Age of the Bedford Shale, 

Berea Sandstone, and 

Simbury Shale in the 

Appalachian and Michigan Basins, 

Pennsylvania, Ohio, and Michigan

By WALLACE DE WITT, JR.

CONTRIBUTIONS TO STRATIGRAPHY

GEOLOGICAL SURVEY BULLETIN 1294-G
UNITED STATES DEPARTMENT OF THE INTERIOR 

WALTER J. HICKEL, Secretary

GEOLOGICAL SURVEY 

William T. Pecora, Director

U.S. GOVERNMENT PRINTING OFFICE 

WASHINGTON : 1970

For sale by the Superintendent of Documents, U.S. Government Printing Office 

Washington, D.C. 20402 - Price 10 cents (paper cover)
CONTENTS

	Page 

Abstract...-----_-_-_--____-_--____________--__-_-_-______________ Gl

Purpose.______-__-__-_-__----______-__________--___-_____________ 1

Acknowledgments. _________________________________________________ 2

Age and correlation in the Appalachian basin_________________________ 2

Age of units in the Michigan basin_________________________________ 10

Summary_ _ __________________________________________________ _ 10

References cited.__________________________________________________ 10

ILLUSTRATIONS

Page 

FIGURE 1. Schematic stratigraphic section from northern Ohio to central

Pennsylvania.________________________________________ G3

2. Chart showing age and correlation of stratigraphic units discussed in this report_______--------_------------------- 4

3. Index map showing localities mentioned in this report _____ 6

4. Map showing distribution of the Berea and Cussewago Sandstones in northeastern Ohio and northwestern Pennsylvania. _ 7

in

370-839 70

CONTRIBUTIONS TO STRATIGRAPHY

AGE OF THE BEDFORD SHALE, BEREA 

SANDSTONE, AND SUNBURY SHALE 

IN THE APPALACHIAN AND MICHIGAN BASINS, PENNSYLVANIA, OHIO, 

AND MICHIGAN

By WALLACE DE WITT, JR.

ABSTRACT

The suggestion by Sanford (1967, p. 994) that the Bedford Shale, Berea 

Sandstone, and Sunbury Shale of the Michigan basin are of Late Devonian age 

because these strata contain Hymenozonotriletes lepidophytus Kedo is invalid 

for these formations in the Appalachian basin, the area of their type localities. 

Endosporites lacunosus Winslow, a synonym of Hymenozonotriletes lepidophytus Kedo, occurs in upper Chautauqua (Upper Devonian) rocks through much 

of the Kinderhook (Lower Mississippian) strata in Ohio. The Sunbury Shale, 

the Sunbury Member of the Orangeville Shale in part of northern Ohio, contains a Siplionodella fauna which clearly demonstrates the Kinderhook age of 

the unit. The basal strata of the Bedford Shale contain Spathoffnathodus anteposlcornis which suggests a very Late Devonian or very Early Mississippian 

age for this part of the Bedford. Except for the basal fossil zone, most of the 

Bedford Shale and the younger Berea Sandstone overlie the Murrysville sand, 

which along the Allegheny Front in central Pennsylvania contains an Adiantites 

flora of Early Mississippian (Kinderhook) age. The presence of Adiantites in 

the Murrysville sand indicates that most of the Bedford Shale and all the 

Berea Sandstone are of Early Mississippian age. Lithostratigraphic evidence 

suggests that the Berea Sandstone of Ohio may be a temporal equivalent of 

the basal Beckville Member of the Pocono Formation of the Anthracite region 

of Pennsylvania.

The clearly demonstrable Kinderhook age of the Sunbury, Berea, and most 

of the Bedford in the Appalachian basin strongly indicates a similiar age for 

the same units in the Michigan basin.

PURPOSE

Sanford (1967, p. 994) reported Hymenozonotriletes lepidophytus 

Kedo in the Berea Sandstone and Sunbury Shale of the Michigan 

basin, and because of the presence of this spore he assigned a Late

Gi
G2 CONTRIBUTIONS TO STRATIGRAPHY

Devonian age to these formations as well as to the subjacent Bedford 

Shale. Shifting the three formations from the Mississippian to the 

Devonian in the Michigan basin requires a similar change in age of 

these units in the Appalachian basin where the type localities of the 

three formations are located. Because a Late Devonian age is incompatible with much of the stratigraphic data for the Bedford, Berea, 

and Sunbury (Pepper and others, 1954, p. 13; Hass, 1947, p. 133), I 

have attempted to review and synthesize much of the data on the age 

of these strata that have become available since Pepper and his associates published their comprehensive work on the Bedford Shale and 

Berea Sandstone in 1954. The purpose of this review is to determine 

as closely as possible the age of the three formations in the Appalachian basin and to extrapolate these data into the Michigan basin.

