbona Hall # Strophomena fluctuosa Billings # Strophomena incurvata Shepard @ # Strophomena trilobata Owen * Strophomena sp. # pd aoe ¥ ~ i AE Bears & 2.4% ; ; Oh ) a S *o mae Ben ihe 4 aint 2s reer Re a ae otis ase ond. A -boselooredae ats scedsenke to hein 59 a, srickoscel ste gifesel sid /gnome a asvopot?=). BAB T, Rieoleebthege oe : ; ~~: ES maudeant iid on ¥ to benoghed seitas ai ent xe ois Habana Senigty=sied (alk Te! aia Hog 2 Sito ae mit LoLl Fiese: aad dd¢iw apnivenies Le: 3 iota essoae @ i » fm A Ls ie ene } > a a - - - * “Sintia .vota-neatyia Fae aE si fade atiestouwseh say Tq —_—a pare boevierareet ee owes LP SY PACD S | rosie manic | ‘ % °@2.? pbgnogs aie teA Ps hae yo eal SVT aiden % & * Fish - weit teres ance Lodgexta” eae 5 ‘7a ussies qe1ses fy eR £12 0 ~ sinnewol ‘olin chk; % 18 Pree up s “7 Sethou . ete ares f fz cgi eae Ay —" ay. * Lars ates : ‘etadndnaedian eth Psp a 4 ceridre® &, esis. ptadsoril ( ainpatcn » & HN SteweR en bests + i call Shodan gs ’ sgnE Lie seousoult oe Ve *- ‘ey «. “y ; 7 am Fie - E 4 “a = ‘ ee T= va : . wey = Parastrophia sp.# Dinorthis subquadrata Hall # Dinorthis pectinella Hall # Hebertella occidentalis Hall * Hebertella insculpta Hall o # Plectorthis whitfieldi Winchell # Plectorthis plicatella Hall # Plectorthis fissicosta Hall # Dalmanella testudinaria Dalman * @ # Dalmanella hamburgensis Walcott # Platystrophia acutilirata James * Rhynchotrema capax Conrad * g # Rhynchotrema perlamellosa Whitfield # Rhynchotrema inaequivalvis Castlenau # Rhynchotrema neenah Whitfield # Zygospira modesta (Say) Hall * # Zygospira recurviyostra Hall # Hormotoma gradlis Hall # Lophospira quadrisulcata U. & S. # Bellerophon bilobatus Sowerby # Bellerophon sp. # . Helicotoma sp.* Trochonema umbilicatum Hall # Trochonema sp. # Cyclonema bilix Conrad * Tentaculites sterlingensis Meek & Worthen * i wield RO ere mr ety wa Aad ye it ae La pi Ye at we ar aK pty Asbo! er. Chat wb itoal sana ‘a Lp — an at ie ebisgo: & ‘Lista | fish ‘ 4 ul ieee Li Sei OFT, tofed ‘Fit w ali top rd [ial ottededlty + baeeeeee f oft nak ews i tavoats : re be} bo Bd [sian Led tion ke t ay | > sean Soe be gaceita by "5160 gt en's (EVES GH ONE zs aoolioau LLIG AWOTE or penza [ven0° Bivieviunaangt ‘in rdedocrelt a rid ont fi “i J. F amo tiolomygin a Hi if (eae)! aimee se toecayy Led) 2 is oa! y HOOT et ieaoget . % det ub dog 3 BT gata! if ia Ss a le Bei ena a S , i < ¥ a0 “i 1 ae nd | 1 a Se Se te pe r a, 1 hes i =a & a wy - Pterinea demissa Conrad * Ambonychia radiata Hall * Ambonychia intermedia Meek & Worthen * Orthoceras sociale Hall # Orthoceras bilineatum Hall # Cameroceras proteiforme Hall #4 Cyrtoceras camarum ? Hall # Gyroceras sp. # Isotelus maximus Locke # Nileus vigilans Meek & Worthen # Calymene senaria Conrad * # Ceraurus icarus Billings # Ceraurus pleurexanthemus Green # Pterygometopus callicephalus Hall # Dalmanites sp. # * Collected from the Upper Maquoketa beds @ Found in the Middle Maquoketa # Occur in the Lower Maquoketa j + Qarnod grits ee # i, ns ae 1 oe t- me ae fn OBE bat ae LAO ConA v4 £ : ee " ys of @dbemxotnt siaeynodaiee % >! rp we cies n ii r .Jish sileloos' ssteseddagrme aa, I 7 > - ‘ "Le onifid pax esonree ie Sa ieléte acon waerebesd | + ot os Ve et LEROtVe 5 : rs ZS fe " al i prt / > liv 7 j < OiAbniea j any Outil euifol nOwyeeee) it piel iexetwelg GYRE Ae j ' : vi : ft lanicecllian arqasanoayiers vy Oo. 690 Enel ho OPEN ogel, « oott betes Io @ : adssoupeé 6fbbin off och pu Kialowney tawol ott ah mus a7 é rf - { a eid "I 2 ‘ : ' iN The upper part of the Maquoketa strata is well exposed in Jackson County, about 7 miles west of Preston, where on one side of a ravine it is unconformably overlain by Silurian lime- stone, and on the other by Pennsylvanian sandstone. Section of strata exposed along a stream, about seven miles west of Preston, lowa. ee 2. Niagara limestone, with few or no fossils, in layers 4 to 12 inches thick- - - - - - - - 1. Maquoketa Shale, in alternating layers of shale and limestone, representing the upper portion of the Maquoketa, and containing many fossils- - - - 35 The following fossils were collected from the Maquoketa strata seven miles west of Preston, Iowa: Streptelasma rusticum Billings Rafinesquina alternata Conrad { Plectambonites sericea Sowerby