REPORT No. 52
The Faunas OF THE Lower Palaeozoic Carbonate Rocks in the Subsurface of Saskatchewan
by JOHN E. BRINDLE 1960 I
DEPARTMENT OF MINERAL RESOURCES Petroleum and Natural Gas Branch Geology Division
HON. J. H. BROCKELBANK J. T, CAWLEY Min lat• Deputy Mlnlat•
PROVINCE OF SASKATCHEWAN ABSTRACT
The fossils studied in this report (over 80 species, principally coelenterates and brachiopods) were obtained from all well cores taken in the Lower Palaeozoic carbonate rocks of Sask, atchewan (Ordovician Bighorn and Silurian Interlake groups ) available to the writer to the end of September, 1959. The fauna! assemblage is presented from, and an age ascribed to each of the stratigraphic units in this succession. The Bighorn group appears to be of Upper Ordovician age for most of its thickness. The Ordovician,Silurian boundary may occur within the Stone, wall formation, the uppermost unit of the Bighorn group. The Interlake group appears to include both Lower and Middle Silurian strata. There is no evidence of angular unconformities or erosional gaps within or between the Ordovician and Silurian strata. Correlations are proposed between the Ordovician and Silurian carbonate rocks of Saskatchewan and those of eastern Montana, northern Wyoming and the outcrop areas of Man, itoba. The correlations of Porter and Fuller (1959, Amer. Assoc. Petrol. Geol., Bull., vol. 43, No. 1 ), and Ross (1957, U.S. Geol. Surv., Bull. 1021,M), are reinforced. The fossils are illustrated by photographs wherever possible. CONTENTS Page I .- INTRODUCTION...... ·········································· ...... 7
I I .-ACKNOWLEDGMENTS ...... ················· ...... ··········· ...... ············ 8
III.- STRATIGRAPHY, SuccEss10N AND NOMENCLATURE...... 9 (a ) General...... 9 (b ) Ordovician...... 11 (c ) Silurian...... 12
IV.- PALAEONTOLOGY, CORRELATION AND AcE...... 12
A. ORDOVICIAN...... ····································· ...... ······ ...... 12 ( i ) Yeoman Beds ...... 12 (ii) Herald Beds ...... 16 (iii) Stoughton Beds...... 17 (iv) Gunton Beds...... 18 (v) Stonewall Beds ...... 18 (vi) Age of the Ordovician Strata ...... 19
B. SILURIAN .. ··· ··················································· ············· ·················· ...... 19 (i ) Rupert Beds...... 19 (ii) Hanson Beds ...... 20 (iii) Risser Beds...... 22 (iv) Age of the Silurian Strata...... 22
Bibliography...... 23
Appendix...... 24 ILLUSTRATIONS Page PLATES-Plates I to VIII with explanations follow...... 29
FIGURES }.-Location Map ...... 9 2.-Characteristic Gamma Ray;Neutron well;log of the Lower Palaeozoic carbonate rocks of southeastern Saskatchewan...... IO 3.-Age and Correlation Chart of the Lower Palaeozoic rocks of Saskatchewan...... 14 TABLE !.-Vertical Distribution of Species in the Lower Palaeozoic Carbonate Rocks in the Subsurface of Saskatchewan ...... 15; 16 I. INTRODUCTION
The material on which this study is based consists of a collection of Lower Palaeozoic fossils from well cores taken in the Ordovician and Silurian carbonate rocks in the subsurface of the Province of Saskatchewan. The report is intended to supplement the available accounts of the stratigraphy of these rocks, notably those of the Saskatchewan Geological Society (1958 ), Porter and Fuller (1959 ), and Kent (1960 ), by pre~ senting an account of the faunal assemblages so far obtained from each of the stratigraphic subdivisions of these rocks in the subsurface of Saskatchewan. Correlations with adjacent areas based on these faunas agree with those already produced relying on "non~sequential" arenaceous and argillaceous "marker beds" within the carbonate succession (Saskatchewan Geological Society 1958, Cumming, Fuller and Porter, 1959 ). Fossils were collected from all cores taken in the Ordovician and Silurian carbonate rocks of Saskatchewan available to September 1959.
7 I I. ACKNOWLEDGMENTS
The writer wishes tQ acknowledge the assistance and co operation of his colleagues in the Department of Mineral Resources during the course of this study.
8 III. STRATIGRAPHY, SUCCESSION AND NOMENCLATURE
(a) GENERAL For detailed accounts of the stratigraphy of the Lower Palaeozoic rocks of Saskatchewan and adjacent areas the reader is referred to Porter and Fuller (1959 ), Saskatchewan Geological Society (1958 ), Kent (1960 ), Andrichuk (1959), Kupsch (1953 ), Stearn (1956), and Baillie (1951, 1952 ). In brief: Ordovician and Silurian carbonate rocks are present through, out the whole of the northern part of the Williston Basin and adjacent shelf areas south of the Canadian Shield in Saskatchewan and Manitoba, outcropping in southern and west-central Manitoba and east-central Saskatchewan. Figure 1 shows the erosional edges of the Ordovician and
--~· ...
BELT Mrs
' ~ ELE CQICSNOWY NA MfS.
MONTANA
PIER At Aleo •i1h,n which foult, wert colltcttd from well corn.
Erost()rw,I ede;t of Ordovicion corbonolt 1troto.
