Geomorphology and paleontology of Riverbluff Cave, Springfield, Missouri
Riverbluff Cave developed near the southern margin of the Springfield Plateau as a single passage between James River and its tributary, Ward Branch. Portions of the cave preserve a general fining-upward sediment sequence, but with highly fossiliferous gravel beds near the middle. These gravel beds include fragments of various vertebrates, including mammoth and horse. Trackways and claw marks are also preserved atop the sediment in numerous locations. Cosmogenic isotope data provide burial dates for some of the sediment layers and fossil remains. The earliest sediment (reverse magnetic polarity) entered the cave at ∼1.1 Ma, while the fossiliferous gravel bed is dated at ∼0.74 Ma. The overlying laminated silts and clays have normal polarity with a burial date of ∼0.65 Ma at the base. Thus, the sediment sequence spans the Matuyama/Brunhes paleomagnetic datum, and records at least 450 ka of sedimentation within the cave. © 2010 The Geological Society of America. All rights reserved.
Geography, Geology, and Planning
Rovey II, Charles W., Matt Forir, Greg Balco, and David Gaunt. "Geomorphology and paleontology of Riverbluff Cave, Springﬁeld, Missouri." From Precambrian Rift Volcanoes to the Mississippian Shelf Margin: Geological Field Excursions in the Ozark Mountains 17 (2010): 31.
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