Leptaena unicostata Meek & Worthen Strophomena neglecta Hall Strophomena rugosa Blainville Dalmanella tersa Sardeson Dalmanella testudinaria Dalman Hebertella insculpta Hall Hebertella occidentalis Hall Plectorthis whitfieldi Winchell Pterrinea demissa Conrad ByssoOnychia radiata Hall : s \ i 93 OCS as ) . f ) aor. Bt; 4 ~ Ol we ~ ~ ~ - ¥ be et, Lime E : 5 oe | . t - . iy al he Nie if . ~ - * = - - f 4 : ‘ - . - A . r me ago Lt bin . He t to dotttoa | . , ¥ 4 i agal a « \ al : t abcen Meicevigegie? wi Terie ‘yslioo raw siligaét satwoetiee (avel ,noteesd to teow, pote jl ‘ I Ee : ‘ Bank ils ius ES ght acho eRe bY. “paseteted fk na Lapegres “ee ‘adyvewdl eovines op be ina doers Kose tem, a tee: ameeed has enietaot | TL aan: noes aoa, aaa ) }, olfivatate ABOUT eremodtyosg Ge x iQ aob ie eetet Pace ¥ fama L staat buon Dae es my S talt- it g Ligeia ee Bie She vt tn ‘it “tole stein ay 1 eS _ Peet} | any bul Modiolopsis concentrica Hall & Whitfield Liospira cf. subconcava Ulrich Hormotoma salteri Ulrich Lophospira tropidophora Meek & Worthen Conradella dyeri Hall Cyclonema humerosum Ulrich Tentaculites sterlingensis Meek & Worthen The Maquoketa in Illinois Location and Area The Maquoketa formation was probably laid down continu- ously across the La Salle anticline in northern Illinois, but the Se niener portion of the axis of the anticline has since been eroded, exposing the Galena limestone and older rocks in that region. At present the Maquoketa formation in northern Illinois occurs in two areas, separated by the Galena limestone and older rocks. The | eastern portion extends from near Paxton in Ford County north to | Big Foot Prairie in McHenry County, embracing parts of Ford, Iroquois, Kankakee, Will, Kendall, Dekalb, Boone, and McHenry counties. The length of this area is about 190 miles, but its || width varies very much in different places, from 53 to 33 miles. The western area of Maquoketa has a somewhat regular || shape extending in a narrow belt in a southeast and northwest j direction from Van Orin, in Bureau County, to Fair Haven, in | Carroll County. F¥om Fair Haven up to the northwest border of the | State, the Maquoketa exposures are entirely irregular occurring in ' @ ‘ f ‘ : c ‘ - re r eb Se j ey vt TAI Tee nes attemen ‘pr eipel ants woot tables har onota sat snaLe an f Senteoe w@ Mh d ied woman’ e aL pitt bie bs | r diet " iT ha j cs _ +h i U At a) 1A * ; ee ‘ Py rs ‘ % RP » ¢ abs “Cea = | sistsened: otnsia Lota : a bee * poe oL310. Svaciecdre de welgnels i] M 7 7 fi: 2397 Las nail ey. axorfdohtroat? RA hosotadun jea:) inevh alleneraed a iwadtoarnl 2 *OnOLIYD (oes T et eee we \ Ge : anil tL sieled ane Che treaeias iat tse hoet abaey ey eid Re : Pri Ph “ yVeIWOD WES Higa ee Siti rae aa < Mode ab neta ok 26 celia sbeat - woos ty Halex og Thib at doi ay vaPe oo ar ci hil Site tg Atte adel eat Ts ST: Os a rtuusad gered oe on tveianal \ > ha: grt oh a hover oe Die ae F Wis, pI View snowing characteristic Maquoketa tonography, ££ with escarpment of Silurian limestone capping the hills. LIBRARY OF THE yrnvensiry OF nS - f- a ; 4 >= on Seqyocod MT aweaE ; he Joubeped abies LEers es Us * j ites se tar ; Cn oa | 2c1s4io gnivote wes a pe pe eo stot mr bhomasdi . a ’ ; i 4 i: Sgea ant tf 5 YUN J re Pee DE an ; i 2 ta - +) tn 1 M the lower part of the mounds and irregular patches where they har been protected by the overlying Silurian limestone. They are ex- posed along Plum Creek and Straddle Creek in Carroll County, Yellow Creek in Stephenson County, and along Apple River, Small- vw % ? pox Creek, Mill Creek, and Galena River, in Jo Davies County. Earlier Geological Work on the Maquoketa in Illinois. In 1870, Worthen, then State Geologist, studied the geology of Northern Illinois and gave a brief description of the Maquoketa formation in different localities. He mentions the Maquoketa strata in DeKalb County, on the north bank of the Kankakee River, where about 15 feet of inter-stratified green and blue shales and limestone beds are exposed. He also mentioned an exposure, about 30 feet in thickness, along the Fox River where the shaly beds contain many thin plates of limestone from which numerous characteristic fossils were collected including Dinorthis subquadrata, Dalmanella testudinaria, Hebertella