Ero,lonol edge ot Silurion stro10 . SC.IL[ IN WILCS ,oo $0 0 200 t-, ·t:::, t=::::1 •
Fig. I- Location Map Silurian carbonate rocks in Saskatchewan and Manitoba. In Saskatche... wan these rocks reach a total maximum remaining thickness of some 1350 feet on the International Boundary in the southeast of the Province, the thickness decreasing northward to the erosional edge. 9 Over eastern Saskatchewan the lowest Ordovician carbonates (Yeo; man Beds) overlie the sandstones, silts tones and shales of the Winnipeg formation, also of Ordovician age, with apparent conformity. However, over part of western Saskatchewan the Winnipeg formation seems to be absent, and here the Ordovician carbonates appear to lie unconformably on the Cambrian and lower Ordovician sandstones and shales of the Dead;
z W
000
z <{ Q. ii: ::::, HANSON 9000 ::> 0 _j a: BEDS u'i (!) w w ::.:'.: Ji.. ..['IQ!.kl! _ _j <( 0 _J ,100 0 a: w :!E zt--
SIZOO
RUPER T BEDS z a:: :3~(/) STONEWALL ------BEDS -- :=:,.. t•oo GUNTON BEDS (/) ..,0 CD ,~oo Q. ::::, z 0 <{ a: 0 (!) z 0> a: KOO 0 (/) 0 I 0 a: (!) w 0 ai m a:: a: w w ~ a... a:: '700 a... YEOMAN ::> 0 w BEDS a:: ... HOO r WINNIPEG FORMATION to. 9941' Fig. 2- Characterlstlc Gamma Ray-Neutron well-log of the Lower Palaeo zoic carbonate rocks in southeastern Saskatchewan. 10 wood formation. Except for a small area in east;central Saskatchewan where Cretaceous rocks form the overlying deposits, the Silurian strata (Interlake group) of the Province are unconformably overlain by rocks of Middle Devonian age. The nomenclature used in this report for the Lower Palaeozoic car; bonate rocks in subsurface sections is shown in Figure 2, together with a typical gamma ray;neutron well;log. The nomenclature is that of the Saskatchewan Geological Society's Lower Palaeozoic Names and Corre; lations Committee (Saskatchewan Geological Society, 1958 ), except that the term Bighorn group has been substituted for Tyndall group as being more widely acceptable. The Rupert, Hanson and Risser Beds equate with the Lower, Middle and Upper Interlake Beds, respectively, of Porter and Fuller (1959). The use of the term "Beds" by a number of authors in this area (Saskatchewan Geological Society 1956, 1958; Porter and Fuller, 1959; Cumming, Fuller and Porter, 1959; Brindle, 1960) for para; time, marker;defined, stratigraphic units is retained here. The succession is divided into units using thin, "non;sequential" , elastic (argillaceous and arenaceous) "marker beds" of great extent, which represent very widespread temporary interruptions in the carbon; ate sedimentation. The units are believed to be para;time;rock units, or sedimentary stages (Saskatchewan Geological Society 1956, 1958; Porter and Fuller, 1959; Cumming, Fuller and Porter, 1959) and as in the case of the Mississippian strata of southeastern Saskatchewan, which are similarly divided (Fuller, 1956; Brindle, 1960 ), no palaeontological evi; dence inconsistent with this belief came to light during the course of fauna! studies. The p, q, t, u and v horizons (or "markers") are those of Porter and Fuller (1959 ), the marker bed in the lower part of the Hanson Beds (Middle Interlake Beds) which was not named by Porter and Fuller is here termed for convenience the w horizon. (b ) ORDOVICIAN The Yeoman Beds, which reach a maximum thickness of some 370 feet in Saskatchewan, are composed largely of brown and grey, often mottled, dolomitic, fossiliferous;fragmental limestones. A thin develop; ment of argillaceous dolomitic limestone, the p marker of Fig. 2, marks the top of the unit. The Herald Beds are comprised of dolomitic fossilifer; ous;fragmental limestones and argillaceous dolomites, with bedded pri; mary anhydrites in southeastern Saskatchewan making up two evaporitic cycles. The Herald Beds have a maximum thickness of approximately' IOO feet in the Province, and the top is marked by another development of argillaceous dolomitic limestones. In southeastern Saskatchewan the overlying Stoughton Beds consist of fossiliferous;fragmental limestones overlain by a development of dark blue, calcareous shales (the Stony Mountain Shale member ). Elsewhere in the Province the unit is made up of dolomites or dolomitic limestones. The Stoughton Beds reach a maximum thickness of 70 feet in Saskatche; wan. Over the extent of the Stony Mountain Shale member, the top of the Stoughton Beds coincides with the top of the former, and an argill; aceous marker bed at this horizon extends a short distance beyond the depositional edge of the Stony Mountain shale marking the top of the Stoughton Beds. Still further from the edge of the Stony Mountain Shale, however, this marker, too, is lost, and the Stoughton Beds merge with the overlying Gunton Beds into the undifferentiated Stony Mountain Beds. The Gunton Beds comprise a sequence of dolomites and dolomitized 11 fossiliferous,fragmental limestones reaching a maximum thickness of approximately 70 feet. Sandy, dolomitic shales averaging 5 feet in thick, ness mark the top of the unit. The Stonewall Beds are composed of thinly-bedded dolomites and mottled, dolomitized fossiliferous,fragmental limestones with a bedded, primary anhydrite in the lower part of the sequence in the southeast of the Province. The unit has a maximum thickness of about 100 feet in Saskatchewan. The top is marked by a widespread bed of argillaceous, sandy dolomite, and a prominent and equally widespread marker of a similar lithological character (the t marker, Fig. 2) occurs in the middle of the unit. (c) SILURIAN The Rupert Beds consist of pale fine-grained dolomites interbedded with fossiliferous fragmental limestones. Relatively thin intercalations of sandy materials occur. One of these (the v horizon ) marks the top of the unit. Another, in the middle of the unit, was named the u horizon by Porter and Fuller (1959). No unconformity is apparent between the Rupert Beds and the underlying Stonewall Beds. The maximum thick, ness of the Rupert Beds in Saskatchewan is approximately 150 feet. The Hanson Beds, which reach a maximum thickness of about 300 feet in the Province, comprise a sequence of pale, fine-grained dolomites and dolomitized fossiliferous,fragmental limestones very like those of the Rupert Beds. Occasional thin, dark, argillaceous dolomites and shale bands occur. The top of the unit is placed below a development of reddish sandy, argillaceous dolomite which marks the base of the overlying Risser Beds. An intercalation of argillaceous dolomite in the lower part of the Hanson Beds is the w marker horizon of this report. The Risser Beds are buff and