Disruption of community structure at isthmus closure

Author(s): Jain, Sreepat; Buzas, Martin A.; Hayek, Lee-Ann C.
Author Affiliation(s): Primary:
Smithsonian Institution, National Museum of Natural History, Department of Paleobiology, Washington, DC, United States
Volume Title: Geological Society of America, 2008 annual meeting
Source: Abstracts with Programs - Geological Society of America, 40(6), p.562-563; Geological Society of America, 2008 annual meeting, Houston, TX, Oct. 5-9, 2008. Publisher: Geological Society of America (GSA), Boulder, CO, United States. ISSN: 0016-7592 CODEN: GAAPBC
Note: In English
Summary: Two deep-sea sites, ODP 999a and DSDP 502a, 320 Km apart within the Colombian basin, western Caribbean from depths of 2828 m and 3051 m respectively, were examined to assess the effects on the benthic foraminiferal community of the rise of the Isthmus of Panama and the subsequent closure of the Central American Seaway (CAS). Each site was subjected to SHE analysis, an information-theoretic method of biofacies identification and analysis of community structure. Preliminary results indicate that at bathyal-abyssal depths in the Caribbean, changes in the overall benthic foraminiferal species diversity were minor. In contrast, changes in benthic foraminiferal community structure are easily recognized at around 4.2 Ma, the approximate time of the CAS closure. Additionally, the community structure within the Colombian Basin changed at both Sites 999a and 502a before the CAS closure, but the events were asynchronous. After the closure no further oceanographic events disrupted community structures. Thus, this study demonstrates that oceanographic events are easily recognizable through changes in community structure even when changes in traditional proxies are minor.
Year of Publication: 2008
Research Program: DSDP Deep Sea Drilling Project
IPOD International Phase of Ocean Drilling
ODP Ocean Drilling Program
Key Words: 12 Stratigraphy, Historical Geology and Paleoecology; Atlantic Ocean; Benthic taxa; Biofacies; Caribbean Sea; Cenozoic; Central America; Central American Seaway; Colombian Basin; Communities; DSDP Site 502; Deep Sea Drilling Project; Deep-sea environment; Foraminifera; IPOD; Invertebrata; Leg 165; Leg 68; Marine environment; Microfossils; North Atlantic; ODP Site 999; Ocean Drilling Program; Panama; Protista; Species diversity; Tertiary
Coordinates: N124437 N124437 W0784422 W0784422
N112925 N112925 W0792247 W0792247
Record ID: 2012056902
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data supplied by the Geological Society of America, Boulder, CO, United States