occidentalis, Rafinesquina alternata, and other common species. In Kendall County Worthen found the upper beds of the Maquoketa formation well exposed at Oswego, directly underlying the lower strata of Niagaran limestone. The Maquoketa strata } here consist of hard, sub-crystalline, thin bedded limestone, con- taining many fossils, the most common of which are Tentaculites oswegoensis, Rhynchotrema capax, Hebertella occidentalis, Rafinesquina alternata, and many segments of crinoid stenis. Vv asiigu tottry 2 be Aint saditatauasdite, ae “Ba Bos: ree f2 cine baa A ig knw 9, notiare 9 + =o. a ee ts ~ (ak Lusaehss balls) el lated asa eat Figure VI, | View of upper beds of Maquoketa, exposed in the old shale pit, at Millsdale, Will County filixois. " ul MiKnk- tO apart ¢ a q O y t < / x ni ) a . a a r >) a Ps U “ ’ F i 7 » ’ ee \ ” f a. ' - . Ajong the Fox River, below Oswego, Worthen noted 'the Maquoketa Shale with thin bands of limestone, which contained ) Rhynchotrema capax, Hebertella occidentalis, Plectamnbonites sericea, and Rafinesquina alternata. He also described the almost continuous exposure of the Maquoketa along the banks of the river below Yorkville for about three miles, where the strata present the same appearance as those above Yorkville. He also found the fossiliferous Maquoketa shale and shaly limestone ex- posed on the AuSable Creek, in township 35, range 8, near the center of the west side of section 15. The Maquoketa formation in Will County consists of shale in the upper and middle parts, and argillaceous limestone | with some chert in the lower. About one-half mile east of DuPage the very fossiliferous thin bedded limestone, belonging to the lower part of the formation is exposed. In this county the green shaly clay forming the middle division of the Waquoketa has a homogeneous, fine-grained texture, and contains no fossils. Above In | Jo Davies County the Maquoketa Shale underlies the mound-like } elevations and is exposed on both sides of all the stream valleys. mots TaN ogee Bey aoe aD) “on, Hi oe aS ie iw .ovotaanhioege ab aad abst? _— fe, 4 ait Xo oa RO Msc indy he iff es steht olLlivatoY @v otgceher> ef sonetaaes BoA ean es BI4 A 3 apa ROE og, 4 ented —46. citetweds, ah > Sai eee ea. vA 76D naiicvsa 364 Or bee dy eK ¥ : ial, - a i. 164 Gtiwod “Piry BD Wipes odp fot alt {< it ovagoallive-Pis aig Stopes Oy * re Aa co site 2 Larsen cepdad 74 Tewo L, gxiy he wetototed .smefteaiL bebhed Aine hat re : e : - 3 = 7 locks fast ees dude Bt at TyVIa ee vist ens Ane: i sua ‘grr eameDad rg ghods' hee wane bre tealyy [eyet oN Pe 4s) ave ee 13 PTs fad: [iexvxs2 “bhi aapyed a ak ht cena f: fast sth ey ve ied ecer 2 A Lid 49 ba ins DEMOM BAS neitt rant: glass adsxonpalt wa? re ; i Ka a . — - Ne x 4 * f 7 : sothea ees) Lite ite ‘asin Atos 0 Pd f q Maquoketa Shale exposed along Rock Island, and Pacific railroad, mouth of Rock ‘Run, in Will County, Illinois. | The lower strata contain many minute fossils as species of W Nucula and Cleidophorus. The upper beds are rather thin and cream colored, while the lower ones are greenish-—blue and are separated by thin bands of marly clay; still lower the shales are exceedingly hard with few fossils. In Carroll County out- crops of Maquoketa strata occur. near the base of the bluffs, about one mile below Savanna, and about an equal distance above that town-lieek and Shaw state that a large amount of petroleum was obtained in the early days by distilling the black shales of this formation. Near Savanna and Tomlinson a part of the shale is as black as cannel coal and when burned gives out an oily bright flame for a considerable time. In 1909, T. E. Savage studied the faunal succession, and made the correlation of the pre-Devonian formations of southern Illinois where he described a small area of Richmond (Maquoketa) strata in Alexander County. He separated the rocks in that region into three formations, the Fernvale limestone | below, the Thebes sandstone and shale, and the Orchard Creek shale. Dr. Savage gave the detailed sections of the formations, | and described the strata and their faunas, and correlated them. with the Maquoketa stage in northeast Iowa and northwest Illinois. Detailed sections: - There is given below a number | of detailed