ACKNOWLEDGMENTS

I wish to thank George Y. Cohee, John W. Huddle, and James M. 

Schopf, who are of the U.S. Geological Survey, for reviewing this 

paper. Their helpful suggestions are gratefully acknowledged. I have 

relied heavily on J. M. Schopf for paleobotanical information and 

on J. W. Huddle for the ranges of specific conodonts.

AGE AND CORRELATION IN THE APPALACHIAN BASIN

In discussing palynologic data for the detailed stratigraphy of the 

Strunian (Tn la) of the Ardennes area, Streel (1966, p. 70) stated 

that Endosporites lacunosus Winslow was synonymous with Hymenozonotriletes lepidopJiytus Kedo. Winslow (1962, p. 45) found that in 

Ohio Endosporites lacunosus ranged from the base of the Cleveland 

Member of the Ohio Shale upward into the post-Sunbury part of the 

Orangeville Shale of the Cuyahoga Group (fig. 1). The spore is most 

abundant in the Bedford Shale and overlying Berea Sandstone and 

is much less abundant in collections from the strata above and below 

these two formations.

Conodont faunas in the Cleveland Member of the Ohio Shale show 

that it is of Late Devonian age (Hass, 1956, p. 23; Oliver and others, 

1967, p. 1007) and probably correlates with strata in the SpathognatJiodus costatus zone (to VI] in the upper part of the Famennian 

(Oliver and others, 1967, p. 1035). The Sunbury Shale, the basal 

member of the Orangeville Shale in parts of northern Ohio, contains 

an abundant Siphonodella fauna of Early Mississippian (Kinderhook) age (fig. 2) and appears to correlate with strata in the upper 

part ofTnlb and Tn 2a in the lower part of the Tournaisian (Mamet, 

1967, p. 1003). These faunal data show that in the northwestern part
North-central Ohio 

(Cuyahoga County)

Northeastern Ohio 

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Western Pennsylvania 

(Pittsburgh area)

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FIGURE 1. Schematic stratigraphic section from northern Ohio to central Penn

Hymenozonotriletes lepidophytus Kedo; S, range of Siphonode lla ; Sp, range 

of Triphyllopteris flora. Numbers refer to localities shown in figure 3.
G4 CONTRIBUTIONS TO STRATIGRAPHY

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AGE OF BEDFORD SHALE, BEREA SANDSTONE, SUNBTJRY SHALE G5

of the Appalachian basin Hymenozonotriletes lepidophytus Kedo 

spans the Devonian-Mississippian boundary; hence, the spore cannot 

be used to substantiate a Devonian age assignment for the Bedford,; 

Berea, or Sunbury.

Mamet (1967) reviewed many of the problems associated with the 

placement of the Devonian-Carboniferous systemic boundary in the 

rocks of the Ardennes area of southern Belgium and adjacent northeast France, including the relation of the Famennian-Tournaisian 

Series boundary to the systemic boundary and the uncertainties surrounding the age assignment of the Etroeungt Limestone. Although 

intercontinental correlations are less certain than those in the United 

States, the f aunal and floral data indicate that strata in the Ardennes 

area which correlate with the Hymenozonotriletes lepidophytus-bearing rocks of Ohio range from the upper part of the Famennian (to VI) 

of unquestioned Late Devonian age into the lower part of the Middle 

Tournaisian (Tn %a) , the lower part of the Gattendorfia zone of Early 

Carboniferous age.

