Erian Series

Devonian System

Type locality, reference sections, and former use of name: Named by Kindle (1899, p.8) for Jeffersonville, Clark County, Ind., where the formation is well exposed during low-water stages at the Falls of the Ohio, the Jeffersonville Limestone was originally described as the limestone between the "Sellersburg beds [North Vernon Limestone] and the Catenipora beds of the Niagara." At the type locality and in most of Clark County, Ind., this unit as originally understood does rest on rocks of Niagaran age, but northward along the outcrop of what was long called a separate formation, the Geneva Dolomite (Middle Devonian) underlies Jeffersonville rocks. The descriptive term Corniferous Limestone was used by Borden in 1874 for Jeffersonville rocks, but "Corniferous" has also been used in Indiana to refer to the entire Muscatatuck Group (Middle Devonian). The term Corniferous in both senses has been abandoned.

Three reference sections were designated by Burger and Patton (1970, p.77) in three quarries: (1) Meshberger Stone Co. quarry, Bartholomew County (SE¼SE¼NE¼ sec. 6, T. 8 N., R. 7 E.), (2) Berry Materials quarry at North Vernon, Jennings County (SW¼SW¼SE¼ sec. 27, T. 7 N., R. 8 E.), and is) T. J. Atkins and Co. quarry near Claysburg, Clark County (W2 Clark Military Grant 10).

Expansion of definition and related nomenclature: From the time of earliest naming of the Jeffersonville Limestone and the Geneva Dolomite, stratigraphers have disagreed on their age relations. Subsurface and other studies of the 1960's and 1970's, however, have favored the idea of intimate relationships between typical Jeffersonville and Geneva rocks and between typical Jeffersonville and subsurface rocks in Illinois that had been called the Dutch Creek Sandstone. Therefore, the Dutch Creek was assigned member status in the basal Jeffersonville (Becker, 1974, p. 38), and the Geneva was assigned the same status in a similar but not identical basal Jeffersonville position (Droste and Shaver, 1975a, p. 403-404). The latter authors (p. 404-406) also named the Vernon Fork Member for nontypical Jeffersonville beds that had been known by a variety of descriptive names, including "laminated beds." (See details in the Dutch Creek, Geneva, and Vernon Fork articles.)

With these nomenclatural and definitive changes, the Jeffersonville is considered here to consist in generally ascending order of the Dutch Creek Sandstone, Geneva Dolomite, and Vernon Fork Members; also, it consists of rocks unnamed to member, so that in any one place one or more parts of this four-part circumstance may apply.

The Geneva assignment affects the Jeffersonville reference sections only in the first two quarries noted above, as the Geneva is developed in its typical lithology in those two quarries but not in the third quarry. (See, for example, the section in the Berry quarry that was described by Droste and Shaver, 1975a, p. 405.)

Description: Many geologists and lay persons have provided accounts of the Jeffersonville at the Falls of the Ohio (that is, at the type locality) especially because of the prolific corals and the remarkable fossil community that they and other fossils represent. The rocks here have generally been described in terms of three to six biozones (for example, Burger and Patton, 1970, p. 77, three zones; Powell, 1970, four zones; and Oliver, 1976, p. 19, six zones). In Perkins's (1963) terms the type Jeffersonville consists in ascending order of (1) mostly brown coarse-grained medium- to thick-bedded, highly fossiliferous limestone and dolomite limestone (Coral Zone =? Lower and Upper Coral Zones of Oliver, 1968), (2) variably colored coarse-grained medium-bedded stromatoporoidal limestone (Amphipora Zone), (3) variably colored dense to medium-grained cherty hard fossiliferous limestone (Brevispirifer gregarious Zone), and (4 and 5) light-colored thin-bedded to massive granular cherty fossiliferous limestone (Bryozoan-Brachiopod Zone below and Paraspirifer acuminates Zone above).