sections of the Maquoketa strata in different parts | of Illinois: ine J c i <-> 5) 7 ee ats rosge ae eit Lhent ‘sob ire hy “yi vane taniat eta, aisd bok ta git surah c Ve = ft ’ “ ould alcasys $78 BBO TeWOn ene onkaw ; % OL! - F b ug rewolh Lf[ive- eke Vite Io ebmee eae ; = ca * ro Yowson Lents : sailaaet-aet cla bw ee ee . : ‘ ‘ Les 7 ’ ett “Ry ay LS eae ir o-o oie afeiota ae te Vee} c he Be | { [ry iM} bia a : pe 34 FeLi he om sens ara W 2 a f 24 4 i és rh t% LS Ad? ‘ro 0tBe & nos cio) oan Sis 4 to 4 tuoreer le berigd sotw boa {ees ewes 0 Cen i by) tg >S en itnoes & =ot oho he i ad sooue Condat edd bethiode, ogavedo 8 2 eOGt mae -o anoltaniot urgigoved Uy eas is ho Let 199 bine ermet ring va neta edt both b » i 6 ea Eitg i300 bis awe Leaedssom te sye ered age Wa WOLLE Hevip oho arene : = ‘ano age beniesacie a ; i - a ne aticq JQnI@t hhh Wh Skeets et exeuipak aay 19 ie OR” Section of strata exposed in the banks of Kankakee River in the vicinity of Wilmington, Illinois. 2. Shale, bluish-gray, with few or no fossils- - - - - - 1. Limestone, shaly to sub-crystalline, in irregular layers, very fossili- ferous- - - - — - = - 18 The following fossils were collected from the Maquoketa Istrata at Wilmington, Illinois: Lingulasma schucherti Strophomena incubvata KJ Rafinesguina Kingi Rafinesquina minnesotensis Rafinesquina alternata Strophomena planodorsata Plectambonites sericea Dalmanella tersa Dalmenella testudinaria Dinorthis proavita , yrs Dinorthis subgquadrata Hebertella insculpta lw) Hebertella occidentalis | Platystropnia acutilirata | Parastrophia divergens Rhynchotrema capax Ambonychia amygdalina ge mlaipewe ~ - SS : Be ' . ‘ = t & * yt Tis EV C8 sit Bi tay im poe h ° ot ff A EN a eae TiN OY - Oe - “ ~ “AC raBoOL oO 4 f > - tn ,5463 F 4 rf - a " P . [? = ' : - p 4 vv ' EL Le ] La ( ro rr ii a f wey 5 er e tadbyg ; b . sesossyims SELB ADN S283 i] fanned I paAluMeem) kik alles voto es foi ii: ‘ a E , Ty ae Nea oe net Deaogxs. SIRES | a satont gil so tetas » a4 oF tC» ‘ Seolitee @so2liwdmass, 14% ; : é ; Beta? fie fed i" we Sane ibocwed af Lee Laen, ay eae a, - @UIVaOTY 2 Ll Sept ioe ey 1 _ » 4 Jae og! Ser bong nih donde ie ae af Lape fits Steilsty ort eLietiedeits ae ah ‘ : * er A 4 \ ae +) nedee = tat i aT he oie Ne Hormotoma bellicincta Orthoceros sp. Cameroceros proteiforme Cyrtoceros houghtonia Section of strata exposed along the bank of ‘Waubansia Creek, in Oswego, Illinois. Silurian limestone. 6. Shale, yellowish-gray- - - ~ 5. Limestone, gray, dolomitic, in places crinoidal, weathered into thin bands 3 to 8 inches thick- - - - - Maquoketa formation. 4. Limestone, gray, massive- - - - Shale, calcareous, hard, bluish-gray- shale, Diuish<. - = = = = Shale, calcareous, bluish, in layers 6 to 18 inches thick- - = = The fossils listed below were collected from the Maquoketa strata in Oswego, Illinois. Strophomena planodorsata Strophomena rugosa Rafinesquina alternata Plectambonites sericea Dalmanella fairmountensis Dinorthis proavita Hebertella occidentalis Hebertella sinuata Sues mg jatelons tq aueningoste © oo ataanad fs shiupesaa te Soothe, Res | ioodussaet. ai phamesquaicbat: ienaiael | ees ee a stot Efad ecod aaftel rue “ne re “versgadttay A A! Lasoud eonaooromad f . Iie aerecos tg ia banord Line Te fel? seg : rt ° 7 . a) | aay , t ay set esisrsdgae a 2 haters, — — —- pad Ti - - ele SS eee = ee, | snoteems de — , . 4 er 4 , -~ “V5 235,-f [wo i 4 lade «2 . é : : =p _ re n titmofoh ,vet , ,ecotmem ity sag ogni Aateitieow Leb ioerese syoiNt seccohi. Ss oes Abe coiesek ae ? Pls vines .ja3g. ,edotesald. (se ae ial (sugstaoingn ,elann 956 | ; 1 le - oc ~seetilid” silat coe ca] j ty fe ‘ (2 OSTA Rea len rm slate ee L i 4 -Xo bd wort ERB L ap ce a: 7 A e af ~ aw welled tesa it eiigact at a y ae a” .s J :ehonis ot epee nk noes “ os | ‘BLOWN sunaptao ste el at strech aie Platystrophia acutilirata Rhynchotrema capax Zygospira modesta Tentaculites oswegoensis A detailed section, with lists of species of fossils of | the Maquoketa strata, exposed along the south bank of Fox River, one and one-half miles east of Yorkville, Illinois, is given below: 5. Limestone, hard, very fossiliferous, Feet Inches containing the fossils listed below-= - - - - - = - 9 Lingula deflecta Lingula riciniformis Rafinesquina