In north-central Ohio (fig. 3) in the vicinity of Cleveland, Cuyahoga County, a zone in the basal few feet of the Bedford Shale contains, 

invertebrate fossils which are similar to the fauna of the Louisiana 

Limestone of the Mississippi Valley. The conodont Spathognathodus 

anteposicornis is present in the basal fossil zone of the Bedford Shale 

(Oliver and others, 1967, p. 1035) and has been reported from the 

Louisiana Limestone. Collinson and others (1967, p. 962) assigned the 

Louisiana to the latest Devonian and suggested that the top of the 

limestone marks the Devonian-Mississippian boundary in parts of the 

Mississippi Valley area. Gutschick and Moreman, however (1967), 

reviewed much of the paleontologic data that has been used for determining the Devonian-Mississippian boundary adjacent to the craton 

in the central part of the United States and concluded that the base 

of the Louisiana Limestone should be the base of the Mississippian in 

the Mississippi Valley area. By correlation with the fauna in the Louisiana Limestone, the basal fossil zone of the Bedford Shale may be 

either very Late Devonian or very Early Mississippian. Also, according to J. TV. Huddle (written commun., 1969), SpatJwgnathodus anteposicornis occurs above SipJionodella in England in the Avonian,, 

Lower Carboniferous (Ehodes and others, 1969, p. 222), and the 

species is probably not restricted to the latest Devonian conodont zone 

(upper Spathognathodus costatus zone).

Except for the basal fossil zone and a scattering of spores, the Bedford Shale is largely unfossiliferous in most of its extent in easternOhio, extreme northwestern Pennsylvania, and northeastern Kentucky. The overlying Berea Sandstone is similarly relatively unfossiliferous. A few fossils have been found in the Berea, but, in general,
CONTRIBUTIONS TO STRATIGRAPHY

ONTARIO

MICHIGAN

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WEST 

VIRGINIA

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EXPLANATION

6 

Locality

1. Cleveland, Cuyahoga County

2. Trumbull County

3. Pittsburgh

4. Johnstown

5. Horse Shoe Curve, Altoona

6. Southern Anthracite coal basin

7. Lewis County

50 100I

200 MILES

FIGURE 3. Localities mentioned in this report.

they are long-ranging nondiagnostic forms or are too fragmentary for 

specific identification. In contrast, the overlying Sunbury Shale contains a conodont zone, characterized by several species of Siphonodella, 

in its basal beds throughout a large area in the western part of the 

Appalachian basin. The several species of Siphonodella which occur 

abundantly in the basal zone of the Sunbury permit correlation of the 

Sunbury with the Hannibal Shale and other /SipfionodeUa-be&Ymg 

units in the Lower Mississippian strata of the Mississippi Valley area 

(Hass, 1947, p. 136; 1956, p. 25). The Sunbury Shale is clearly of 

Kinderhook age from its contained conodont fauna. In northern Ohio 

the main problem is to resolve the age and correlation of the relatively 

unfossiliferous strata between the fossil zone of possible very Late 

Devonian age in the base of the Bedford Shale and the zone of Early 

Mississippian conodonts of Kinderhook age in the basal part of the 

Sunbury Shale.

In parts of Ashtabula and Trumbull Counties in northeastern Ohio,
AGE OF BEDFORD SHALE, BEREA SANDSTONE, SUNBURY SHALE G7

the Bedford Shale and overlying Berea Sandstone overlap the western edge of the friable medium-grained Cussewago Sandstone (de 

Witt, 1951, pi. 2). The Bedford and Berea are present in the subsurface of northeastern Ohio and extreme northwestern Pennsylvania 

where they lie upon the Murrysville sand, the subsurface equivalent 

of the Cussewago Sandstone. W. H. Hass and I were unable to find 

the basal fossil zone of the Bedford in northeastern Ohio; therefore, I 

conclude that the basal strata of the Bedford Shale in Trumbull and 

Ashtabula Counties are probably slightly younger than the basal fossiliferous zone in the formation at its type area south of Cleveland in 

Cuyahoga County, Ohio. Although pre-Berea erosion appears to have 

removed much of the Bedford Shale in parts of western Pennsylvania 

(Pepper and others, 1954, p. 60), the Berea Sandstone is recognizable 

above the Murrysville sand in the area as far east as the western part 

of Allegheny County, west of Pittsburgh (fig. 4).

