Saved in:
Bibliographic Details
Main Authors: Lofi, Johanna, Voelker, Antje H L, Ducassou, Emmanuelle, Hernandéz-Molina, Francisco Javier, Sierro, Francisco Javier, Bahr, André, Galvani, Aurélie, Lourens, Lucas Joost, Pardo-Igúzquiza, Eulogio, Pezard, Philippe Adrien, Rodríguez-Tovar, Francisco Javier, Williams, Trevor J
Format: Dataset Open Access
Language:en
Published: PANGAEA 2017
Subjects:
Online Access:https://doi.org/10.1594/PANGAEA.870926
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867167675052982272
author Lofi, Johanna
Voelker, Antje H L
Ducassou, Emmanuelle
Hernandéz-Molina, Francisco Javier
Sierro, Francisco Javier
Bahr, André
Galvani, Aurélie
Lourens, Lucas Joost
Pardo-Igúzquiza, Eulogio
Pezard, Philippe Adrien
Rodríguez-Tovar, Francisco Javier
Williams, Trevor J
author_facet Lofi, Johanna
Voelker, Antje H L
Ducassou, Emmanuelle
Hernandéz-Molina, Francisco Javier
Sierro, Francisco Javier
Bahr, André
Galvani, Aurélie
Lourens, Lucas Joost
Pardo-Igúzquiza, Eulogio
Pezard, Philippe Adrien
Rodríguez-Tovar, Francisco Javier
Williams, Trevor J
collection Datos científicos de ciencias marinas y ambientales
contents The Contourite Depositional Systems (CDS) in the Gulf of Cádiz and on the West Iberian margin preserve a unique archive of Mediterranean Outflow Water (MOW) variability over the past 5.3 Ma. These CDS have been recently drilled in several places during the IODP Expedition 339. These drill sites now offer a new window to the internal Pliocene and Quaternary architecture of the CDS. In this study, we use downhole and core Gamma Ray (GR) data acquired from 5 sites drilled in the CDS along the middle slope and 1 site drilled in the deeper setting of the lower slope, out of the MOW path. The GR data primarily tracks the clay content in the sediment and is the expression of sediment supply and, for sites drilled in the CDS, of the bottom current processes. Both appear astronomically controlled as shown by spectral analysis performed on the GR data. Results also reveal that the GR log patterns correlate well across the sites over the last 1.4 My. Several GR horizons corresponding to drops in GR values were identified, most of which fit with coarse-grained deposits observed in cores and interpreted as contourite beds. The GR horizons are interpreted as isochronous horizons, providing a regional scale chronostratigraphic framework for the CDS depositional records with an accuracy of ~ 20 ky. We further assess the spatial and temporal variability of the CDS hiatuses at the regional scale.
format Dataset Open Access
id pangaea_https___doi_org_10_1594_PANGAEA_870926
institution PANGAEA
language en
publishDate 2017
publisher PANGAEA
record_format pangaea
spellingShingle Portuguese contourite depositional systems derived from Natural Gamma Ray records analysed during IODP Exp339
Lofi, Johanna
Voelker, Antje H L
Ducassou, Emmanuelle
Hernandéz-Molina, Francisco Javier
Sierro, Francisco Javier
Bahr, André
Galvani, Aurélie
Lourens, Lucas Joost
Pardo-Igúzquiza, Eulogio
Pezard, Philippe Adrien
Rodríguez-Tovar, Francisco Javier
Williams, Trevor J
Integrated Ocean Drilling Program / International Ocean Discovery Program; IODP
The Contourite Depositional Systems (CDS) in the Gulf of Cádiz and on the West Iberian margin preserve a unique archive of Mediterranean Outflow Water (MOW) variability over the past 5.3 Ma. These CDS have been recently drilled in several places during the IODP Expedition 339. These drill sites now offer a new window to the internal Pliocene and Quaternary architecture of the CDS. In this study, we use downhole and core Gamma Ray (GR) data acquired from 5 sites drilled in the CDS along the middle slope and 1 site drilled in the deeper setting of the lower slope, out of the MOW path. The GR data primarily tracks the clay content in the sediment and is the expression of sediment supply and, for sites drilled in the CDS, of the bottom current processes. Both appear astronomically controlled as shown by spectral analysis performed on the GR data. Results also reveal that the GR log patterns correlate well across the sites over the last 1.4 My. Several GR horizons corresponding to drops in GR values were identified, most of which fit with coarse-grained deposits observed in cores and interpreted as contourite beds. The GR horizons are interpreted as isochronous horizons, providing a regional scale chronostratigraphic framework for the CDS depositional records with an accuracy of ~ 20 ky. We further assess the spatial and temporal variability of the CDS hiatuses at the regional scale.
title Portuguese contourite depositional systems derived from Natural Gamma Ray records analysed during IODP Exp339
topic Integrated Ocean Drilling Program / International Ocean Discovery Program; IODP
url https://doi.org/10.1594/PANGAEA.870926