cream, fine-grained, sometimes chalky, in part vuggy, dolomites, with a reddish sandy dolomite at their base, as previously mentioned. The maximum remaining thickness of these beds in Saskatchewan, beneath the pre-Middle Devonian unconformity is approximately 180 feet. IV. PALAEONTOLOGY, CORRELATION AND AGE A. ORDOVICIAN (1) YEOMAN BEDS FAUNA (Plates I and II ) ? Rosenella sp. Grewingkia cf. robusta (Whiteaves ) Streptelasma cf. goniophylloides Teichert Streptelasma cf. latusculum (Billings) Streptelasmids Nyctopora sp. Monticulipora cf. mammulata D'Orbigny Bryozoa ? Holtedahlina sp. Megamyonia cf. unicostata (Meek and Worthen) Megamyonia sp. Rhynchonellid Strophomena cf. hecuba Billings 12 Strophomena cf. rugilifera Wang Strophomena sp. Strophomenids Gastropods Pelecypods Ostracods The stromatoporoid recorded here as ? Rosenella sp. appears to have close affinities with the Silurian to Lower Carboniferous cosmopolitan genus Rosenella. A decision as to whether this is a different genus, or an earlier occurrence of Rosenella than has been hitherto recorded awaits further investigation of the specimen at hand. Grewingkia robusta occurs in the lower part of the Red River formation (Selkirk, i.e., Dog Head member, Sinclair, 1959) of Manitoba, and in the lower part of the Bighorn dolomite of Wyoming, in strata correlative with the Red River formation (Ross, 1957 ). Streptelasmids near S. gonio, phylloides occur at the base of the Bighorn dolomite. Streptelasma latus, culum appears to be a species with a fairly wide range. It was first recorded from the Jupiter formation, of Silurian age, in Anticosti Island. Ross (1957) records S. aff. S. latusculum from the uppermost part of the Big, horh dolomite in Wyoming in beds equivalent to the Stony Mountain Shale member. Baillie (1952) records Streptelasma rusticum and S . cf. rusticum from the Stony Mountain Shale of the Manitoba outcrops. With regard to streptelasmids of the S. latusculum type in western North Am, erica, Duncan (1956) writes "Corals of this sort are probably the forms identified as Streptelasma rusticum in older reports.", a comment which may be applicable to Baillie's record noted above. Nyctopora occurs in Middle and Upper Ordovician rocks in many parts of the world. Megamyonia unicostata is recorded from the Red River formation in the Manitoba outcrops and in eastern Montana where it also occurs in the Stony Mountain Shale member. In Wyoming it is present in the Leigh member of the Bighorn dolomite in beds probably equivalent to the upper part of the Red River formation. Strophomena hecuba occurs in the Stony Mountain Shale of eastern Montana and in equivalent beds in the Big, horn dolomite. Strophomena rugilifera is present in the Red River forma, tion in eastern Montana. From the fauna! assemblage presented above, and that of the Herald Beds which follows, it appears clear that in the Red River interval of Saskatchewan we are dealing with the same sequence of rocks making up the Red River formation of the Manitoba outcrops and the Red River Beds of the Williston basin to the south. The correlations proposed are shown on Figure 3. The correlation of the Red River Beds as a whole with the Red River formation of the Manitoba outcrops, of Porter and Fuller (1959) is supported. The nomenclature of the divisions of the Red River formation in the Manitoba outcrops is that of Sinclair ( 1959 ), who has demonstrated the equivalence of the Dog Head and Selkirk members, choosing to retain the former term for the lower unit as likely to cause less confusion than the term Selkirk member (until recently regarded as lying above the Cat Head member ) (Sinclair 1959, p. 6). Sinclair suggests that the Cat Head member and the Dog Head member will correlate with the Herald and Yeoman Beds, respectively, of the subsurface. At the present time, and in the absence of evidence to the contrary, this correlation seems to be the most logical one. The Dog Head member is composed chiefly of frag, mental dolomitized mottled limestones and the Cat Head member of very fine-grained limestones and dolomites, with chert. 13 :! '.'I w Q~ THIS REPORT MANITOBA OUTCROPS EASTERN MONTANA SUBSURFACE fll (» """ ( Interlake ofter Stearn (1956) , units A to O ( Ross ( 19 57)) =.. SASKATCHEWAN SUBSURFACE ofter Baillie ( 1951 ), Ordovician ofter S,ncloir ( 1959)) II;'=.. j:l., ~o tr~ (» ... c Risser Beds ~ ~ a. 0 0.: ·;:: 0. :'t ::, •~ Q ii' Table 1.- Vertlcal Distribution of Species in the Lower Palaeozoic Carbonate Rocks in the Subsurface of Saskatchewan. -<: :r: rn C) rn ;x:, ;x:, ~ 8 c 8 c 8 ol c ::, ::, i ~· 3 OQ ~ ~ .... I» 5: ::r 8 .... ~ ::, .... ::, ~ ... ::, 0:, 0:, 0 0:, 0:, ::, ~ 0:, ~ a a 0:, 0:, a c. a l ~ "' "' "' a "' c. "' "' "' "' ------Clathrodictyon Jastigiatum Nicholson ...... x x Clathrodictyon cf. regulare Rosen ...... x Clathrodictyon cf. striatellum (D'Orbigny) ...... x Clathrodictyon sp...... x Clathrodictyon sp...... x Labechiella sp...... x ? Rosene/la sp ...... x Stromatopora cf. constellata Hall ...... x Stromatoporella sp...... x Stromatoporoid...... x Dinophy/lum hindi (Stearn) ...... x Grewingkia cf. robusta (Whiteaves) ...... x Streptelasma cf. goniophylloides Teichert...... x Streptelasma cf. latusculum (Billings) ...... x x Streptelasma trilobatum Whiteaves...... x Streptelasmids...... x x x Eofletcheria sp ...... x Favosites cf. Javosus Goldfuss...... x Favosites gothlandicus Lamarck...... x Favosites cf. gothlandicus Lamarck...... x Favosites niagarensis Hall ...... x Favosites niagarensis lundarensis Stearn...... x Palaeofavosites pou/seni Teichert...... x x Palaeojavosites cf. transiens Steam ...... x Favositid...... x Halysites (Catenipora) gracilis Hall ...... x Nyctopora sp...... x Syringopora sp...... x Tabulate corals (2spp.) ...... : ...... x Batastoma sp...... x Fenestellid ...... x Hallopora sp...... x Monticulipora cf. mammulata D'Orbigny...... x Bryozoa...... x x x Brachyprion cf. inflatus Stearn ...... x Brachyprion paskoiacensis Stearn ...... x Brachyprion cf. paskoiacensis Stearn...... x Brachyprion Philomena (Billings) ...... x Camarotoechia cf. indianensis (Hall) ...... x Catazyga sp...... x Clintonella bailliei Stearn ...... x Diceromyonia cf. ignota (Sardeson) ...... x Diceromyonia cf. storeya Okulitch...... x ? Diceromyonia sp...... x Dinorthis (" Pionorthis") cf. occidentalis Okulitch...... x Fardenia cf. ele,zans (Prouty) ...... x 15 CJ) C) CJ) :;o :;o -< :r: rt rt :r: n, 0 c 0 c 2 .,... c :::, :::, ~ ~· 3 (IQ 8 n, 'R... is ... ., 0:: ::r :::, ~ rt :::, :::, rt 0, 0 ~ n, :::, 16' a. 16' 0, a. 16' l f 16' a. n, a. "' "' "' a. "' a. "' "' "' "' ------= ---- Fardenia e/lipsoides Stearn...... x ? Fardenia sp...... x ? Ho/tedahlina sp...... x Lepidocyclus cf. gigas Wang...... x Megamyonia cf. ceres (Billings) ...... x Megamyonia cf. nitens (Billings) ...... x Megamyonia cf. unicostata(Meek & Worthen) . x x x Mi~~tr.i~ -- ~f: .. ~:.