Consequences of shoaling of the Central American Seaway determined from modeling Nd isotopes. (7th March 2014)

• Record Type: Journal Article
• Authors: Sepulchre, P.; Arsouze, T.; Donnadieu, Y.; Dutay, J.‐C.; Jaramillo, C.; Le Bras, J.; Martin, E.; Montes, C.; Waite, A. J.
• Is Part Of: Paleoceanography. Volume 29:Number 3(2014:Sep.)
• Page Start: 176
• Page End: 189
• Publication Date: 2014-03-07
• Subjects: Paleoceanography -- Periodicals; 551.46
• DOI: 10.1002/2013PA002501
• Languages: English
• ISSNs: 0883-8305

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p>The Central American Seaway played a pivotal role in shaping global climate throughout the late Cenozoic. Recent geological surveys have provided new constraints on timing of the seaway shoaling, while neodymium isotopic (<italic>ε</italic>_Nd) data measured on fossil teeth, debris, and ferromanganese crusts have helped define the history of water masses in the region. Here we provide the first 3‐D simulations of <italic>ε</italic>_Nd responses to the shoaling seaway. Our model suggests that a narrow and shallow seaway is sufficient to affect interoceanic circulation, that inflow/outflow balance between the Caribbean and the Antilles responds nonlinearly to sill depth, and that a seaway narrower than 400 km is consistent with an active Atlantic meridional overturning circulation during the late Miocene. Simulated <italic>ε</italic>_Nd values in the Caribbean confirm that inputs from radiogenic Pacific waters in the Caribbean decrease as the seaway shoals. Despite model limitations, a comparison between our results and <italic>ε</italic>_Nd values recorded in the Caribbean helps constrain the depth of the Central American Seaway through time, and we infer that a depth between 50 and 200 m could have been reached 10 Ma ago.</p> </abstract>