EXPLANATION

Area underlain by Cussewago (Murrysville) 

Sandstone

Area in which Berea 

Sandstone overlaps 

Cussewago (Murrysville) Sandstone

Eastern limit of Berea 

Sandstone

Limit of Cussewago 

(Murrysville) Sandstone

25 50 MILES

FIGURE 4. Distribution of the Berea Sandstone and the Cussewago (Murrysville) Sandstone in northeastern Ohio and northwestern Pennsylvania.
G8 CONTRIBUTIONS TO STRATIGRAPHY

The Murrysville sand, which is an eastward-thickening and eastward-coarsening deltaic sandstone (fig. 1), has been traced in the 

subsurface from northeastern Ohio eastward across Pennsylvania to 

outcrops in the basal part of the Pocono Formation in the Conemaugh 

Gorge near Johnstown, Cambria County (Pepper and others, 1954, pi. 

14), and from western Pennsylvania eastward to outcrops of the 

Pocono Formation along the Horse Shoe Curve on the Allegheny 

Front west of Altoona, Blair County (Bayles, 1949, p. 1695). At the 

Horse Shoe Curve, the lower part of the Pocono Formation, the unnamed strata below the massive Burgoon Sandstone Member, is a 

550-foot sequence of light-gray, tan, white, and grayish-red quartzose 

sandstone and subgraywacke intercalated with gray, greenish-gray, 

and red sandy and silty shale and mudrock that contains an Early 

Mississippian Adiantites flora (Eead, 1955, p. 8). According to Swartz 

(1965, p. 24, 29, 30), the Murrysville sand of Bayles (1949) lies in the 

lower part of the sub-Burgoon strata and contains the Adiantites flora. 

Swartz showed that the Adiantites flora ranges from the Murrysville 

to within a few feet of the base of the Burgoon Sandstone Member 

where the Triphyllopteris flora supplants it. Eead and Mamay (1964^ 

p. 4) showed that the Adiantites flora is of Early Mississippian (Early 

Carboniferous) age and is present in the Kinderhook Series of the 

Midcontinent region and in the Lower Mississippian rocks of the 

Appalachian basin. These data clearly show that the Cussewago 

(Murrysville) Sandstone is of Kinderhook age.

Eead (1955, p. 8) reported an Early Mississippian Adiantites flora 

from shaly strata in the lower part of the Pocono Formation at several 

localities in the southern part of the Anthracite region of east-central 

Pennsylvania. As a part of a detailed mapping study, the sequence of 

red, greenish-gray, tan, brown, and black shale and intercalated 

white and gray coarse-grained sandstone which contained Read's 

Adiantites flora was named the Spechty Kopf Member by Trexler, 

Wood, and Arndt (1962). The Spechty Kopf was assigned to the 

Catskill Formation because it contained red shale. Trexler, Wood, and 

Arndt also subdivided the overlying Pocono Formation in the western 

part of the Southern Anthracite coal basin into the Beckville Member 

and the overlying Mount Carbon Member. The Spechty Kopf is the 

upper member of the Catskill Formation in this area and is lithologically transitional between the main body of the red beds of the Catskill 

below and the massive conglomeratic sandstones of the Pocono above. 

The presence of the Adiantites flora in the Spechty Kopf Member 

demonstrates a Mississippian age for most of the member, although 

because of the red shale in the Spechty Kopf it is considered a member 

of the predominantly Devonian Catskill Formation. Lithologically,
AGE OF BEDFORD SHALE, BEREA SANDSTONE, SUNBURY SHALE G9

the Spechty Kopf is similar to the rocks in the sub-Burgoon Pocono 

near Altoona. The presence of Adiantites in both sequences indicates 

that they are largely correlative. A flora has not yet been obtained from 

the Beckville Member of the Pocono in the Anthracite region, and 

although the relation of this unit to the strata along the Allegheny 

Front is not fully resolved, Swartz (1965, p. 22) correlated the Beckville with the shaly sub-Burgoon Pocono.

The depositional history and paleogeography of the Cussewago 

(Murrysville) Sandstone show that it is a part of the vast Pocono 

delta complex, whose source lay to the east of the Appalachian basin 

(Pelletier, 1958, p. 1056) and whose distal fringe covered parts of 

northeastern Ohio (Pepper and others, 1954, p. 59 and pi. 1). The sand 

body is oldest in central Pennsylvania nearest the source area where 

the Adiantites flora occurs throughout and is probably somewhat 

younger in northwestern Pennsylvania and northeastern Ohio where 

the Cussewago is overlapped by all but the oldest strata of the Bedford 

Shale. These data indicate that, except for the basal fossil zone, most 

of the Bedford Shale and the younger Berea Sandstone are younger 

than the Mississippian Cussewago (Murrysville) Sandstone. Because 

the Bedford and the Berea are underlain by the Cussewago (Murrysville) Sandstone and overlain by the Sunbury Shale, they too must 

be of Kinderhook age except possibly for the basal fossil zone of the 

Bedford.