~~: .. '.\l~~~·-·(·19.~9 )_ '. .. ~.l.'... 9.· x Megamyonia sp...... x ? Opikina cf. limbrata Wang...... x ? Opikina stonewallensis Stearn...... x Orthids...... x x Rhipidomella cf. uberis (BilJings) ...... x Rhynchonellid ...... x Stropliomena hecuba Billings...... x Strophomena cf. hecuba Billings...... x Strophomena cf. rugilifera Wang...... x x ~~~-a~ ...... x Strophomenids...... x ? Thaerodonta sp...... x Zygospira cf. recurvirostris aequivalvis Twenhofel x Zygospira cf. paupera Billings ...... x Hormotoma sp...... x Lophospira spp...... x x Gastropods...... x x Orthoconic cephalopods ...... x x Grammysia sp...... x ? Pterinea sp...... x Pelecypods ...... x x Ostracods ...... x x x Crinoid ossicles...... x Scolecodonts...... x x "Arthrophycus" sp...... x The age of the Yeoman Beds and younger Ordovician Strata of Saskatchewan is discussed under (vi) Age of the Ordovician Strata (p. 19). (ii) HERALD BEDS FAUNA (Plate Ill) Clathrodictyon sp. Eofletcheria sp. Tabulate corals (2 spp.) Fenestellid Bryozoa Megamyonia cf. unicostata (Meek and Worthen) Orthid Strophomena cf. rugilifera Wang ? Thaerodonta sp. Small orthoconic cephalopod ? Pterinea sp. Pelecypods Ostracods Crinoid ossicles Scolecodonts 16 The occurrences of Megamyonia unicostata and Strophomena rugilifera in surrounding areas were discussed under the Yeoman Beds, together with the correlations of the Red River Beds as a whole. Species of Clathrodictyon are cosmopolitan in rocks of Cambrian to Devonian age. Eofl etcheria occurs in strata of Ordovician age in North America. A species of Thaerodonta occurs in the Red River formation of eastern Montana. Pterinea has a wide distribution in rocks of Ordovician to Pennsylvanian age. Ross (1957 ) records "Pterinea?" in the Stony Mountain Shale member in the subsurface of eastern Montana. (iii ) STOUGHTON BEDS FAUNA (Plates IV and V ) Streptelasma trilobatum Whiteaves Batastoma sp. Catazyga sp. Diceromyonia cf. ignota (Sardeson ) Diceromyonia cf. storeya Okulitch ? Diceromyonia Dinorthis (? "Pionorthis") cf. occidentalis Okulitch Lepidocyclus cf. gigas Wang Megamyonia cf. ceres (Billings) Megamyonia cf. nitens (Billings ) Megamyonia cf. unicostata (Meek and Worthen) M.~gamyonia cf. M. sp. Wang (1949, pl. 9, Fig. C) ? Opikina cf. limbrata Wang Orthid Strophomena hecuba Billings Zygospira cf. recurvirostris aequivalvis Twenhofel Scolecodonts All the above fossils came from the Stony Mountain Shale member. No identifiable fossils were recovered from the more purely calcareous facies of the Stoughton Beds. Streptelasma trilobatum occurs in the Stony Mountain formation in Manitoba and Montana, and in correlative shaly beds near the top of the Bighorn dolomite in Wyoming. A species of Batastoma occurs in the lower shale member of the Stony Mountain formation in Eastern Mon tana, and B. manitobense Ulrich is recorded from the Stony Mountain 1 Shale and /or Penitentary members of the Manitoba outcrops • Species of Catazyga are common in Upper Ordovician (Richmond ) strata in eastern North America. A species of Diceromyonia comparable with D. ignota, D. storeya, a Dinorthis (?"Pionorthis") comparable with D. (?"P.") storeya Okulitch, Lepidocyclus gigas, a species of Megamyonia near M. nitens, a species of? bpikina near? b. limbrata, and Strophomena hecuba, all occur in red shaly beds in the uppermost part of the Bighorn dolomite in northeast Wyoming, which appear to be the undoubted lateral equivalent of the Stony Mountain shale member of the Williston Basin in eastern Montana, the two having almost identical faunas (Ross, 1957 ). A Megamyonia near M. nitens, a species of? Opikina near ? 6. limbrata, and Strophomena hecuba also occur in the shale member of the Stony Mountain formation in the subsurface of eastern Montana, as do 1 Baillie (1952) does not differentiate between occurrences of fossils in the calcareous shales of the Stony Mountain Shale member and the shaly dolomites of the Penitentary member, the two being grouped together for the purpose of recording the fauna. 17 three other species of Megamyonia, one comparable with M. unicostata, one with M. ceres, and a third comparable with M. sp. of Wang, 1949 (pl. 9, Fig. C). Megamyonia cf. ceres is also recorded from the lower beds of the upper (? Leigh) member of the Bighorn dolomite of Wyoming. Baillie (1952) records Diceromyonia ? storeya in the Stony Mountain shale and/ or Penitentary members of the outcrop areas of Manitoba, together with Dinorthis (Plaesiomys ) occidentalis Okulitch, Megamyonia nitens and a species of Lepidocyclus. A species of Zygospira comparable with Z. recurvirostris aequivalvis is recorded by Ross (1957) in the Red River formation of eastern Montana and a species of the Z. recurvirostris type occurs in the red, shaly, beds of the uppermost Bighorn dolomite, referred to above. The fauna of the Stony Mountain Shale member of the Stoughton Beds in the subsurface of Saskatchewan reinforces the previously pro, posed correlation between these Beds and the combined Stony Mountain Shale and Penitentary members of the Manitoba outcrops, which occupy a similar stratigraphic position, and which have a similar lithology and combined thickness (Porter and Fuller, 1959). Correlation with Ross's Stony Mountain shale member of the subsurface of eastern Montana, and with the shaly part of the upper part of the Bighorn dolomite of northeast Wyoming (Ross, 1957 ) also appears certain. Ross's correlation of the latter with the former appears reconfirmed. (iv) GuNTON BEDS The only fossils recovered from the Gunton Beds were immature, poorly preserved streptelasmids (Plate V ). (v ) STONEWALL BEDS FAUNA (Plate VI ) Above t marker horizon: Streptelasmid Favosites cf. Javosus Goldfuss Favositid Syringopora sp. Hallopora sp. Bryozoan Below t marker horizon: Halysites ( Catenipora) gracilis Hall ? Opikina stonewallensis Stearn Halysites ( Catenipora ) gracilis is a common fossil in upper Ordovician rocks from Baffin and Quebec to Wyoming and Idaho. Corals of this type occur in the Red River formation in Manitoba a!1d eastern Montana. Abundant specimens of? bpikina stonewallensis reinforce the correlation previously proposed (Porter and Fuller, 1959 ) between the lower part of the Stonewall Beds of the Williston basin and the lower part of the Stonewall formation of the Manitoba outcrops, where this fossil is com, mon. bpikina is not known in rocks younger than Upper Ordovician. The fauna recovered from strata above the t marker suggest a Silurian age for this part of the Stonewall Beds. Favositids of Favosites javosus 1 type are found in Lower and Middle Silurian strata at many localities in eastern North America. Syringopora 2 is not known in strata older than Silurian. 