Influence of the Central American Seaway and Drake Passage on ocean circulation and neodymium isotopes: A model study

Abstract The Oligocene-Miocene Transition (OMT) was a time of significant oceanic, climatic, and biotic change, but there is still a great deal we do not understand about its effects, particularly in terms of ocean circulation. The Central American Seaway (CAS) was an important ocean gateway at this time; recent fully coupled modeling results have suggested a possible temporary reversal of surface flow, from westward to eastward, during the OMT. Such a flow reversal would have altered numerous oceanographic properties and the dispersal of marine taxa. Here, we find a mismatch in the timing of the Atlantic vs. Pacific first appearances of the tropical mixed layer planktic foraminifer Paragloborotalia kugleri, a key zonal marker for the OMT. The first appearance ages for P. kugleri from fourteen ocean drilling sites vary from ∼23.2–23.05 Ma in the Pacific to ∼23.05–22.7 Ma in the Atlantic. Key requirements for including a site in this compilation are: 1) sampling resolution; 2) independent non-biostratigraphic chronology, such as magnetostratigraphy or orbital tuning; and 3) a preference for shore-based biostratigraphic analyses rather than shipboard estimates. Although we explore alternative explanations, we conclude that, given the restricted nature of the CAS gateway, timing of dispersal, and results from previous modeling efforts, CAS flow reversal is the most parsimonious explanation for the delayed first appearance of P. kugleri in the Atlantic relative to the Pacific. We suggest that after originating in the tropical Pacific, P. kugleri was initially blocked from dispersal into the Atlantic by westward surface circulation through the CAS during the latest Oligocene. During the OMT, circulation reversed and Pacific surface water flowed through the CAS into the Atlantic, allowing P. kugleri to disperse into the Atlantic. Previously published ocean-climate simulations suggest that the cause of this reversed flow may be related to the progressive constriction of Tethys and opening of the Drake Passage at the time of the OMT, compounded by a short-lived glaciation event in Antarctica and possible change in meridional temperature gradient and prevailing wind patterns in the tropics.

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Drake Passage and Central American Seaway controls on the distribution of the oceanic carbon reservoir

Global and Planetary Change ◽

10.1016/j.gloplacha.2015.02.011 ◽

2015 ◽

Vol 128 ◽

pp. 72-82 ◽

Cited By ~ 7

Author(s):

Jeremy G. Fyke ◽

Marc D'Orgeville ◽

Andrew J. Weaver

Keyword(s):

Drake Passage ◽

Central American ◽

Central American Seaway ◽

Carbon Reservoir ◽

Oceanic Carbon

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Tropical seaways played a more important role than high latitude seaways in Cenozoic cooling

Climate of the Past ◽

10.5194/cp-7-801-2011 ◽

2011 ◽

Vol 7 (3) ◽

pp. 801-813 ◽

Cited By ~ 33

Author(s):

Z. Zhang ◽

K. H. Nisancioglu ◽

F. Flatøy ◽

M. Bentsen ◽

I. Bethke ◽

...

Keyword(s):

Ocean Circulation ◽

Deep Water ◽

Drake Passage ◽

Central American ◽

The Arctic ◽

Early Eocene ◽

High Latitudes ◽

The West ◽

Early Eocene Climatic Optimum ◽

Tectonic Events

Abstract. Following the Early Eocene climatic optimum (EECO, ~55–50 Ma), climate deteriorated and gradually changed the earth from a greenhouse into an icehouse, with major cooling events at the Eocene-Oligocene boundary (∼34 Ma) and the Middle Miocene (∼15 Ma). It is believed that the opening of the Drake Passage had a marked impact on the cooling at the Eocene-Oligocene boundary. Based on an Early Eocene simulation, we study the sensitivity of climate and ocean circulation to tectonic events such as the closing of the West Siberian Seaway, the deepening of the Arctic-Atlantic Seaway, the opening of the Drake Passage, and the constriction of the Tethys and Central American seaways. The opening of the Drake Passage, together with the closing of the West Siberian Seaway and the deepening of the Arctic-Atlantic Seaway, weakened the Southern Ocean Deep Water (SODW) dominated ocean circulation and led to a weak cooling at high latitudes, thus contributing to the observed Early Cenozoic cooling. However, the later constriction of the Tethys and Central American Seaways is shown to give a strong cooling at southern high latitudes. This cooling was related to the transition of ocean circulation from a SODW-dominated mode to the modern-like ocean circulation dominated by North Atlantic Deep Water (NADW).

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Tropical seaways played a more important role than high latitude seaways in Cenozoic cooling

Climate of the Past Discussions ◽

10.5194/cpd-7-965-2011 ◽

2011 ◽

Vol 7 (2) ◽

pp. 965-996 ◽

Cited By ~ 2

Author(s):

Z. Zhang ◽

K. H. Nisancioglu ◽

F. Flatøy ◽

M. Bentsen ◽

I. Bethke ◽

...

