The late Miocene Panama isthmian strait

Abstract

Research Article| August 01, 1996 The late Miocene Panama isthmian strait Laurel S. Collins; Laurel S. Collins 1Museum of Paleontology, University of Michigan, Ann Arbor, Michigan 48109 Search for other works by this author on: GSW Google Scholar Anthony G. Coates; Anthony G. Coates 2Smithsonian Tropical Research Institute, Unit 0948, APO AA 34002-0948 Search for other works by this author on: GSW Google Scholar William A. Berggren; William A. Berggren 3Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543 Search for other works by this author on: GSW Google Scholar Marie-Pierre Aubry; Marie-Pierre Aubry 4Institut des Sciences de l'Evolution, Université Montpellier II, 37095 Montpellier Cedex 5, France Search for other works by this author on: GSW Google Scholar Jijun Zhang Jijun Zhang 5Department of Earth Sciences, Dalhousie University, Halifax, Nova Scotia, Canada Search for other works by this author on: GSW Google Scholar Geology (1996) 24 (8): 687–690. https://doi.org/10.1130/0091-7613(1996)024<0687:TLMPIS>2.3.CO;2 Article history first online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Laurel S. Collins, Anthony G. Coates, William A. Berggren, Marie-Pierre Aubry, Jijun Zhang; The late Miocene Panama isthmian strait. Geology 1996;; 24 (8): 687–690. doi: https://doi.org/10.1130/0091-7613(1996)024<0687:TLMPIS>2.3.CO;2 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 SocietyGeology Search Advanced Search Abstract Miocene sediments of the Caribbean Gatun and Chagres formations, Panama Canal basin, were deposited within an archipelagic strait that connected Caribbean and Pacific waters. Shallow-water (∼ 25 m) benthic foraminifera of the Gatun Formation have a strong Caribbean affinity, indicating that a significant interoceanic, biogeographic barrier had formed at ∼ 8 Ma. However, benthic foraminifera of the overlying Chagres Formation are bathyal and markedly Pacific in affinity, indicating that at ∼ 6 Ma, waters of the Panama isthmian strait deepened to ∼ 200–500 m and Pacific bathyal waters flowed into the Caribbean. The Chagres Formation crops out at the Caribbean entrance to the Panama Canal in a large wedge of cross-laminated sandstone and coquina. The cross-laminations and coarse grain size indicate high-energy currents atypical of bathyal settings. We infer that a jet of the Pacific North Equatorial Countercurrent–Equatorial Undercurrent passed through the Panama isthmian strait to deposit these sediments on the Caribbean side. This later entry of Pacific taxa into the Caribbean had no apparent effect on the subsequent composition of Caribbean faunas. 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.