1, 2 Favosites cf.javosus and Syringopora sp. referred to here appear in Porter and Fuller (1959, p. 156) as Favosites sp., and Halysites sp. Further sectioning has enabled a closer, and a different, identification to be made (Plate VI, Fig. 6). 18 Hallopora ranges from Ordovician to Devonian. From the rather slender fauna! evidence available here it appears that the Ordovician;Silurian boundary may coincide with the prominent t marker within the Stonewall formation (Fig. 3 ). Porter and Fuller (1959) appear to have suspected this possibility. They say (p. 178 ): "It is important to note that the fauna from the type section seems to have been collected from levels below the mid;Stonewall non;sequential bed (horizon t ); the upper beds are not exposed at Stonewall. For pur; poses of clarity the entire formation is arbitrarily classed in this paper . .. as Ordovician." (vi ) AcE OF THE 0Roov1c1AN STRATA The Red River and Stony Mountain Beds, and the Stonewall Beds below the t marker, appear to be of Upper Ordovician (Cincinnatian) age (Baillie, 1952; Ross, 1957; Porter and Fuller, 1959). Fossils from these strata in Saskatchewan unfortunately offer no greater assistance than fossils recovered from these intervals in other localities, in more exactly dating the strata. The Stony Mountain and the Stonewall Beds below the t marker seem to be of Richmondian age, and at least the upper part of the Red River Beds may also be of Richmondian age. If further palaeontological evidence comes to light in support of the suggestion made here that the t marker within the Stonewall Beds may coincide, at least approximately, with the Ordovician;Silurian boundary, division of the Stonewall Beds at the t marker into two named units will become necessary, to avoid a situation where a stratigraphic unit straddles a discernible systemic boundary. B. SILURIAN (i ) RUPERT BEDS FAUNA (Plates VI and VII ) Above u marker horizon: Clathrodictyon Jastigiatum Nicholson Brachyprion cf. paskoiacensis Stearn Fardenia cf. elegans (Prouty) Fardenia ellipsoides Stearn Lophospira sp. Gastropods Ostracods Below u marker horizon: Palaeofavosite s poulseni Teichert Palaeojavosites poulseni is typical of the Stonewall and Fisher Branch formations of the Manitoba outcrops (Fig. 3 ) and ranges up to the In; wood formation. Clathrodictyon jastigiatum occurs at the top of the East Arm dolomite and in the Chemahawin member of the Cedar Lake formation in Mani; toba. Brachyprion paskoiacensis is recorded from the Fisher Branch and Inwood formations, and Fardenia elegans from the Moose Lake dolomite (with doubtful specimens from the Inwood formation) of the Manitoba outcrops. In the same area Fardenia ellipsoides ranges from the Inwood formation to the Akitameg dolomite. Lophospira occurs in both Ordo; vician and Silurian strata in North America. 19 The correlation proposed by Porter and Fuller (1959) of the Rupert (Lower Interlake) Beds of the subsurface with the combined Fisher Bra nch sJolomite, Inwood formation, Moose Lake dolomite and Atikameg dolomite of the outcrop areas of Manitoba is supported by the constitu, tion of this fauna, especially when the fauna of the overlying Hanson Beds is considered. However, taking into account the number of Inwood formation fossils found above the u marker, and the nature and prom, inence of the marker; the writer would be more inclined to correlate the u marker with the sandy and silty dolomites at the base of Baillie's Unit D (Baillie, 1951 ) (within the Inwood formation ) rather than with the lesser development of silty and argillaceous strata at the top of the Jn, wood formation (Baillie, 195 1; Stearn, 1956; Fuller and Porter, 1959, Fig. 4 ), thus correlating the upper beds of the Inwood formation with the lowest strata of the Rupert Beds above the u marker (Fig. 3 ). The age of the rocks of the Interlake Group is dealt with under (vi) Age of the Silurian Strata, (p. 22 ). (ii ) HANSON BEDS FAUNA (Plates VII and VIII ) Above w marker horizon: Favosites gothlandicus Lamarck Favosites niagarensis Hall ? Fardenia sp. Hormotoma sp. Lophospira sp. Ostracods Below w marker horizon : Clathrodictyon jastigiatum Nicholson Clathrodictyon cf. regulare Rosen Clathrodictyon cf. striatellum (D'Orbigny ) Clathrodictyon sp. Labechiella sp. Stromatoporella sp. S troma toporoid Dinophyllum hindi (Stearn) Favosites cf. gothlandicus Lamarck Favosites niagarensis lundarensis Stearn Palaeojavosites poulseni Teichert Palaeojavosites cf. transiens Stearn Brachyprion cf. inflatus Stearn Brachyprion paskoiacensis Stearn Brachyprion philomena (Billings) Camarotoechia cf. indianensis (Hall ) Clintonella bailliei Stearn Rhipidomella cf. uberis (Billings) Zygospira cf. paupera Billings Orthoconic cephalopod Grammysia sp. "Arthrophycus" sp. Clathrodictyon Jastigiatum occurs at the top of the East Arm dolomite and in the Chemahawin member of the Cedar Lake formation in the Manitoba outcrops. In the same area, Clathrodictyon cf. regulare is recorded from the top of the Cedar Lake formation, and Clathrodictyon striatellum occurs in the Cross Lake member of the Cedar Lake forma, tion. The genus Clathrodictyon ranges from Cambrian to Devonian, 20 Labechiella occurs in Silurian and Devonian strata, and Stromatoporella ranges from Silurian to Carboniferous. Dinophyllum hindi ranges from the Stonewall to the Inwood formation in Manitoba. Favosites gothlandicus ranges throughout the Interlake group in the Manitoba outcrops. Forms of F. niagarensis are confined to the Cedar Lake formation. Palaeojavosites transiens ranges from the Fisher Branch dolomite to the Cedar Lake dolomite in the Manitoba outcrops. It is most abundant in the Cross Lake member of the Cedar Lake dolomite. In the same area P. poulseni occurs in the Fisher Branch and Inwood for, mations. In the Manitoba outcrops Brachyprion inflatus occurs in the Cross Lake member of the Cedar Lake formation; B. paskoiacensis in the Fisher Branch, Inwood and Moose Lake units, and B. philomena in the Fisher Branch and Inwood formations. Camarotoechia indianensis is recorded from the Fisher Branch dolomite, Inwood formation, Moose Lake dolo, mite and Cedar Lake formation, and Clintonella