Although Perkins (1963), Droste and Shaver (1975a), and Oliver (1976) were able to trace or correlate some of the biozones several tens of miles along the outcrop area northward from the Falls of the Ohio, the rocks of these zones also grade northward into finer grained rocks that are termed pellsparites and mud-supported pelmicrites and biomicrites (Droste and Shaver, 1975a, p. 402). These lithologies refer to the descriptive terms laminated beds, chalk beds, and fine-grained dolomite beds of common use in the literature. In much of western central Indiana these rocks include rounded frosted quartz sand grains within the dolomite matrices (Becker, 1974, p. 35, fig. 17). Where present, the Geneva exhibits brown and tan fine- to medium-grained, somewhat massive, finely vuggy dolomite that has different relationships with the Falls-area biozones at different places of observation. (See the Geneva article.)

All these circumstances permit conceptualization of the Jeffersonville in two principal facies, a southern, or classic, facies and a west-central Indiana facies (Droste and Shaver, 1975a, p. 401). In the southern, classic facies, however, the biozones developed at the Falls are hardly recognizable in the subsurface, and in 12 southwestern Indiana counties this facies is modified by the Dutch Creek Sandstone Member (Becker, 1974, fig. 19).

The Geneva and Vernon Fork lithologies dominate the west-central facies, but even here tongues of the classic facies are present in some places, for example, the Paraspirifer acuminates Zone. Also, a bed of silicified corals and stromatoporoids is found in eastern and northern Jennings County. This bed was called "burrstone" by Owen (1839, p. 16), "Buhrstone bed" by Kindle (1901, p. 558), and "silicified bed" by Dawson (1941, p. 19-20). (See also Patton and Dawson, 1955.)

The Jeffersonville overlies the New Harmony Group (Lower Devonian) both conformably and unconformably in the far southwestern Indiana counties, and elsewhere in its Indiana distribution it unconformably overlies Lower to Upper Silurian rocks ranging stratigraphically from the Salamonie Dolomite (Laurel Member) upward to the upper part of the Wabash Formation. This is an erosionally truncating relationship, the amount of truncation increasing eastward from the Illinois Basin and southeastward along the area of outcrop. The Jeffersonville is overlain by the North Vernon Limestone, possibly everywhere unconformably.

By definition in relation to Detroit River rocks in Indiana, the Jeffersonville is restricted to the southwestern and western flanks of the Kankakee and Cincinnati Arches and to the Illinois Basin. It ranges in thickness from an erosional edge in all up dip locales to more than 200 feet (61 in) in far southwestern Indiana. The greater thickness, therefore, refers to the southern facies, and the thickest part of the west-central facies is about 140 feet (43 in) thick (Droste and Shaver, 1975a, figs. 6 and 7).

Correlation: The Jeffersonville has traditionally been correlated with the Onondaga Formation (Erian) of New York on the basis of its macrofossils. During more recent time, correlation has been facilitated by many studies of Middle Devonian Conodonts in North America and Europe and by wide-spread recognition of the Tioga Bentonite Bed. A lower, non-Geneva part of the Jeffersonville was assigned to the Icriodus iatericrescens robustus Zone before Dutch Creek and Geneva rocks were added to the Jeffersonville, whereas upper Jeffersonville rocks were assigned to the Icriodus augustus Zone. This zone extends stratigraphically upward to include lower North Vernon rocks. (See Orr, 1971, p. 16-17, for these conodont-zonal assignments.) These determinations show that the Jeffersonville is largely Eifelian (global standard) in age, and a lower part is probably as old as late Emsian, a possibility that is also suggested from the work of Conkin and Conkin (1979b, p. 14), Wright (1980, p. 5-7), and Sparling (1983, fig. 9). (See also Rickard, 1975, pl. 3; Oliver, 1976; Klapper and Ziegler, 1979; and Shaver and others, 1985.)

Close to approximate correlatives of the Indiana Jeffersonville include the Grand Tower Limestone, southern Illinois; the Detroit River Formation, northern Indiana and western Ohio; the Lucas Formation and possibly the upper parts of the Amherstburg Formation and the Sylvania Sandstone, southern Michigan; the Columbus Limestone and the lower part of the Dundee Limestone, central to northwestern; Ohio the Onondaga Formation, New York; and the Jeffersonville Limestone, western Kentucky.