Ozark Plateau—Introduction
Ozark Plateau--Intro |
Ozark Plateau--Rocks and Minerals
Ozark Plateau--Places to Visit | Other regions
Download fact sheet on the rocks and minerals of the Ozark Plateau.
The Ozark Plateau, as its name suggests, is part of the Ozarks of Missouri, Oklahoma, and Arkansas. Bounded by the Spring River on the west, this corner of southeastern Kansas covers about 55 square miles and includes the towns of Baxter Springs and Galena. This region contains the oldest surface rocks in the state, limestones that formed about 345 million years ago during the later part of the Mississippian Period.
These rocks show that during the Late Mississippian, the land was alternately above and below sea level. When the sea advanced, limestones (and occasionally shales) were deposited. When the sea retreated, erosion set in.
The Mississipian limestones contain chert (or flint). Because chert is much harder and more resistant to weathering than limestone, erosion of the softer limestone has left a thick blanket of chert gravel on the hilltops and ridges.
The thin and rocky soil of the region, combined with steep slopes, makes most of the region unsuitable for farming. Cropland is restricted to the valley floors of Shoal Creek and Spring River. Many of the hillsides are covered with hardwood forests, predominantly oaks and hickories, along with other trees, shrubs, and vines.
Water flows over Mississippian limestone in Cherokee County. |
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Like the rest of southeast Kansas, the Ozark Plateau averages more than 40 inches of precipitation a year, making it one of the wettest places in the state. Water also affects the landscape of the region. Percolating through the joints and fractures of the Mississipian limestones, water creates caves and feeds seeps and springs, which in turn drain into clear streams that flow over gravel beds in steep-walled valleys. These stream valleys produce the region's topographic relief. The region's highest point (with an elevation of 1,040 ft) is located just a few miles east of one of the lowest points along the Spring River (elevation 770 ft). |
Text by Liz Brosius, Kansas Geological Survey. Unless noted otherwise, illustrations by Jennifer Sims, Kansas Geological Survey; photographs by John Charlton, Kansas Geological Survey.
Ozark Plateau--Intro |
Ozark Plateau--Rocks and Minerals
Ozark Plateau--Places to Visit | Other regions
General geology, rocks and minerals, and places to visit in the state's physiographic regions (including PDF factsheets for downloading)
Information about common Kansas fossils
Photos and descriptions of sites of geologic (and other) interest in Kansas
Descriptions of various rocks and minerals found in Kansas, including mineral ID tables and hardness scale
Overviews of various geology topics, ranging from Earth's age to the state's mining history
Online guidebooks, descriptions, and photos from KGS public field trips in Kansas