Nd isotopic composition of fossil fish teeth and debris from ODP Legs 138, 165, and 202


Autoria(s): Newkirk, Derrick R; Martin, Ellen E
Cobertura

MEDIAN LATITUDE: 8.745375 * MEDIAN LONGITUDE: -84.734465 * SOUTH-BOUND LATITUDE: -3.094930 * WEST-BOUND LONGITUDE: -90.817960 * NORTH-BOUND LATITUDE: 19.489600 * EAST-BOUND LONGITUDE: -78.739300 * DATE/TIME START: 1991-05-21T17:00:00 * DATE/TIME END: 2002-05-22T19:20:00

Data(s)

06/07/2009

Resumo

Changes in circulation associated with the shoaling of the Isthmus of Panama and the Caribbean carbonate crash in the Miocene were investigated using Nd isotopes from fossil fish teeth and debris from two sites in the Caribbean Basin (Ocean Drilling Program Sites 998 and 999) and two sites in the eastern equatorial Pacific (Sites 846 and 1241). The total range for e-Nd values measured from 18 to 4.5 Ma in the Caribbean is -7.3 to 0. These values are higher than Atlantic water masses (~-11) and range up to values equivalent to contemporaneous Pacific water masses, confirming that flow into the Caribbean Basin was composed of a mixture of Pacific and Atlantic waters, with an upper limit of almost pure Pacific-sourced waters. Throughout the Caribbean record, particularly during the carbonate crash (10-12 Ma), low carbonate mass accumulation rates (MARs) correlate with more radiogenic e-Nd values, indicating increased flow of corrosive Pacific intermediate water into the Caribbean Basin during intervals of dissolution. This flow pattern agrees with results from general ocean circulation models designed to study the effect of the shoaling of the Central American Seaway. Low carbonate MARs and high e-Nd values also correlate with intervals of increased Northern Component Water production and, therefore, enhanced conveyor circulation, suggesting that the conveyor may respond to changes in circulation associated with shoaling of the Central American Seaway. Reduced Pacific throughflow related to shoaling of the seaway led to a gradual increase in carbonate preservation and more Atlantic-like e-Nd values following the carbonate crash.

Formato

application/zip, 4 datasets

Identificador

https://doi.pangaea.de/10.1594/PANGAEA.723894

doi:10.1594/PANGAEA.723894

Idioma(s)

en

Publicador

PANGAEA

Relação

Circulation through the Central American Seaway during the Miocene Carbonate Crash (Data repository) (URI: ftp://rock.geosociety.org/pub/reposit/2009/2009019.pdf)

Direitos

CC-BY: Creative Commons Attribution 3.0 Unported

Access constraints: unrestricted

Fonte

Supplement to: Newkirk, Derrick R; Martin, Ellen E (2009): Circulation through the Central American Seaway during the Miocene carbonate crash. Geology, 37(1), 87-90, doi:10.1130/G25193A.1

Palavras-Chave #138-846B; 143Nd/144Nd; 165-998A; 165-999A; 202-1241A; Age; AGE; Calculated; Caribbean Sea; Colombia Basin, Caribbean Sea; Depth; DEPTH, sediment/rock; DRILL; Drilling/drill rig; e-Nd(0); e-Nd(T); epsilon-Neodymium (0); epsilon-Neodymium (T); Joides Resolution; Label; Leg138; Leg165; Leg202; Multi-collector inductively coupled plasma - mass spectrometer (MC-ICP-MS); Neodymium 143/Neodymium 144; North Pacific Ocean; Ocean Drilling Program; ODP; ODP sample designation; Sample code/label; South Pacific Ocean
Tipo

Dataset