News Release, Kansas Geological Survey, Dec. 30, 2011
LAWRENCE--A new full-color geologic map of Saline County showing broad river valleys dissecting hilly terrain is available from the Kansas Geological Survey based at the University of Kansas.
Surficial geologic maps highlight the type and age of rock layers found on the surface or immediately below the vegetation and soil. The map also has a three-dimensional quality that accentuates the area's topography.
"This map, the first detailed geologic map of Saline County, is an important addition to the Survey's decades-long geologic mapping effort," said Survey Interim Director Rex Buchanan.
Mapped by now-retired Survey geologist James McCauley, the county's varied surface geology ranges in age from Permian and Cretaceous to recently deposited stream sediment.
Permian and Cretaceous rock layers--formed from deposits in shallow seas that rose and receded across the area more than 275 million years ago and about 100 million years ago, respectively--are composed mainly of sandstone, siltstone, and shale.
The Smoky Hills, capped by Cretaceous-age Dakota and Kiowa sandstones and found mainly in the western part of the county, offer the most noticeable relief. The highest point in the county, approximately 1,660 feet above sea level, is three miles northwest of Brookville.
"The Dakota and Kiowa sandstones dominant in the bedrock of the Smoky Hills provide some of the best scenic vistas in the state," Buchanan said.
In much more recent times, the Smoky Hill, Saline, and Solomon rivers and their tributaries cut through the rugged landscape to create wide, relatively flat stream valleys filled with clay, silt, sand, and gravel deposits.
Almost all of Saline County's towns, including Salina, Brookville, Gypsum, Assaria, Smolan, and New Cambria, are located in these valleys. Old river channels, carved out and abandoned over thousands of years, and small wind-derived sand dunes south of Gypsum are shown on the map.
Once flowing southward to the Arkansas River, the Smoky Hill was diverted during the glacial age several hundred thousand years ago into a neighboring waterway through the process of stream capture, or stream piracy, and now runs northeast to the Kansas River.
Many of the county's natural resources have been extracted for commercial use. Nearly 22.8 million barrels of oil have been produced in Saline County since 1929. In 2010, 65,720 barrels of oil were produced from 101 wells.
Sand and gravel from alluvium deposits along the Smoky Hill, Saline, and Solomon rivers, is used mainly for construction aggregate. Open pits are marked on the map.
In the late nineteenth century, gypsum was mined east of Salina and near the town of Gypsum. Near the confluence of the Solomon and Smoky Hill rivers, the dissolution of underlying gypsum beds created a broad area of subsidence.
Although salt also occurs in the subsurface, in western Saline County, it has never been commercially mined here. For a short time, calcite-cemented Kiowa sandstone, locally called "quartzite," was quarried just east of Bavaria.
In addition to geologic and hydrologic characteristics, the map includes towns, roads (from Federal highways to unimproved roadways), elevation contours at 10-meter intervals, township and range boundaries, and the boundary of the Smoky Hills National Guard Range.
Drawn in full-color to differentiate rock layers, the computer-generated geologic map features shaded relief to give the map its three-dimensional look and emphasize the landscape's topography. The map is at a scale of 1:50,000 so that one inch on the map equals about 3/4 mile of actual distance.
Besides the map, the 59" x 40" sheet contains an illustrated rock column, which shows the order in which the rock units were deposited over time, and a description of each unit.
Copies of the Saline County map are available from the Kansas Geological Survey at 1930 Constant Ave., Lawrence, KS 66047-3724 (phone 785-864-3965, email firstname.lastname@example.org) and at 4150 W. Monroe St., Wichita, KS 67209-2640 (phone 316-943-2343, email email@example.com).
The cost is $15 plus shipping and handling. Inquire about shipping and handling charges and, for Kansas residents, sales tax. More information about the maps and other KGS products is available at the Survey's web site (http://www.kgs.ku.edu/).