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LAWRENCE -- The fossilized tracks and burrows of prehistoric animals, or trace fossils, found in rocks in Coffey County are described in a new book from the Kansas Geological Survey, based at the University of Kansas. These fossils reveal much about the ancient environment when a rock layer was deposited.
"Ichnology of Pennsylvanian Equatorial Tidal Flat -- The Stull Shale Member at Waverly, Eastern Kansas" focuses on trace fossils found near Waverly, in east-central Kansas. The layer of rock that contained the fossils, the Stull Shale Member of the Kanwaka Shale, was deposited during the Pennsylvanian Period of geologic history, about 300 million years ago.
Paleontologists Gabriela Mangano and Luis Buatois of the Instituto Superior de Correlacion Geologica in Argentina, Ron West of Kansas State University and Chris Maples of Indiana University and formerly of the Survey collaborated on the book, which identifies many of the trace fossils and discusses the environment and time the fossils were formed. The researchers identified traces of 41 organisms in the rocks, including bivalves, brittle stars and sea anemones.
By analyzing the traces and studying the rocks, the researchers identified the environment at the time the rocks were deposited as a tidal flat near the equator. Conditions varied from a sand flat to a mud flat to a river channel. At times this environment was extremely good at preserving ripple marks, burrows, tracks and tubes.
"These rocks represent evidence of an ecosystem with extreme changes in temperature, salinity and energy of the water," said the authors. "The high quality of the preservation of these traces allows an excellent opportunity to study conditions under which the rocks were deposited and to understand the importance of these tidal flats in evolutionary terms."
Copies of the book are available from the Kansas Geological Survey, 1930 Constant Ave., Lawrence, KS 66047; (785) 864-3965. Each costs $30, plus $5 for shipping and handling. Kansas residents should add 7.3 percent sales tax.
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