Lithostratigraphic data indicate that the Berea Sandstone may be 

a temporal equivalent of the lower part of the Beckville Member of the 

Pocono Formation. In north-central Ohio, the Berea Sandstone is 

separated from the underlying Bedford Shale by a marked unconformity. At some places, stream channels were cut through the Bedford 

and into older strata and then were filled by Berea sand. Channel 

cutting in the Bedford in northern Ohio has been interpreted as a 

part of an episode of uplift and erosion which affected much of the 

Appalachian basin at the close of Bedford deposition (Pepper and 

others, 1954, p. 104). A part of the sheet of Cussewago (Murrysville) 

Sandstone (the area F sand of Pepper and others, 1954, p. 20, fig. 20) 

covers much of north-central West Virginia centering in Lewis 

County. This sand body was uplifted and partly truncated by subaerial 

erosion in an episode of crustal upwarp during which a large stream, 

the Gay-Fink Kiver, incised its channel into the sheet of sand. During 

the subsidence which followed, Berea sand backfilled the channel of 

the Gay-Fink River, and a transgressing epicontinental sea spread a 

blanket of fine-grained detritus over the sheet of Murrysville sand and 

the sand-filled Berea channel (Pepper and others, 1954, p. 77). Trexler, 

Wood, and Arndt (1961, p. B84) showed that in the Southern Anthra-
G10 CONTRIBUTIONS TO STRATIGRAPHY

cite coal basin, the Beckville Member of the Pocono Formation lies, 

unconfonnably on the underlying Spechty Kopf Member of the 

Catskill Formation which was gently folded during the interval of 

uplift preceding erosion. Only one episode of uplift and erosion appears to have occurred in the Appalachian basin during the Early 

Mississippian. If this is so, then the sandstones which were deposited 

upon the erosion surface produced during this episode must be near 

temporal equivalents. Presumably, therefore, the Berea Sandstone of 

northern Ohio and the Beckville Member of the Pocono of central 

Pennsylvania are near temporal equivalents.

AGE OF UNITS IN THE MICHIGAN BASIN

Because the ages assigned to the Bedford Shale, Berea Sandstone,, 

and Sunbury Shale in the Appalachian basin (Pepper and others, 

1954, p. 98) can be projected into the Michigan basin with confidence 

and in the absence of evidence to the contrary, much of the Bedford 

Shale, all the superjacent Berea Sandstone, and the Sunbury Shale 

of the Michigan basin are of Early Mississippian age and make up 

the Kinderhook Series there. Whether the basal part of the Bedford 

Shale in the Michigan basin is of Devonian or Mississippian age is a 

moot point at present.

SUMMARY

The data presented in this paper show that (1) Hymenozonotrttetes 

lepidophytus Kedo ranges across the Devonian-Mississippian boundary and cannot be used to differentiate Upper Devonian strata from 

Lower Mississippian strata in the Appalachian basin, (2) the basal 

few feet of the Bedford Shale in Ohio and Kentucky may be of very 

Late Devonian or very Early Mississippian age, and (3) most of the 

Bedford Shale and all the Berea Sandstone and Sunbury Shale are 

of Early Mississippian (Kinderhook) age.

REFERENCES CITED

Bayles, R. E., 1949, Subsurface Upper Devonian sections in southwestern Pennsylvania : Am. Assoc. Petroleum Geologists Bull., v. 33, no. 10, p. 1682-1703.

