ABSTRACT Pleistocene glacial and interglacial episodes had a profound influence on erosion, sediment transport, and topographic expression in the Midwestern United States. Northern Kentucky hosts a variety of fluvial and glacial features that record these Quaternary advances and retreats of the Laurentide ice sheet. This field trip highlights the major glacial and interglacial episodes of the Pleistocene, including the Pliocene–Early Pleistocene Teays drainage system, the Early–Middle Pleistocene pre–Illinois glacial Episode, the Middle Pleistocene Yarmouth interglacial, the Illinois glacial Episode in the Middle Pleistocene, the Sangamon interglacial, and the Late Pleistocene Wisconsin Episode. The Old Kentucky River was tributary to the Teays, depositing sands at ca. 1.5 Ma, confirmed by multiple 10 Be- 26 Al cosmogenic radionuclide burial ages. Glacial till uncoformably overlies Old Kentucky River sands and demonstrates that pre-Illinois ice extended into Kentucky. The modern-day course of the Ohio River was incised after the pre−Illinois Episode, and then aggraded with transportation of Illinois Episode glacial outwash. Deposition of outwash at the mouths of tributaries caused impoundment and slackwater deposition in tributary valleys; the Claryville Clay has long been assumed to represent a pre-Illinois lacustrine deposit, but new optically stimulated luminescence feldspar geochronology yields a Middle Pleistocene age of ca. 320 ka. We have not observed Illinoian till in Kentucky. The final advance of the Laurentide ice sheet did not reach Kentucky, however, high sediment volumes were transported along the Ohio River and impounded tributaries, similar to the Illinois Episode.

Abstract Applying time-series analyses using Fourier transform and multi-taper methods to low-field, mass-specific magnetic susceptibility (χ) measurements on marine samples from well-studied shale and limestone outcrops of the Upper Ordovician (Edenian Stage; Upper Katian) Kope Formation, northern Kentucky, corroborates direct visual identification in outcrops of Milankovitch eccentricity ( c. 405 and 100 ka), obliquity and precessional climate cycles. Because individual outcrops were too short and deposition too chaotic to yield significant time-series results, it was necessary to build a c. 50 m thick composite sequence from three well-correlated outcrops to quantify the cyclicity. Time-series analysis was then performed using χ measured for 1004 closely spaced samples covering the section. Milankovitch bands are recorded in the time-series data from the composite. We tested this result by comparison of these bands to cyclic packages in outcrop, which correspond to thicknesses represented in the time-series datasets. This is particularly well defined for the eccentricity and obliquity cycles, with precessional bands being evident but as less well-defined packages of beds.