MAYSVILLE WEST Roadcut
A very large exposure of Upper Ordovician rocks occurs ~2 miles northwest of the small city of Maysville, northeastern Kentucky. This is the Maysville West roadcut (although it is known by other names as well). Maysville West occurs just on the Kentucky side of the large Harsha Bridge over the Ohio River, along either side of the relatively new Rt. 62/68 bypass around Maysville (see map). The road cuts through Jersey Ridge, and was formerly known as Rt. 3071. This cut is excellent for seeing stratigraphy, but also has fantastic fossil collecting.
GPS of cut: 38° 40.407' North, 83° 47.830' West.
The Maysville West roadcut is the NE-SW trending whitish-gray streak just above the center of this satellite photo. The dark blue curving feature is the Ohio River. (Satellite photo provided by TerraMetrics & Google Earth)
Maysville West has nice exposures of the middle and upper Kope Formation (Edenian Stage, lower Cincinnatian Series), the Fairview Formation, and the Bellevue Limestone (both lower to middle Maysvillian Stage, middle Cincinnatian Series). The Bellevue Formation is also referred to as a member of the lower McMillan Formation/Grant Lake Formation.
The Kope occurs at the bottom of the cut and is generally shale-rich. The Fairview occupies the middle portions of the cut, and is roughly 50-50 limestone & shale. The Bellevue occupies the top portions of the cut, and is dominated by limestone beds.
The photos above & below show the northwestern side of the Maysville West roadcut. The top wall in the pics (above the top visible bench) is Bellevue. In general, the next three walls down are Fairview Formation. The wall seen at the bottom right corner of the pics is the top of the Kope Formation. The formation contacts do not coincide with bench levels, however.
The thick, light-colored limestone bed in the upper Fairview Formation here is a seismite horizon. It has highly convoluted bedding and contains limestone breccia. It has been interpreted as a portion of the ancient Ordovician seafloor that was significantly disturbed by a paleoearthquake. Seismites have been identified throughout Kentucky in the Middle and Upper Ordovician.
The Maysville West roadcut has produced some fantastic fossils, including rare edrioasteroids, “pockets” of glyptocrinid crinoid heads, cyclocystoids (including at least one unnamed & undescribed species), large Rusophycus carleyi burrows (made by Isotelus maximus asaphid trilobites), etc., etc. Maysville West is a great place for obtaining “star bryozoan” specimens (Constellaria florida) and large Platystrophia ponderosa orthid brachiopods. Horizons of large trepostome bryozoan masses (called “reefs” by at least one bryozoan worker) occur in the Bellevue Limestone near the top of the cut.