A primitive variety of Palaeoaplysina laminaeformis Krotov is the primary biotic constituent of a two-meter-thick biostrome in the upper Ely Limestone of western Utah. Associated fusulinaceans and stromatoporoids indicate an early Desmoinesian (Middle Pennsylvanian) age, making it the oldest documented occurrence of non-ancestral Palaeoaplysina in the world. Plate-supported packstone with 40-60% interstitial peloidal mud and silt-size fossil debris constitutes the dominant biostrome rock fabric. During the Late Carboniferous, non-ancestral palaeoaplysinids were restricted to the Ely and Sublett basins of Utah and Idaho, respectively. By Early Permian time, however, they played a significant role in the construction of reefs and biostromes across the entire northern margin of Laurussia.

This content is PDF only. Please click on the PDF icon to access.

First Page Preview

First page PDF preview
You do not currently have access to this article.