alternata Dalmanella fairmountensis Zygospira modesta Pterinea carianota Raphistoma peracutum Calymene christyi Calymene fayettensis Isotelus maximus 4. Shale, dark gray, containing the following fossils- - - - Lingula sp. Dalmanella fairmountensis Pterinea carianota Calymene fayettensis + . ‘i ere aia ‘ _ pe ‘e) ots obeit aes aloney anaes gekihvas tee Oo afbeact Xo setesqs "to adete ie herdbas be Chaat ,tovis xol to xansd digos odd stots besonxe per os 2 -woled nevig at ,eatonhi£i .ol fivaiey te teae aati ere rere are seoretét tage veev . brant sods sikh oan era Same or ale 7 ‘ bao ak ae | wotell alinacl any Saelntataod TAA A -~ an »” * - ai = -"o fod “eos Iieb slugrtt starvtiniety efvigmdal pe. Stentedia sdiupasnal tak % alenedavomzist eifenanielt Sieabom aLigeas ae . sionsitso, sostrse4 2 oe motion ted nuigtatdqa “ivte Puro shady reo i etonsd saya onamgred. eam Loci au Ledoel is ort sities tog yety tab, | ee ee ae ee ~plisagt. palwad: 7 ae SLogeht - | alaaes ont 9 atacamat | 3. Limestone, argillaceous, with the fossils given below- = - - Dalmanella fairmountensis Pterinea carianota Calymene fayettensis 2. Alternating layers of shale and im- pure limestone, 35 to 6 inches thick, with fossils- - - - Rafinesquina alternata Dalmanella testudinaria Byssonychia radiata Calymene fayettensis 1. Shale, dark colored, calcareous. with a thin calcareous band crowded with fossils- = = - - = Lingula cf. iowensis Rafinesquina alternata Dalmanella fairmountensis Zygospira modesta Byssonychia radiata Calymene fayettensis Section of Maquoketa strata exposed in the north bank of the river, one and one-fourth miles —___©ast of Sterling, Tilinois: oo 3. Limestone, yellow to brown, dolomitic, in layers 4 to 10 inches thick, with few fossils- - - - - - - - - 2. Shale, bluish-gray, in layers alternat- ing with calcareous, very fossili- ferous bands- = - - - - = 1. Shale, sandy, with few fossils- Pa by dm * \ f o ie she en ee an LtScG aicdhe dei eandiiie The Maquoketa strata, east of Sterling, furnished the l fossils listed below: Strophomena incurvata Strophomena neglecta Leptaena unicostata Plectombonites sericea Hebertella insculpta Hebertella occidentalis Plectorthis whitfieldi Rhynchotrema capax Rhynchotrema neenah Zygospira modesta Byssonychia radiata Bellerophon bilobatus Cyclonema bilix Section of the MaquOketa strata exposed in the railroad cut, at Scales Mound, Illinois. Shale, bluish gray, without fossils- Shale, blue, with a reddish zone near the base, and another about 3 feet above the base, containing several small fossils- ~ - - = a 1. Dolomite, yellow, in layers 6 to 18 inches thick- - ~ - - - - =56 The following fossils were collected from the lower bate tinny? jpokirece te: yaae aceite soteopa 9 Anemone tsa sto lant mtemoddotte | Cie ISS eco lny artes T ied i= ~ ze oh Dh y x 5 a BOOLLSS Bee Fagor ise ff : : ; ne ilaryrads xSqeo anstPodoayit jeneeh estas. os ora. . “Te q ; taehom APLgdVevs, ' . siatbat aslinoynveaya autade lid aetaoncaitet xiiid smeno toys ‘ 0 . =! AS ad? mh besoexs etetta atetbepal egy To nota5a@. Ve es 19 a - . BLL ewes tosh tw ote de ttt A “J dt : ae ‘ 7 — ve STOR se ribies airidhw jeutd 4s toot 6 tuets rshtonme Das Golgi forever iin tesiop shee any £f A ly anh a ‘Sattuaees 1h 24 yb abe: } | ! 81 ate steyel snovaomil Base siaens syitentesis oo ree Valiasot uot ca , ’ : mu - y iovasnli bis @&faniea Io etawyel ghlvenies le-oity more r. As 5 - y Hoxton as hie Slee sae. bie ows) dla ce sag to series sae wot ,€f noltvoesp 2a eis Pane eas) Soe pheak eg se = ifoo syaw sl leet anine. ia’ autd ese * opniy f ain sine enenoituonte. aaa atenourand oc bw ssiononqopye om (isan te Selatan aon ew asd nodenom ait 3 , or, f ! ep ebepnthudoad elionan im he a a oe ae a 1) ee | | asboee ES ct 4 Rhynchotrema capax Rhynchotrema neenah Modiolapsis concentrica W/ Murchisonia sp. In the vicinity of Savanna, Illinois, the Maquoketa strata consist of about 100 feet of bluish shale, with few or no fossils, above which occur about 18 feet of shale and shaly lime- stone in alternating layers 3 to 5 inches thick, the layers of shaly limestone containing very numerous fossils, the more common of which are listed below: Streptelasma rusticum Streptelasma sp. Strophomena neglecta Leptaena unicostata Plectambonites