Portal de Periódicos da CAPES

Early Neogene history of the Central American arc from Bocas del Toro, western Panama

2003; Geological Society of America; Volume: 115; Linguagem: Inglês

10.1130/0016-7606(2003)115 2.0.co;2

1943-2674

Anthony G. Coates, Marie‐Pierre Aubry, William A. Berggren, Laurel S. Collins, Michael J. Kunk,

earthquake and tectonic studies

Research Article| March 01, 2003 Early Neogene history of the Central American arc from Bocas del Toro, western Panama Anthony G. Coates; Anthony G. Coates 1Smithsonian Tropical Research Institute, P.O. Box 2072, Balboa, Republic of Panama Search for other works by this author on: GSW Google Scholar Marie-Pierre Aubry; Marie-Pierre Aubry 2Institut des Sciences de l'Evolution, Université de Montpellier, Montpellier, Cedex 5, France Search for other works by this author on: GSW Google Scholar William A. Berggren; William A. Berggren 3Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA Search for other works by this author on: GSW Google Scholar Laurel S. Collins; Laurel S. Collins 4Department of Earth Sciences, Florida International University, Miami, Florida 33199, USA Search for other works by this author on: GSW Google Scholar Michael Kunk Michael Kunk 5U.S. Geological Survey, M.S. 963, Denver Federal Center, Denver, Colorado 80225, USA Search for other works by this author on: GSW Google Scholar Author and Article Information Anthony G. Coates 1Smithsonian Tropical Research Institute, P.O. Box 2072, Balboa, Republic of Panama Marie-Pierre Aubry 2Institut des Sciences de l'Evolution, Université de Montpellier, Montpellier, Cedex 5, France William A. Berggren 3Department of Geology and Geophysics, Woods Hole Oceanographic Institution, Woods Hole, Massachusetts 02543, USA Laurel S. Collins 4Department of Earth Sciences, Florida International University, Miami, Florida 33199, USA Michael Kunk 5U.S. Geological Survey, M.S. 963, Denver Federal Center, Denver, Colorado 80225, USA Publisher: Geological Society of America Received: 27 Mar 2001 Revision Received: 13 Jun 2002 Accepted: 17 Jun 2002 First Online: 01 Jun 2017 Online ISSN: 1943-2674 Print ISSN: 0016-7606 Geological Society of America GSA Bulletin (2003) 115 (3): 271–287. https://doi.org/10.1130/0016-7606(2003)115 2.0.CO;2 Article history Received: 27 Mar 2001 Revision Received: 13 Jun 2002 Accepted: 17 Jun 2002 First Online: 01 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn Email Permissions Search Site Citation Anthony G. Coates, Marie-Pierre Aubry, William A. Berggren, Laurel S. Collins, Michael Kunk; Early Neogene history of the Central American arc from Bocas del Toro, western Panama. GSA Bulletin 2003;; 115 (3): 271–287. doi: https://doi.org/10.1130/0016-7606(2003)115 2.0.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 SocietyGSA Bulletin Search Advanced Search Abstract A newly discovered sequence of lower to middle Miocene rocks from the eastern Bocas del Toro archipelago, western Panama, reveals the timing and environment of the earliest stages in the rise of the Isthmus of Panama in this region. Two new formations, the Punta Alegre Formation (lower Miocene, Aquitanian to Burdigalian) and the Valiente Formation (middle Miocene, Langhian to Serravallian), are here named and formally described. The Punta Alegre Formation contains a diagnostic microfauna of benthic and planktic foraminifera and calcareous nannofossils that indicate deposition in a 2000-m-deep pre-isthmian neotropical ocean from as old as 21.5–18.3 Ma. Its lithology varies from silty mudstone to muddy foraminiferal ooze with rare thin microturbidite layers near the top. The Valiente Formation, which ranges in age from 16.4 to ca. 12.0 Ma, lies with slight angular unconformity on the Punta Alegre Formation and consists of five lithofacies: (1) columnar basalt and flow breccia, (2) pyroclastic deposits, (3) coarse-grained volcaniclastic deposits, (4) coral-reef limestone with diverse large coral colonies, and (5) marine debris-flow deposits and microturbidites. These lithofacies are interpreted to indicate that after ca. 16 Ma a volcanic arc developed in the region of Bocas del Toro and that by ca. 12 Ma an extensively emergent archipelago of volcanic islands had formed. 39Ar/40Ar dating of basalt flows associated with the fossiliferous sedimentary rocks in the upper part of the Valiente Formation strongly confirms the ages derived from planktic foraminifera and nannofossils. Paleobathymetric analysis of the two new formations in the Valiente Peninsula and Popa Island, in the Bocas del Toro archipelago, shows a general shallowing from lower- through upper-bathyal to upper-neritic and emergent laharic and fluviatile deposits from ca. 19 to 12 Ma. The overlying nonconformable Bocas del Toro Group contains a lower transgressive sequence ranging from basal nearshore sandstone to upper-bathyal mudstone (ca. 8.1–5.3 Ma) and an upper regressive sequence (5.3–3.5 Ma). A similar paleobathymetric pattern is observed from the Gatun to Chagres Formations (12–6 Ma) in the Panama Canal Basin area and in the Uscari, Rio Banana, Quebrada Chocolate, and Moin Formations (8–1.7 Ma) in the southern Limón Basin of Costa Rica. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.