Keyword(s):

Ocean Circulation ◽

Deep Water ◽

Drake Passage ◽

Central American ◽

The Arctic ◽

Early Eocene ◽

High Latitudes ◽

The West ◽

Early Eocene Climatic Optimum ◽

Tectonic Events

Abstract. Following the Early Eocene climatic optimum (EECO, ~55–50 Ma), climate deteriorated and gradually changed the earth from a greenhouse into an icehouse, with major cooling events at the Eocene-Oligocene boundary (~34 Ma) and the Middle Miocene (~15 Ma). It is believed that the opening of the Drake Passage had a marked impact on the cooling at the Eocene-Oligocene boundary. Based on an Early Eocene simulation, we study the sensitivity of climate and ocean circulation to the tectonic events such as the closing of the West Siberian Seaway, the deepening of the Arctic-Atlantic Seaway, the opening of the Drake Passage, and the constriction of the Tethys and Central American seaways. The opening of the Drake Passage, together with the closing of the West Siberian Seaway, and the deepening of the Arctic-Atlantic Seaway, weakens the Southern Ocean Deep Water (SODW) dominated ocean circulation and leads to a weak cooling at high latitudes, thus contributing to the observed Early Cenozoic cooling. However, the later constriction of the Tethys and Central American Seaways is shown to give a strong cooling at southern high latitudes. This cooling is related to the transition of ocean circulation from a SODW-dominated mode to the modern-like ocean circulation dominated by North Atlantic Deep Water (NADW).

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Colder Subarctic Pacific with larger sea ice caused by closure of the Central American Seaway and its influence on the East Asian monsoon: a climate model study

Geological Society London Special Publications ◽

10.1144/sp342.15 ◽

2010 ◽

Vol 342 (1) ◽

pp. 265-277 ◽

Cited By ~ 5

Author(s):

Tatsuo Motoi ◽

Wing-Le Chan

Keyword(s):

Sea Ice ◽

Asian Monsoon ◽

Climate Model ◽

East Asian Monsoon ◽

East Asian ◽

Central American ◽

Subarctic Pacific ◽

Model Study ◽

Central American Seaway

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FLOW REVERSAL IN THE CENTRAL AMERICAN SEAWAY DURING OR AFTER THE OLIGOCENE MIOCENE TRANSITION

10.1130/abs/2017am-297585 ◽

2017 ◽

Author(s):

Andrew Jeffrey Fraass ◽

◽

R. Mark Leckie ◽

Christopher M. Lowery ◽

Robert DeConto

Keyword(s):

Flow Reversal ◽

Central American ◽

Central American Seaway

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Comparing the impacts of Miocene–Pliocene changes in inter-ocean gateways on climate: Central American Seaway, Bering Strait, and Indonesia

Earth and Planetary Science Letters ◽

10.1016/j.epsl.2016.03.010 ◽

2016 ◽

Vol 444 ◽

pp. 116-130 ◽

Cited By ~ 33

Author(s):

Chris M. Brierley ◽

Alexey V. Fedorov

Keyword(s):

Central American ◽

Bering Strait ◽

Central American Seaway

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Graphic correlation of deep sea and shallow marine deposits from the Central American Isthmus region: implications for Late Neogene paleoclimatology

The Paleontological Society Special Publications ◽

10.1017/s2475262200006481 ◽

1992 ◽

Vol 6 ◽

pp. 88-88

Author(s):

Harry J. Dowsett

Keyword(s):

Costa Rica ◽

High Resolution ◽

Ocean Circulation ◽

Deep Sea ◽

Sea Surface ◽

Central American ◽

Major Barrier ◽

Late Neogene ◽

The Caribbean ◽

Central American Isthmus

The stratigraphic record in Panama and Costa Rica preserves the biologic and climatic changes associated with the formation of a major barrier to marine migration and ocean circulation. Creating a high resolution temporal framework within which stratigraphic sections found on the Isthmus can be interpreted is fundamental to our understanding the history and importance of these units.The Isthmus contains rich marine macro- and microfaunas and floras on both the Pacific and Atlantic margins. Planktic foraminifers and calcareous nannofossils are common and often well preserved. Preliminary analysis of these fossils reveals a rich sedimentary record spanning the Late Miocene to Pleistocene. Multivariate statistical analyses of these assemblages provide environmental estimates. Unfortunately, traditional methods of biostratigraphy are limited in their ability to create a high resolution temporal framework for the region. For example, a majority of deposits analyzed can be placed in planktic foraminiferal zone N19 (early Pliocene). In order to answer paleobiologic and paleoclimatic questions one requires more precise correlations between sections and some indication of duration of sedimentation represented by various sections.In an attempt to overcome the shortcomings of traditional biostratigraphic methods, the Graphic Correlation method has been applied to selected sequences on the Central American Isthmus. Graphic correlation (GC) is a procedure by which two sequences can be compared and correlated using a wide variety of stratigraphic information simultaneously. A GC model of late Neogene planktic foraminifer, calcareous nannofossil, and paleomagnetic reversal events has been produced through compositing of more than 26 deep sea cores and ocean margin sequences. Following routine GC procedures the positions of all fossil first and last occurrences from a number of sections on the Caribbean and Pacific sides of the Central American Isthmus (Panama and Costa Rica) have been recorded. These sections have been correlated to the GC model and hence, to each other, providing a temporal framework for the Isthmus units.Selected sections were then correlated to other sequences such as near-by deep sea cores which have been analyzed for sea surface temperature and salinity to gain a better understanding of the overall paleoceanographic development of the region between 5 and 2 Ma. For example, correlation of units on the Caribbean side of the Isthmus with DSDP Site 502 indicates little to no change in sea surface temperatures during the entire time the Isthmus was reaching closure. Mid-to-high latitude sites exhibit amplification of warming with increasing latitude. The shoaling Isthmus, while having negligible effects on tropical marine temperatures, was responsible for increased meridional heat transport which resulted in a North Atlantic warming about 3 Ma. A general model for paleoceanographic changes during the time of closure will be discussed.

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