sericea Dalmanella fairmountensis Dalmanella testudinaria Platystrophia acutilirata Plectorthis whitfieldi Rhynchotrema anticostiensis Rhynchotrema capax Section of Maquoketa strata exposed near Thebes, Illinois Orchard Creek shale member. . Feet 4. Shale, bluish-gray, calcareous, in which thin bands of concretionary, shaly limestone, 1 to Speen s thick occur pee dy ao ednenane oer sinbe Lites ae Aonpell “ety ,e romeglT PATER to “intel 9 on ic wet fv hh. .Afede qeseis «ty ~- OGL “a “-smil yfede bre Stade (fel ssee BL sides Lights! i 5 os StL end . Lotte. petonke Ss of, & arora ar Sedeos N yey houmnes stem elif? \aiieeot, evomaiiog ¥rey ery ‘wold ‘Home ‘ A rae be bas mu otlars, Amine Sa hgyt ae - a ESEE f SSM id re stoolaen stemor Gorse , hiee a2 aiatcooiat srontdgt Pie =~ -. ives aebinodussoolt * AAD SlLevesnvorris le Lie sive G eitenluutass bf tequbentad fi rt coy | niacbh bhige sitoottaygnle: vs . gn LoLorhbriw a tegiet peed, 6 hn tora payne isms snorsotoaah, . 898? eins ontderyti Sy it ee eT, te on, bee axe, siete * sso a weusoi tte eee Nao me = tak s gectupits Easlg jeonk br vlate - poxene ttetoass (tomo foitw gt svéeteoles “wt ie Hagel 3 vr “EUGO9 Soba , Semone Le er: View of Orchard Thebes sandstone, i River, two Illinois. Y) a4 Creek and one-half miles north of my, Thebes - vs f } ‘ x ‘ 4 On 4 - ow Gd “ as | ss bain. eae ; ae, nonscod AD 7 ae) isn Huinee © ; | ‘ieee Bu tedoal ate ‘Gh @¢isy owl: Sots Ba ga m0 tayo tloiv st at sv¥axrte. siesaiognaieee pmet oar oT asm ecard o¢ elaine le) (eee es PA j ruOoR ia 4 ha ay | Pe ax a Az. mays zwoat le s(teaee 6°se4i05% Be a P i a | fe | pi a Tét S< +1) ¥y Bd aw) &-¥ ‘re, : Moljeaut emekiatcaass fetobedusiq sasietoass: ciate ts stiupratr ren bran loses} elfenan feo aus haa th 2'Efenan ful , BY bad ian We diadaohia avo Sunent: sub-set a 7% oo ae At ietinaby . “ alaaneoned) eaiioab ea A 2 We : ¥ Par mei tie 108 | akinerearba ah nay Comparative Table of Fossils. The following table shows the species of fossils in the Maquoketa of the different areas. The names of those which j occur in Wisconsin are indicated by “x” in the first column; those which occur in Iowa ee a "X" in the second column; those which occur in Northern fllinois by an "X" in the third column; and those which occur in Southern Illinois by an "X" in the fourth column: Astylospongia sp. Hindia parva Climacograptus putillus Streptelasma rusticum Stomotopora arachnoidea Corynotrypa inflata Protocrisina exigua Ceramopora Peioeeporelia granulosa CeramO&orella ohioensis Ceramoporella whitei Coehoclema oweni Coeloclema sp Crepipara hemispherica Crepip.ora simulaus Analotichia ponderosa ns Ale a4 a ar Fy eat “ yy PE . ‘ss wat + ae ne ce 4 7 ba colial. sta aie ai oes a id eh OR" By. ve guot Ki TWIDSE el "XY Ap ot atend fee i eae oe vs yo aetoniicl wredtess ob setesecee ati L fcc “aay ere y Koro T Cees es=8 [ote a sepbontteie stagoeom oY Se Bae ae ; 4,2 ghee cn oité C oe ; : i et oan Rie i alee she teansy oho \ vy a ae Asatte ae w ~ ‘i es Analotichia sp. Bythotrypa epidermata Bythotrypa laxata Cyclotrypa n. sp. Peronopora pavonia Homotrypa communis Homotrypa flabellaris Homotrypa gelasinosa Homotrypa similis Homotrypella rustica Mesotrypa orbiculata Mesotrypa patella Mesotrypa sv. Heterotrypa affinis Heterotrypa prolifica Heterotrypa singularis Heterotrypa subramnosa Stigmatella interperosa Stigmatella nicklesi Stigmatella spinosa Stigmatellea sp. Petigop.ora sp. Atactoporella schucherti Cyphotrypa stidhami Cyphotrypa wilmingtonensis Constellaria punctata Constellaria polystomella 4 > « Siaover asi “hha: y _ Alta tiscgeas seyret e th exe Bly. scouted fag Auyteom | hittele. cagthaam ini Xs | egkielr ef loqgrim x . ei sluridye meee x 7 | 2 Petstey wavitons iyi ¢ US Saee ene af ~ 69 LPL Tesg agytronedte ye ! elraisgule eqystoteee 4 ; - neon "ee hart to tesa + a | > ag ee TOoMectaM eliahem By 7 ; Vial fie an Bent i ’ | a . : . Ede Dio le 2 Eimg ~ * . . sootiosg af x -45- Nicholsonella cunulata Nicholsonella carnula Nicholsonella punctata Nicholsonella n. sp. Bythopora delicatula Bythopora meeki Bythopora striata Fridotrypa granulata Eridotrypa simulatrix Liocbmella solidissima Amplexopora ampla Amplexopora sp. Monotrypella quadrata Rhombotrypa crassimuralis Rhombotrypa quadrata Rhombotrypa subquadrata Rhombotrypa sp. Hallopora crenulata hallopora subnodosa H&lopora ramosa H@llopora cf. subplena pa SPY A A dt CB Hallopora imbricata Colloporella ? lens Batostoma prosseri Batostoma variable Batostoma varioum a Hemiphragma imperfectum KISTOONY £ Be] oe ; iG eo ut Bian oe ee a ~ a ol , | atelagn’ avogod pia tener squid bs tivtefvals Seyedar x , | enlas ini ton sits ve a Siqne etree. 