Collinson, Charles, James, G. W., Swann, D. H., Becker, L. E., Carlson, M. P., 

Dorheim, F. H., and Koenig, J. W., 1967, Devonian of the north-central region, United States, in Internat. Symposium on the Devonian System, Calgary, 1967 [Proc.]: Calgary, Alberta, Alberta Soc. Petroleum Geologists, 

v. 1, p. 933-971 [1968].

de Witt, Wallace, Jr., 1951, Stratigraphy of the Berea Sandstone and associated 

rocks in northeastern Ohio and northwestern Pennsylvania : Geol. Soc. America Bull., v. 62, p. 1347-1370.
AGE OF BEDFORD SHALE, BEREA SANDSTONE, SUNBURY SHALE Gil

Gutschick, R. C., and Moreman, W. L., 1967, Devonian-Mississippian boundary 

relations along the cratonic margin of the United States, in Internat. Symposium on the Devonian System, Calgary, Alberta, 1967 [Proc.]: Calgary, 

Alberta, Alberta Soc. Petroleum Geologists, v. 1, p. 1009-1023 [1968].

Hass, W. H., 1947, Conodont zones in Upper Devonian and Lower Mississippian. 

Formations of Ohio: Jour. Paleontology, v. 21, no. 2, p. 131-141.

 1956, Age and correlation of the Chattanooga Shale and the Maury 

Formation: U.S. Geol. Survey Prof. Paper 286, 47 p.

Mamet, Bernard, 1967, The Devonian-Carboniferous boundary in Eurasia, in Internat. Symposium on the Devonian System, Calgary, Alberta, 1967 [Proe.] : 

Calgary, Alberta, Alberta Soc. Petroleum Geologists, v. 1, p. 995-1007 [1968].

Oliver, W. A., Jr., de Witt, Wallace, Jr., Dennison, J. M., Hoskins, D. M., and: 

Huddle, J. W., 1967, Devonian of the Appalachian basin, United States, m 

Internat. Symposium on the Devonian System, Calgary, Alberta, 1967 

[Proc.]: Calgary, Alberta, Alberta Soc. Petroleum Geologists, v. 1, p. 1001- 

1040 [1968].

Pelletier, B. R., 1958, Pocono paleocurrents in Pennsylvania and Maryland: Geol. 

Soc. America Bull., v. 69, p. 1033-1064.

Pepper, J. F., de Witt, Wallace, Jr., and Demarest, D. F., 1954, Geology of the 

Bedford Shale and Berea Sandstone in the Appalachian basin: U.S. GeoL 

Survey Prof. Paper 259, 111 p.

Read, C. B., 1955, Floras of the Pocono Formation and the Price Sandstone in 

parts of Pennsylvania, Maryland, West Virginia, and Virginia: U.S. Geol. 

Survey Prof. Paper 263, 32 p.

Read, C. B., and Mamay, S. R., 1964, Upper Paleozoic floral zones and floral 

provinces of the United States: U.S. Geol. Survey Prof. Paper 454-K, 35 p.

Rhodes, F. H. T., Austin, R. L., and Druce, E. C., 1969, British Avonian (Carboniferous) conodont faunas and their value in local and intercontinental correlation : British Mus. (Nat. History) Geology Supp. 5, 313 p.

Sanford, B. V., 1967, Devonian of Ontario and Michigan, in Internat. Symposium 

on the Devonian System, Calgary, Alberta, 1967 [Proc.]: Calgary, Alberta, 

Alberta Soc. Petroleum Geologists, v. 1. p. 973-999 [1968].

Streel, Marcel, 1966, Criteres palynologiques pour une stratigraphie de"taillee du 

Tn la dans les bassins Ardenno-Rhe'nans: Soc. g&ol. Belgique Annales, v. 89, 

Bull. 3, p. B65-B92.

Swartz, F. M., 1965, Guide to the Horse Shoe Curve section between Altoona and 

Gallitzin, central Pennsylvania: Pennsylvania Geol. Survey Bull. (Gen. 

Geology Rept.) G50, 56 p.

Trexler, J. P., Wood, G. H., Jr., and Arndt, H. H., 1961, Angular unconformity 

separates Catskill and Pocono Formations in western part of the Anthracite 

region, Pennsylvania: U.S. Geol. Survey Prof. Paper 424-B, p. B84-B88.

 1962, Uppermost Devonian and Lower Mississippian rocks of the western

part of the Anthracite region of eastern Pennsylvania: U.S. Geol. Survey

Prof. Paper 450-C, p. C36-C39. 

Winslow, M. R., 1962, Plant spores and other microfossils from Upper Devonian

and Lower Mississippian rocks of Ohio: U.S. Geol. Survey Prof. Paper 364,

93 p.