Skip to Main Content
Skip Nav Destination

Significance of Silurian stromatolite-sphinctozoan reefs

Constance M. Soja
Significance of Silurian stromatolite-sphinctozoan reefs
Geology (Boulder) (April 1994) 22 (4): 355-358


Upper Silurian (Ludlovian) limestones from the Heceta Formation of southeastern Alaska (Alexander terrane) contain skeletal stromatolite reefs and stromatolite mud mounds that were colonized by sphinctozoan sponges. Internal growth cavities, synsedimentary marine cements, and stromatolite debris flows in slope deposits indicate that these reefs grew with relief at the seaward margin of the carbonate platform. The biotas under study have evolutionary significance because they contain the earliest widespread reef-building sphinctozoans and represent a previously unrecognized stage in the evolution of Phanerozoic microbial-metazoan (predominantly poriferan) reefs. On the basis of the presence of Silurian stromatolite-sphinctozoan deposits in southeastern Alaska, southwestern and west-central Alaska, and the Urals, this study also establishes a Late Silurian paleobiogeographic connection between the Alexander terrane, cratonic northwestern North America, and the Uralian region.

ISSN: 0091-7613
EISSN: 1943-2682
Serial Title: Geology (Boulder)
Serial Volume: 22
Serial Issue: 4
Title: Significance of Silurian stromatolite-sphinctozoan reefs
Author(s): Soja, Constance M.
Affiliation: Colgate University, Department of Geology, Hamilton, NY, United States
Pages: 355-358
Published: 199404
Text Language: English
Publisher: Geological Society of America (GSA), Boulder, CO, United States
References: 30
Accession Number: 1994-025828
Categories: Stratigraphy
Document Type: Serial
Bibliographic Level: Analytic
Illustration Description: illus. incl. sketch map
N51°00'00" - N72°00'00", W130°00'00" - E173°00'00"
N47°30'00" - N77°30'00", E56°00'00" - E70°00'00"
Country of Publication: United States
Secondary Affiliation: GeoRef, Copyright 2017, American Geosciences Institute. Reference includes data supplied by the Geological Society of America, Boulder, CO, United States
Update Code: 199412
Close Modal

or Create an Account

Close Modal
Close Modal