68 #106 Say DDS al tegen ‘Sitio ETS | . . o finatas: equitvm : moe ayn 2 : | ae “aqytiod ¥ see ‘ana A . Diplotrypa sp. Monotrypa nodosa Monotrypa sp. Anophragma mirabile Tremotop.ora calloporoides Fenestella granulosa Arthroclema angulare Ptilotrypa obliquata Pachydictya elegans Pachydictya fenestelliformis Pachydictya firma Pachydictya gigantia Pachydictya hexagonalis Pachydictya magnopora Pachydictya splendens Helopora imbricata Phenopora wilmingtonensis Dicranopora emacerata Dicranopora fragilis Arthropora cf. shafferi Lingula covingtonensis Lingula deflecta Lingula iowensis Lingulasma schucherti Crania sp. Rafinesquina alternata cs I A oo ie Mee. ea A - Pas .Lidathy ane f TER et +“, Lose ced s\wiebbybes ; 2 1 » aie S.5 a Ss as 2.135 on es = 1 Saal , : a0 Z : . 1 6 60ne fae Rs uty Web erties 3 lw at 4 aw rawianic 7.6 han Gage aaa Oy er F Rt od cts coca . peed) - Cee Rafinesquina kingi Leptaena unicostata Plectombonites sericea Strophomena fluctuosa Strophomena incurvata Strophomena neglecta Strophomena plandorsata Strophomena planumbona Strophomena trilobata Strophomena wisconsinensis Parastrophia sp. Parastrophia divergens Dalmanella fairmountensis Dalmanella hamburgensis Dalmanella tersa Dalmanella testudinaria Dinorthis subquadrata Dinorthis proavita Hebertella occidentalis Hebertella insculpta Hebertella sp. Hebertella sinuata Orthis tricenaria Platystrophia acutilirata Plectorthis whitfieldi Rhynchotrema anticostensis ee oO oo i 2 2 | ‘ede aah evs “OR a mn iS hed is 7 oa tuodaagy VES ga Oud oeee. svg F . mM gt olrivorth enseedar jsslyes sasnongews &eetohdasiy sieweigoms — - if . . 6c AUMOU MUTA LS BESO Ome ; icavoliny ahamedes etaisniecose iw anemigige tae ¥ 7 2 are , Y ayes ; sidegesas ‘ eLenet avon “2 et test : pila : “ - (3 kegeote ite ect x Tie ast sizsathats ad oa ve x : Reet bampdion etdsig) : a ; . = ie oe a¢iveeng aidevogtd at osaeaee blindasbhtos be Rhynchotrema capax Rhynchotrema inequivalvis Rhynchotrema neenah Rhynchotrema perlamellosa Zygospira modesta Zygospira recurvirostra Bellerophon bilobatus on 9 i oP | Bellerophon sp. Pleurotomaria depaperata Lophospira pulchella Lophospira quadrisulcata Hormotoma bellicincta Hormotoma gracilis Helicotoma sp. TrOchonema sp. Cyclonema bilix Tentaculites oswegoensis Tentaculites sterlingensis Conularia sp. Ctenodonta fecunda Ctenodonta obliqua Clidophorus neglectus Vanuxemia sardesoni Pterinea carianota W¥tertyppat ae 7 Pg arneaad ‘ae aug - sto Ls ous fs6 xma1tonen | av eshom atkaee sirdeotty sas oe% wehqeome augede [id nodgote tal ‘oR coders f Lill starac Megat alt anode “eLiods ine orbqaong £ Ve fuerrs neNe & sigaodag stosnottisd eae elebonry a “78 -bu0d Orn re) Sasnod C - os i Pac alte sono tong elacsouoweo. W610 chenegad 1890p te ¢ ~ r \ K a ay ‘ « rl rh > : oe U , 4 ‘é i i i af a! 4 ia \ t ’ ‘ me ; ae 7 at 1 J A | 3 4 _ ¢ Pterinea demissa Byssonychia intermedia Byssonychia radiata Orthoceras bilineatum Orthoceras sociale Orthoceras sp. Cyrtoceras camurum Cyrtoceras houghtoni Cameroceras proteiforme Gyroceras sp. Nileus vigilans Isotelus maximus Isotelus sp. Calymene christyi Calymene fayettensis Calymene senaria CeraUrus icarus Ceraurus pleurexanthemus Dalm@aites sp. Pterygometapus callicephalus Endymion sp. 3 7 if i: nf ae ; i: a , thea Bh: ine aashsol * eto aul 3 =. | ik ‘oo "Eee aaron sixsoods A | cae otindort eure Ht * | ; : ety wee 7 , : | het tet “a pt pas ay a? analy bt nurad | ae Ue eae cae Se auae bee ein : meee or cate ee x | ' oe Behe eax rs. anid suse eth ; + he ei epics nao Tine Mh aniadqest £ fac" if su es sf ¢ & Lhe ip, ¥ vi . : Ay " b = mil Fe P) 0 ee Pad - a ? me rT A - ‘ fe ace , = ig ike rg ay ; me he opie ay ng ; — <1 7. |? 