•  
  •  
 

Document Type

Research

Keywords

Mississippian, Gilmore City Limestone, Recent Bahamian beach deposits, fossiliferous lenses, lithofacies

Abstract

Thousands of small fossils were collected from unusual lenses within the Cyathophyllum Zone, Gilmore City Limestone (Mississippian) in a large quarry near Humboldt, Iowa. These rare lenses occur in an interval 1-2.5m thick that shows an extreme variability of facies. An intensive search of other Gilmore City outcrops revealed no similar lenses. The rest of the interval, outside the lenses, contained larger fossils and fossil fragments. The small fossils in the lenses are remarkably well preserved, the gastropods particularly so. Comparison of the Gilmore City Limestone with Recent oolitic deposits at Paradise Island in the Bahamas leads to the conclusion that these unusual lenses probably were a backshore deposit. The Bahamian deposits provide evidence for interpretation of these fossils as size-sorted rather than dwarfed. Early carbonate coating is hypothesized to explain the exceptional preservation of the Mississippian fossils.

Publication Date

June 1982

Journal Title

Proceedings of the Iowa Academy of Science

Volume

89

Issue

2

First Page

68

Last Page

70

Copyright

© Copyright 1982 by the Iowa Academy of Science, Inc.

Language

EN

File Format

application/pdf

Share

COinS
 

To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.