Latitude:                         40° 33' 45"N

Longitude:                      80° 05' 07"W

Quadrangle:                    Emsworth 7 1/2'

Age:                                Pennsylvanian

Formation(s):                  Casselman Formation, Morgantown sandstone and Birmingham sandstone with the Wellersburg coal in between.  

Purpose:                         This site provides a view of two large channel sandstones sitting on atop the other.

Park in berm of I-279, as far from the traffic lane as possible. Not recommended for children. Very dangerous highway.

The above map does not show the present road system.

No direct Pat transit service.

Driving Directions:

From the Cathedral of Learning, Drive 0.7 mi. west on Fifth Avenue. Make a Left on Craft Av. Go 0.1 mi., then make a right onto Blvd. of Allies, go 1.6 mi. then bear right onto I-579. Stay on I-579 across the Allegheny River then get onto I-279 North. Go approximately 9.2 miles. Outcrop is on your right.

See map and figures.

The lower portion of the outcrop consists of thick-bedded, massive, gray sandstone. The upper part of the outcrop consists of a massive yellowish sandstone. Around the bend form where the outcrop first begins, a thin coal seam with underlying dark-colored shale is found between the two large sandstone units. To the north, the two sandstone units appear as one becuse the Morgantown channel scoured into the top of the Birmingham sandstone (summarized from Hutchinson, 1995).

Geologic History: Environment of Deposition:

Here, the Morgantown sandstone is a distributary channel that has cut into and through a large section of pre-existing sediments to rest on the Wellersburg coal and underlying Birmingham sandstone.  The setting is lower delta plain.

Lower Delta Plain Environment (from Horne and others, 1978).

Typical Sections from the lower delta plain, bottom section with crevass splay (from Horne and others, 1978).

Typical Sequence from lower delta plain (from Horne and others, 1978).

Click on the thumbnails below for pictures of the outcrops:

A view of the west side of the outcrop showing the shale sequence and the Connellsville (?) sandstone at the top.

No fossils found here except for fragmented plant remains in the dark shales and coal.

Berryhill, H. L., Jr., Schweinfurth, S. P., and Kent, B. H., 1971, Coal-bearing Upper Pennsylvanian and Lower Permian Rocks, Washington area, Pennsylvania: U. S. Geological Survey Professional Paper 621, 47p.

Edmunds, W. E., Skema, V. W., Flint, N. K., 1999, Pennsylvanian, in Shultz, C. H., ed, The Geology of Pennsylvania, Pennsylvania Geological Survey Special Publication 1, p. 149-169.

Harper, J. A., 1990, Fossil Collecting in the Pittsburgh Area, Pittsburgh Geological Society Guidebook. 50 pages.

Horne, J. C., Ferm, J. C., Caruccio, F. T., and Baganz, B. P., 1978, Depositional models in coal exploration and mine planning in Appalachian region: American Association of Petroleum Geologists Bulletin, v. 62, p. 2379-2411.

Hutchinson, P. J., ed., 1995, Pittsburgh Geological Society Golden Anniversary (1945-1995) Field Guide Book. Pittsburgh Geological Society.

Johnson, M. E., 1928, Geology and Mineral Resources of the Pittsburgh Quadrangle, Pennsylvania: Pennsylvania Geological Survey Bulletin A 27, 236 p.

Leighton, H. 1945, The Geology of Pittsburgh and its Environs: A Popular Account of the General Geological Features of the Region: Carnegie Institute Press, 2nd edition, Pittsburgh, PA , 80p.

Shaw, E. W., and Munn, M. J., 1911, Geologic Atlas of the United States: Burgettstown-Carnegie Folio, United States Geological Survey Folio 177 Field Edition, 123p.

Wagner, W. R., and others, 1970, Geology of the Pittsburgh Area: Pennsylvania Geological Survey General Geology Report G 59, 145p.

Click here for  an image of the County Geologic Map (1880)