7h," : cA cd é 4 A a Una Ves » eee _ Distribution of Species and Its Significance. It will be noted that a much larger number of species in the above table are listed from Northern Illinois, than from } Towa or Wisconsin. This is on account of the fact that collections | of Maquoketa fossils have been made from several more localities in Northern Illinois, than in Iowa or Wisconsin. It will be seen that almost every species listed from either Iowa or Wisconsin appears @is0 im the list for Northern Illinois. This is interpreted as indicating that the Maquoketa strata in Northern Illinois, Iowa, and Wisconsin belong to the same geological province, which means that they were deposited in an epicontinental sea that had the same ocean connection. The Maquoketa sea that covered northern Illinois, Iowa and Wisconsin advanced from the Artic regions, as is known from the presence of the characteristic fossils of the above list, farther northwest in Canada. The fossils that came from the rocks of this age in Southwest Illinois include the following species that do not occur in Northern Illinois, Iowa or Wisconsin: Climacograptus putillus, Lingula covingtonensis, Hebertella so., Orthis tricenaria, Conularia Ssp., Endymion sp., and Isotelus sp. This marked difference in the } fauna of rocks of the same general age as the Richmond formation in Southwest Illinois compared with the fossils of the Maquoketa formation in Northern Illinois, Iowa and Wisconsin, is interpreted | 2s indicating that the strata of this age in Southwest. Illinois belong to a geological province different from that of the liaquoketa et rand Lo ais To Jaugoge ato at ehtt. ga if ke i 19Ve58 MOT saben mood even af ke gat 2 } art3 ae 9 # tI .stetcosi¥ 16 evol HL-nagd cee avatar ogi wo itt hedell asiogima: a j aN ai 1 duL si sin? .sionilil trsh@iren tot Sees x ,ealtentifl nrsdivell ni ete edextougal saveene iriw ,eonivotg lagipolos ae oft of nioted. Be E os Sen tadg 258 Javnornisneoige ne ab begiaogeaies ato: uvectvon Boisvos, tait sve efssonpeh On7 er eeee oe": f ; / fe viele ont al 22 ,sHotset oboTA. ofd mort bsadavbe niemooe : I \ “sa ae, P ‘ : ‘ es ; : 7 eel E io altasot sidvaivegostaro eas to SoReeetaE bans ot teawiiae to eisox of ‘ott smas cand affesot sd?) Te - , f al . ; at ; ES fit daetossae sat htetfo }-eas shutont atooili{t - , r Soo efi eke jNosat® Do -e¥ei sekofebe P z is tes akndod Sede eiLatiodel co saamanaean z One sad a = SISTA Seles Bete are autogost hae cor ii of ayid ae ana Jereten.. oni g oupS Melee Se pthene sat détw bersanioa’ a ~ — hy bodsigtedine et ihatiage Bike Byol etotligt @ u y YF Ae he akoni ltd: Se omtages aL ae sisty A: eke i [= artd> te SSoACRBLM - 4 ie Bia 4 ta a ay Dy Ley a i i ’ \ = f AFG we b 4 ae aN Paes, }farther north in the Mississippi Valley. This southern province his thought to have had sea connection southward with the Gulf of Mexico. It is probable that during early Maquoketa time the seas in these two provinces, one from the Arctic region and the other }irom the Gulf of Mexico region, mingled over a belt in central Tilinois and northern Missouri, but in middle and late lMaquoketa time these seas were probably separated by a land barrier in the region of Gentral Illinois and northern Missouri. The relations of these provinces may be seen on the Paleographic map of Richmond |time, shown in figure 10. In Indiana and Ohio the Richmond strata are equivalent in age to the Maquoketa of the upper Mississippi Valley, as shown by the large number of characteristic fossils common to both areas, but the Indiana Richmond strata contain many species of fossils that are not known in northern Illinois, Iowa, Minnesota, or Wisconsin, or in the southwest Illinois province. The fauna of the Richmond strata in Indiana and Ohio resemble that of the Maquoketa in the northern Illinois province much more closely than ithat of the strata of similar age in southern Illinois, but they #also contain many distinctive species that are wanting in the | Maquoketa strata of the Upper Mississippvi Valley, such as | Agelacrinus faberi, Ectenocrinus simplex, Catazyga headi, Dinorthis iretrorsa, Rhynchotrema dentata, and Commdella dyeri. The follow- ing species are common in northern Illinois, but are not found in |the Richmond of Indiana and Ohio: Plectorthis whitfieldi, |Rhynchotrema anticostenensis, R. nennah, Tentaculites sterlingensis, a ~ 0 -~ a3 0s¢nnik Awol ‘afositi{i ores 19d att coma Sou, - ~~ a ZH - +z - one Sie COL te fe’ :