bailliei occurs in the East Arm dolomite and the Cross Lake member of the Cedar Lake formation. The genus Fardenia is typical of Middle Silurian strata in many parts of North America. It ranges into Upper Silurian strata. Rhipidomella uberis occurs in both Silurian and Ordovician rocks in Anticosti Island. Zygos, pira paupera occurs only in Silurian strata in the same area. Hormotoma and Lophospira both occur in Ordovician and Silurian strata elsewhere in North America. Grammysia ranges from Silurian to Mississippian. The problematical "Arthrophycus" is common in Lower Silurian rocks in eastern North America. The type recovered here, though poorly preserved, seems to differ slightly from previously recorded figured examples available to the writer. The above fauna contains forms previously recorded from strata ranging between the Fisher Branch dolomite and the Cedar Lake forma, tion of the Manitoba outcrops. In spite of this, the writer feels that the correlation proposed by Porter and Fuller (1959) of the Hanson (Middle Interlake) Beds below their unnamed marker horizon (the w marker of this report) with the East Arm dolomite and the lowermost part of the Cedar Lake formation, and of the Hanson Beds above this marker, in part, with the Cedar Lake formation is correct. In the area of the Manitoba outcrops the richly fossiliferous Inwood formation is succeeded by two units, the Moose Lake and Akitameg dolomites, which, due to changes in sedimentary conditions, have rela, tively impoverished faunas, brachiopods being particularly affected. Taking into account the greatly decreased chance of obtaining a large collection of fossils from a few well cores, no such impoverishment seems to take place in Saskatchewan, and certain fossils (Dinophyllum hindi, Palaeojavosites poulseni, Brachyprion paskoiacensis, and B. Philomena ) persist into strata which appear to be younger than those in which they occur in Manitoba. Clathrodictyon jastigiatum, Favosites gothlandicus, Palaeojavosites transiens, Camarotoechia indianensis, and Clintonella bailliei either occur in the East Arm dolomite in Manitoba, or else are recorded from strata both above and beneath the unit. A Clathrodictyon comparable with C. regulare, C. striatellum, Favosites niagarensis lundarensis, and Brachyprion injlatus all occur in the Cedar Lake formation of Manitoba. 21 The lower division of the Hanson Beds of the subsurface of Sask; atchewan, i.e., strata of the Hanson Beds below the w marker, appear to correlate with the East Arm dolomite plus an indeterminate thickness of strata at the base of the Cedar Lake formation of the Manitoba out, crops. The two tabulate corals obtained from the Hanson Beds above the w marker both occur in the Cedar Lake formation of Manitoba. The ratio of thickness of the Hanson Beds above the w marker to the Cedar Lake formation (including even the lowest beds, some of which appear to correlate with the upper part of the Hanson Beds below the marker), some 2 or 2! to I, suggests that strata may be present in the upper Hanson Beds laterally equivalent to strata younger than the Cedar Lake formation which have been removed by erosion in Manitoba. (iii ) RISSER BEDS FAUNA Stromatoporella cf. constellata Hall Stearn (1956) records Stromatoporella cf. constellata from the Chema; hawin member of the Cedar Lake formation of M anitoba. The Risser Beds are probably younger than any Silurian strata outcropping in Manitoba. (iv ) ACE OF THE SILURIAN STRATA Stearn (1956) believes the lowest rocks of the Interlake group of Manitoba to be of Middle Silurian age. Porter and Fuller (1959 ) have summarized the lack of fauna! evidence for this in the Manitoba outcrop areas, and cite the lack of any evidence in the regional sedimentation pattern as further proof against any Lower Silurian "gap" in sedimenta, tion. Concerning the Stonewall;Interlake Boundary, Porter and Fuller ( 1959 ) write: "The sedimentation break at the junction is no greater than the others (e.g., p, top Gunton, t, u, v, mid, and top, Middle Inter, lake) found in the Bighorn and Interlake groups." This argument applies, too, to the junction of the Stonewall Beds above the t marker and those below this marker, which the writer believes may be the Ordovician, Silurian boundary in this area. There is no evidence of angular uncon; formity or of strata being removed at any of the sedimentation breaks within the Ordovician and Silurian succession of carbonate rocks in this area. The Lower Silurian (Medinan )-Middle Silurian (Niagaran ) boun; dary has been provisionally placed at the u marker of the Rupert Beds, above which the fauna becomes richer and shows affinities with that of overlying strata. Thus it appears that this boundary may occur within the Inwood formation of the Manitoba outcrops. Upper Silurian strata may be present in the Risser Beds, but at the present time palaeontolo; gical evidence for or against this is lacking. 22 BIBLIOGRAPHY Andrichuk, J. M. 1959: Ordovician and Silurian Stratigraphy and Sedimentation in Southern Manitoba, Canada; Amer. Assoc. Petrol. Geo/. , Bull., vol. 43, No. 10, pp. 2333-2398. Baillie, A. D. 195 I : Silurian Geology of the Interlake Area, Manitoba; Province of Manitoba, Mines Branch, Publ. 50-1. 1952: Ordovician Geology of Lake Winnipeg and Adjacent Areas, Manitoba; Province of Manitoba, Mines Branch, Publ. 51-6. Brindle, J. E. 1960: Mississippian Megafaunas in Southeastern Saskatchewan; Province of Saska tchewan, Department of Mineral Resources, Report No. 45. Cumming, A. 0:, Fuller, J. G. C. M., and Porter, J. W. 1959: Separation of Strata: Palaeozoic Limestones of the Williston Basin ; Amer. } our. Sci., vol. 257, No. 10, pp. 722,733. Duncan, H . 1956: Ordovician and Silurian Coral Faunas of Western United States; U.S. Geo/. Surv., Bull. 1021-F, pp. 209-236, pis. 21,27. Fuller, J. G. C. M . 1956: Mississippian Rocks and Oilfields in Southeastern Saskatchewan; Province of Saskatchewan, Department of Mineral Resources, Report No. 19. Kent, 0 . M . 1960: The Evaporites of the Upper Ordovician Strata in the Northern Part of the Williston Basin; Province of Saskatchewan, Department of Mineral Re sources, Report No. 46. Kupsch, W. 0. 1953 : Ordovician and Silurian stra tigraphy of east-central Saskatchewan ; Province of Saskatchewan, Department of Mineral Resources, Report No. 10. Moore, R . C. (Director and Editor) 1953: Treatise on Invertebrate Paleontology, Part G, Bryozoa; Geo/. Soc. Amer. and Univ. Kansas Press, Lawrence, Kansas. 1956: Treatise on Invertebrate Paleontology, Part F, Coelenterata; Geo/. Soc. Amer. and Univ. K ansas Press, Lawrence, Kansas. Porter, J. W., and Fuller, J. G. C. M . 