Early Silurian Formations of Southeastern Pennsylvania

Abstract

Research Article| September 30, 1931 Early Silurian Formations of Southeastern Pennsylvania CHARLES K. SWARTZ; CHARLES K. SWARTZ Search for other works by this author on: GSW Google Scholar FRANK M. SWARTZ FRANK M. SWARTZ Search for other works by this author on: GSW Google Scholar Author and Article Information CHARLES K. SWARTZ FRANK M. SWARTZ Publisher: Geological Society of America Received: 27 Oct 1930 First Online: 02 Mar 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 © 1931 Geological Society of America GSA Bulletin (1931) 42 (3): 621–662. https://doi.org/10.1130/GSAB-42-621 Article history Received: 27 Oct 1930 First Online: 02 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation CHARLES K. SWARTZ, FRANK M. SWARTZ; Early Silurian Formations of Southeastern Pennsylvania. GSA Bulletin 1931;; 42 (3): 621–662. doi: https://doi.org/10.1130/GSAB-42-621 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGSA Bulletin Search Advanced Search Abstract IntroductionHISTORICAL REVIEWThe problem presented by the nearly barren early Silurian formations of southeastern New York is of long standing. The basal deposits were named the Shawangunk by Mather in 1840.3 They were long considered to be Medinan in age because of their lithology and their position beneath supposed Niagaran limestone.Hartnagel subsequently showed that the limestone is not Niagaran but late Silurian Cobleskill,4 and concluded that the Shawangunk is Salinan. He seems to have based his opinion upon (1) the conditions of overlap in a transgressing sea, (2) the existence of a marked unconformity at its base, indicating the lapse of a long time for folding and erosion since the Ordovician,5 and the nonfossiliferous character of the strata, suggesting the aridity of the Salina.6 J. M. Clarke accepted Ilartnagel's correlation, fortifying his opinion by the discovery of numerous Eurypterids in the black shale in the Shawangunk which he . . . This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.