Our Rich History: Ice Age glaciers shaped the site of Newport; climate change will always have impact


Part 35 of our series, Resilience and Renaissance: Newport, Kentucky, 1795-2020.

By Stanley Hedeen
Special to NKyTribune

Newport is bounded on the west by the Licking River and on the north by the Ohio River. Both streams often flood, but a gravel and sand terrace holds Downtown Newport above all but the highest inundations. These geographic features are the result of Ice Age visits by the Pre-Illinoian, Illinoian and Wisconsinan continental glaciers, with the latter two ice sheets being named for the states in which geologists found the first evidence of their past existence.

The glaciers advanced into the Newport region during intervals of global cooling. In each interval, an enormous amount of snow built up on northern North America, the result of more snow falling in winter than melting in summer. The accumulating weight pressed the snow into glacial ice, which slowly spread outward at the margin of the ice sheet. The southern limit of a continental glacier was where the ice at its front melted away at the same rate as the glacial ice pushed forward. A glacier retreated and finally disappeared as warmer global temperatures returned.

Preglacial landscape approximately 2,000,000 years ago. N = Newport. From Stanley  Hedeen, Natural History of the Cincinnati Region (Cincinnati: Cincinnati Museum Center, 2006)

Prior to the start of the Ice Age, and before the Ohio River existed, the Licking River ran north through a channel located in Campbell County east of Newport. The Licking continued in Ohio by running through eastern Cincinnati and past Hamilton to its mouth on the Teays River, which flowed across central Ohio, Indiana and Illinois to drain into the Mississippi River in the vicinity of St. Louis.

The Pre-Illinoian Glacier rearranged the landscape about a million years ago. Advancing from the north, the ice sheet obliterated the Teays River and relocated the Licking River westward to form the channel that now serves as Newport’s western border.

The glacier also blocked the channels of north-flowing streams located between the Mississippi River and the Appalachian Mountains to the east. The glacial ice acted as a dam, causing lakes to form in the stream valleys. As one lake formed it overflowed into the next, which then overflowed into the next, and so on until a new drainage system to the Mississippi River was formed along the margin of the ice sheet. This drainage was the early Ohio River.

The path of the early Ohio River through the Kentucky-Ohio-Indiana region did not pass Newport, but instead looped from Cincinnati’s Lunken Airport past St. Bernard to Lawrenceburg. The Licking River flowed into the early Ohio River at St. Bernard.

Pre-Illinoian glacial instant approximately 1,000,000 years ago. N = Newport. From Stanley  Hedeen, Natural History of the Cincinnati Region (Cincinnati: Cincinnati Museum Center, 2006)

About a quarter million years ago, the region was visited by a second continental ice sheet, the Illinoian Glacier. The advancing ice blocked the Ohio River’s northern loop in the region, forcing the stream to cut its present path from Lunken Airport past Newport to Lawrenceburg. This channel of the Ohio River now serves as Newport’s northern boundary and receives the water of the Licking River at the city’s General James Taylor Park.

The region’s last glacier, the Wisconsinan, pushed into the area approximately 70,000 years ago. The ice sheet advanced into the northern portion of Cincinnati before it began its retreat about 19,500 years ago. Like the earlier glaciers, the Wisconsinan scraped rock fragments from the land across which the glacial ice moved as it progressed south from the arctic. Meltwater from the glacier carried immense amounts of the rock sediment into the Ohio River basin, forming a level fill across its bottom.

In the thousands of years since the retreat of the Wisconsinan Glacier, the Ohio and Licking Rivers have carved their channels into the level fill. This downcutting has left terraces of glacial outwash material, mostly gravel and sand, along each side of the Ohio River. Downtown Newport’s location on a terrace elevates it above most floods, so only the highest inundations require closure of the city’s levee gates.

Illinoian glacial instant approximately 250,000 years ago. N = Newport. From Stanley  Hedeen, Natural History of the Cincinnati Region (Cincinnati: Cincinnati Museum Center, 2006)

Since the founding of Newport, mammal bones and teeth have been unearthed from the Wisconsinan glacial outwash beneath the city. The Ice Age fossils reveal the types of mammals that lived in the area about 20,000 years ago when a sparse forest of spruces and firs covered the land. Plant-eaters included mammoths, mastodons, ground sloths, musk-oxen and peccaries, which in turn were eaten by dire wolves, saber-toothed cats and other carnivores.

Humans arrived in the Kentucky-Ohio-Indiana region sometime before 12,000 years ago. These first Native Americans on the site of Newport were the descendants of people who had colonized the New World, possibly by crossing the Bering Land Bridge from Siberia to Alaska or by boating along the intercontinental coastlines to reach North America. Newport’s first humans gathered plants and hunted Ice Age mammals, likely causing the extinction of several animal species.

When the region’s average annual temperature increased at the end of the Ice Age about 10,000 years ago, the area’s dominant vegetation changed from evergreen conifers to the deciduous trees that still comprise Newport’s woodlands. Forest mammals now include deer, raccoons, opossums, skunks and foxes. Due to the global warming that is now occurring, many of the region’s current plants and animals will be replaced by migrants from the South, for example, magnolia trees and armadillos. Climate change will again alter the biological community of Newport, just as it did at the close of the Ice Age.

Stanley Hedeen is an Emeritus Professor of Biology at Xavier University, where he also served as Dean of Arts and Sciences. He has authored books on Big Bone Lick, Mill Creek and the natural history of the Cincinnati region.

We want to learn more about the history of your business, church, school, or organization in our region (Cincinnati, Northern Kentucky, and along the Ohio River). If you would like to share your rich history with others, please contact the editor of “Our Rich History,” Paul A. Tenkotte, at tenkottep@nku.edu. Paul A. Tenkotte, PhD is Professor of History at Northern Kentucky University (NKU) and the author of many books and articles.


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