1959: Lower Paleozoic Rocks of Northern Williston Basin and Adjacent Areas; Amer. Assoc. Petrol. Geo/., Bull., vol. 43, No. I, pp. 124, 189. Ross, R. J. 1957: Ordovician Fossils From Well s in the Williston Basin Eastern Montana; U.S. Geo/. Surv., Bull. 1021, M, pp. 439,510, pis. 37-43. Saskatchewan Geological Society 1956: Report of the Mississippian Names and Correlations Committee. 1958: Report of the Lower Palaeozoic Names and Correlations Committee. Sinclair, G. W. 1959: Succession of Ordovician Rocks in Southern Manitoba; Geo/. Surv. Canada, Paper 59,5. Sinclair, G. W., and Leith, E. I. 1958: New name fo r an Ordovician Shale in Manitoba; } our. Pa/eont., vol. 32, No. l, pp. 243-4. Stearn, C . W. 1956: Stratigraphy and Palaeontology of the Interlake Group a nd Stonewall Formation of Southern Manitoba; Geo/. Surv. Canada, Mem. 281 . Twenhofel, W. H . 1928: Geology of Anticosti Island; Geo/. Surv. Canada, Mem. 154. Wang, Y. 1949: Maquoketa Brachiopoda of Iowa; Geo/. Soc. Amer., Mem. 42. 23 APPENDIX FAUNAS FROM SELECTED 1 WELLS Tidewater ALLAN CROWN No. l Lsd 4,I0,33,lw3 Elev. K.B. 1762' Depth in feet YEOMAN BEDS 4831 Small streptelasmid 4847.5 Fragment large streptelasmid 4876 Nyctopora sp. Imperial ARM RIVER ANNANDALE No. 6,23 Lsd 6,23,8,32wl Elev. K.B. 1980.7' Depth in feet HERALD BEDS 6356 Strophomena cf. rugilijera Wang California Standard BANNOCK No. 15,5 Lsd 15,5,46,9w2 Elev. K.B. 1725' Depth in feet HANSON BEDS 2010, 2011 Ciathrodictyon jastigiatum Nicholson, Clathrodictyon cf. regulare Rosen, Clathrodictyon cf. stria, tellum (D'Orbigny), Favosites niagarensis lundarensis Stearn, Brachyprion cf. inflatus Stearn California Standard,Tidewater CARNOUSTIE PROVINCE No. 4,20 Lsd 4,20,17,32wl Elev. K.B. 1791' Depth in feet HERALD BEDS 4626.5 Clathrodictyon sp. 4637.5 Orthoconic cephalopod (small) 4638.5 Scolecodont 4640 ? Pterinea sp., ostracods lmperial,Tidewater CLIMAX No. 6,10 Lsd 6,10,3,18w3 Elev. K.B. 3076' Depth in feet HANSON BEDS 6906.25 Stromatoporella sp. 6914.5 Stromatoporella sp. 6914.75 Labechiella sp. 6916 Clathrodictyon sp. 6916.5 Palaeojavosites poulseni Teichert 6918 Palaeojavosites poulseni Teichert HERALD BEDS 7127.5 Streptelasma cf. latusculum (Billings ) Imperial CONSTANCE No. 8,36 Lsd 8,36,3,29w2 Elev. K.B. 2844' Depth in feet RUPERT BEDS 8245 Lophospira sp. I Wells with cores containing fossils not identifiable as to genus have been omitted. Depths are to nearest qua rter-foot . 24 8263.5 Fardenia ellipsoides Stearn 8268.5 Ostracods 8269.5 Fardenia ellipsoides Stearn 8272 Fardenia ellipsoides Stearn, ostracods 8273 Brachyprion paskoiacensis Stearn 8273.75 Brachyprion paskoiacensis Stearn 8292.5 Fardenia cf. elegans (Prouty) 8294 Immature brachiopods, immature gastropods, orthoconic cephalopod YEOMAN BEDS 8642.5 Gastropods, ostracods 8699 ? Rosenella sp. 8713 Streptelasma cf. latusculum (Billings ) DUNDURN CROWN No. 2 Lsd 8-17-32-5w3 Elev. K.B. 1725' Depth in feet YEOMAN BEDS 4940 Megamyonia sp., strophomenid 4984 ? Holtedahlina sp. Imperial-California Standard FORT A LA CORNE No. 8-9 Lsd 8-9-50-18w2 Elev. K.B. 1433.46' Depth in feet HANSON BEDS 1586.5 Clathrodictyon jastigiatum Nicholson Imperial GUERNSEY No. 13-34 Lsd l3-34-33-23w2 Elev. K.B. 1791.4' Depth in fee t HANSON BEDS 3978.5 Fauosites gothlandicus Lamarck RUPERT BEDS 4186 Ostracods 4217.5 Ostracods Imperial HARTAVEN No. 2-11 Lsd 2-1 1-10-9w2 Elev. K.B. 2054' Depth in fee t STOUGHTON BEDS 7436.5 Scolecodonts 7442 Diceromyonia cf. ignota (Sardeson ), Strophomena hecuba Billings 7450 ? Diceromyonia sp. 7454.5 Megamyonia cf. M. sp. Wang, 1949, pl. 9, Fig. C 7455.25 Megamyonia cf. M . sp. Wang, 1949, Pl. 9, Fig. C 7465 Lepidocyclus cf. gigas Wang, Megamyonia cf. ceres (Bill ings), Strophomena hecuba Billings 7471 Megamyonia cf. M . sp. Wang, 1949, pl. 9, Fig. C 7486.5 Zygospira cf. recuruirostris aequivalvis Twenhofel 7488 Megamyonia cf. unicostata (Meek and Worthen ), Zygospira cf. recuruirostris aequivalvis Twenhofel HERALD BEDS 7494 Ostracods 7494.5 Ostracods 25 7522 Tabulate corals (2 spp. ), bryozoa, ? Thaerodonta sp., brachiopod fragments, crinoid ossicles, scolecodonts 7525 Eofletcheria sp. 7526 Eofletcheria sp. 7530.5 Strophomena cf. rugilifera Wang 7532 Orth id Imperial HERALD No. 1,31 Lsd !,31,l,20w2 Elev. K.B. 2276' Depth in feet RISSER BEDS 8883 Stromatopora cf. constellata Hall STONEWALL BEDS 9327 Streptelasmid 9347 Favosites cf. javosus Goldfuss, Syringopora sp., bryozoan 9348.5 Favositid 9349 Hallopora sp. 9371 ?Opikina stonewallensis Stearn 9372 ?Opikina stonewallensis Stearn 9372.5 ?Opikina stonewallensis Stearn 9373 ?Opikina stonewallensis Stearn 9394.5 Halysites ( C Sohio-Canadian Devonian STONEY BEACH No. Lsd 4-16-18-23w2 Elev. K.B. 1918' 27 Depth in feet HANSON BEDS 5756 ? Fardenia sp. Fina WHITESWAN No. 11,7 Lsd 11-7-58-21w2 Elev. K.B. 1978' Depth in feet RUPERT BEDS 1338.5 Palaeojavosites poulseni Teichert 1340 Palaeojavosites poulseni Teichert Sohio,Standard WOOD MOUNTAIN No. 1 Lsd 16-10-4-4w2 Elev. K.B. 3115' Depth in feet HANSON BEDS 7925.5 Stromatoporoid 7936.5 Rhipidomella cf. uberis (Billings ), Grammysia sp. 7983.5 Orthoconic cephalopod ZENON PARK No. 1 Lsd l, 10,47-13w2 Elev. K.B. 1274' Depth in feet RUPERT BEDS 1660 Clathrodictyon Jastigiatum Nicholson 28 PLATES 1-Vm PLATE 1 YEOMAN BEDS Figures 1-2. Grewingkia cf. robusta (Whiteaves ), Imperial, Hummingbird No. 6-13 well, 9991 ft., xl. Figures 3-4. Streptelasma cf. goniophylloides Teichert, Imperial, Hum, mingbird No. 6-13 well, 9984 ft., x I. Figure 5. Streptelasma cf. latusculum (Billings), Imperial, Constance No. 8-36 well, 8713 ft., xl. Figure 6. Nyctopora sp., Tidewater, Allan Crown No. 1 well, 4876 ft., x2. Figure 7. Monticulipora cf. mammulata D 'Orbigny, Imperial, Hum, mingbird No. 6-13 well, 9882 ft., x I. Figure 8. ? Holtedahlina sp., Dundurn Crown No. 2 well, 4984 ft., x2. 30 PLATE I 8 x2 31 PLATE II YEOMAN BEDS Figures 1,3. Megamyonia cf. unicostata (Meek and Worthen), Imperial, Herald No. 1,31 well, 9664 ft., x I. Figure 4. Megamyonia sp., Dundurn Crown No. 2 well, 4940 ft., xi. Figures 5,6. Strophomena cf. hecuba Billings, Imperial, Hummingbird No. 6, 13 well, 9900.5 ft., x I. 32 PLATE II 6 3 33 PLATE III HERALD BEDS Figure 1. Clathrodictyon sp., California Standard-Tidewater, Car noustie Province No. 4-20 well, 4626.5 ft., x I. Figure 2. Streptelasma cf. latusculum (Billings ), Imperial,Tidewater, Climax No. 6-10 well, 7127.5 ft., xi. Figure 3. Megamyonia cf. unicostata (Meek and Worthen ), Canadian Devonian-Tidewater, Rupert No. 15-28 well, 6266 ft., xi. Figure 4. Strophomena cf. rugilifera Wang, Imperial, Arm River Ann, andale No. 6,23 well, 6356 ft., xi. J Figure 5. Strophomena cf. rugilifera Wang, Imperial Hartaven No. 2-11 well, 7530.5 ft., x I. Figure 6. Strophomena cf. rugilifera Wang, Canadian Devonian-Tide water, Rupert No. 15-28 well, 6282 ft., xi. Figure 7. ? Pterinea sp., California Standard-Tidewater, Carnoustie Province No. 4-20 well, 4640 ft., xi. 34 PLATE Ill 35 PLATE IV STOUGHTON BEDS (Stony Mountain Shale Member) Figures 1-2. Streptelasma trilobatum Whiteaves, Canadian Devonian, Tidewater, Rupert No. 15-28 well, 6249.5 ft., xl. Figure 3. Batastoma sp., Canadian Devonian-Tidewater, Rupert No. 15,28 well, 6243.75 ft., x 1. Figure 4. Catazyga sp., Canadian Devonian-Tidewater, Rupert No. 15-28 well, 6245.5 ft., xl. Figure 5. Diceromyonia cf. ignota (Sardeson), Canadian Devonian Tidewater, Rupert No. 15,28 well, 6249.5 ft., x2. Figure 6. Diceromyonia cf. storeya Okulitch, Canadian Devonian, Tidewater, Rupert No. 15-28 well, 6258.25 ft., xl. Figure 7. Dinorthis (."Pionorthis" ) cf. occidentalis Okulitch, Canadian Devonian,Tidewater, Rupert No. 15-28 well, 6258 ft., x I. Figure 8. Lepidocyclus cf. gigas Wang, Imperial, Hartaven No. 2-11 well, 7465 ft., xl. Figure 9. Lepidocyclus cf. gigas Wang, Canadian Devonian,Tide, water, Rupert No. 15-28 well, 6260 ft., xl. Figure IO. Megamyonia cf. ceres (Billings), Imperial Hartaven No. 2-11 well, 7465 ft., xl. Figure 11. Megamyonia cf. ceres (Billings ), Canadian Devonian,Tide, water, Rupert No. 15-28 well, 6243 ft., xl. Figure 12. Megamyonia cf. ceres (Billings), Canadian Devonian,Tide, water, Rupert No. 15-28 well, 6256 ft., xl. Figure 13. Megamyonia cf. nitens (Billings ), Canadian Devonian Tidewater, Rupert No. 15-28 well, 6247.5 ft., xl. Figure 14. Megamyonia cf. unicostata (Meek and Worthen), Imperial Hartaven No. 2-11 well, 7488 ft., xl. Figure 15. Megamyonia cf. unicostata (Meek and Worthen), Canadian Devonian-Tidewater, Rupert No. 15,28 well, 6256 ft., xl. Figure 16. Megamyonia cf. unicostata (Meek and Worthen), Canadian Devonian,Tidewater, Rupert No. 15,28 well, 6263.5 ft., x 1. Figure 17. Megamyonia cf. unicostata (Meek and Worthen), Canadian Devonian-Tidewater, Rupert No. 15-28 well, 6264.5 ft., x I. 36 PLATE IV 6 7 8 9 10 II 12 15 16 -'~i,···[l;M", -, r..l!'r. r -:WIIIBf.,""\: -~ 4. ! ·- • • ,, ,ff !/ ~"• :._ ~L 't. L. ..~ 17 13 37 PLATE V STOUGHTON BEDS (Stony Mountain Shale Member) Figure I. Megamyonia cf. M. sp. Wang (1949, pl. 9., Fig. C ), Im, perial, Hartaven No. 2-11 well, 7455.25 ft., xl. Figure 2. Megamyonia cf. M . sp. Wang (1949, pl. 9., Fig. C ), Imperial Hartaven No. 2,11 well, 7471 ft., xl. Figure 3. ? 6pikina cf. limbrata Wang, Canadian Devonian,Tidewater Rupert No. 15,28 well, 6264.5 ft., xi. Figure 4. Strophomena hecuba Billings, Imperial, Hartaven, No. 2-11 well, 7442 ft., xl. Figure 5. Strophomena hecuba Billings, Imperial, Hartaven No. 2, 11 well, 7465 ft., xi. Figure 6. Zygospira cf. recuruirostris aequivalvis Twenhofel, Imperial, Hartaven No. 2-11 well, 7486.5 ft., x2. Figure 7. Zygospira cf. recurvirostris aequiualvis Twenhofel, Canadian Devonian-Tidewater, Rupert No. 15,28 well, 6250 ft., x3. Figure 8. Zygospira cf. recuruirostris aequivalvis Twenhofel, Canadian Devonian-Tidewater, Rupert No. 15-28 well, 6253 ft., x2. Figure 9. Zygospira cf. recuruirostris aequivalvis Twenhofel, Canadian Devonian-Tidewater, Rupert No. 15,28 well, 6253.25 ft., xl. GUNTON BEDS Figure 10. Immature streptelasmid, British American, Quinn No. 9,34X well, 8458 ft., xl. 38 PLATE V 39 PLATE VI STONE WALL BEDS Figure 1. Halysites ( Catenipora ) gracilis Hall, Imperial, Herald No. 1-31 well, 9394.5 ft., x l. Figure 2. ? Opikina stonewallensis Stearn, Imperial, Herald No. 1-31 well, 9372 ft., xl. · Figure 3. ? bpikina stonewallensis Stearn, Imperial, Herald No. 1-31 well, 9372.5 ft., x l. Figure 4. ? bpikina stonewallensis Stearn, Imperial, Herald No. 1-31 well, 9373 ft., xl. Figure 5. ? bpikina stonewallensis Stearn, Imperial, Herald No. 1-31 well, 9397.5 ft., xl. Figure 6. Favosites cf. Javosus Goldfuss, Syringopora sp., bryozoan, Imperial, Herald No. 1-31 well, 9347 ft., x l. RUPERT BEDS Figure 7. Palaeojavosites poulseni Teichert, Fina, Whiteswan No. 11-17 well, 1338.5 ft., xl. Figure 8. Fardenia cf. elegans (Prouty), Imperial, Constance No. 8,36 well, 8292.5 ft., x2. 40 PLATE VI 41 PLATE VII RUPERT BEDS Figure 1. Fardenia ellipsoides Stearn, Imperial, Constance No. 8-36 well. 8263.5 ft., xl. Figure 2. Fardenia ellipsoides Stearn, Imperial, Constance No. 8-36 well, 8269.5 ft., xl. Figure 3. Fardenia ellipsoides Stearn, Imperial, Constance No. 8-36 well, 8272 ft., x I. HANSON BEDS Figure 4. Clathrodictyon· Jastigiatum Nicholson, Imperial-California Standard, Fort a la Corne No. 8-9 well, 1586.5 ft., x2. Figure 5. Clathrodictyon sp., Imperial,Tidewater, Climax No. 6-10 well, 6916 ft., xl. Figure 6. Stromatoporella sp., Imperial-Tidewater, Climax No. 6-10 well, 6906.25 ft., x2. Figure 7. Favosites niagarensis lundarensis Stearn, California Stand ard, Bannock No. 15-5 well, 2010-2011 ft. interval, x2. Figure 8. Palaeojavosites cf. transiens Stearn, Sohio,Standard, Pense No. 1 well, 5990 ft., x2. Figure 9. Palaeofavosites poulseni Teichert, Imperial-Tidewater, Cli max No. 6-10 well, 6916.5 ft., x I. Figure 10. Brachyprion cf. inflatus Stearn, California Standard, Bann ock No. 15-5 well, 2010-2011 ft. interval, xl. Figure 11. Brachyprion paskoiacensis Stearn, Sohio-Standard, Pense No. 1 well, 5990 ft., xl. 42 PLATE VII 43 PLATE VIII HANSON BEDS Figure I. Brachyprion philomena (Billings), Sohio,Standard, Pense I No. I well, 5988.5 ft., x I. 1 Figure 2. Clintonella bailliei Stearn, Sohio,Standard, Pense No. I well, 5993.5 ft., x2. Figure 3. Clintonella bailliei Stearn, Sohio,Standard, Pense No. 1 well, 5994.5 ft., x2. Figure 4. Rhipidomella cf. uberis (Billings ), Sohio,Standard, Wood Mountain No. 1 well, 7936.5 ft., xi. Figure 5. Zygospira cf. paupera Billings, Hudson's Bay Junction, No. 6 well, 1227 ft., x I. Figure 6. Grammysia sp., Sohio,Standard, Wood Mountain No. 1 well, 7936.5 ft., x I. Figure 7. " Arthrophycus" sp., Riddle, Tidewater, Rocanville No. 16,32 well, 4295.5 ft., xl. Figures 8,9. Favosites gothlandicus Lamarck, Imperial, Guernsey No. 13,34 well, 3978.5 ft., x I. Figure 10. Favosites niagarensis Hall, Riddle,Tidewater, Rocanville No. 16,32 well, 4205 ft., xi. Figure 11. ? Fardenia sp., Sohio,Canadian Devonian, Stoney Beach No. 1 well, 5756 ft., x I. 44 PLATE VIII x2 x2 3 2 45 RECINA, SASKATCHEWAN Printed by LAWRENCE AMON, Printer to the Queen's Most Excellent Majesty 1961 of.li',,~1