The provenance of Cretaceous to Quaternary sediments in the Tarfaya basin, SW Morocco: Evidence from trace element geochemistry and radiogenic Nd–Sr isotopes

Ali, Sajid, Stattegger, Karl, Garbe-Schönberg, Dieter, Frank, Martin, Kraft, Steffanie and Kuhnt, Wolfgang (2014) The provenance of Cretaceous to Quaternary sediments in the Tarfaya basin, SW Morocco: Evidence from trace element geochemistry and radiogenic Nd–Sr isotopes Journal of African Earth Sciences, 90 . pp. 64-76. DOI 10.1016/j.jafrearsci.2013.11.010.

[img] Text
Ali.pdf - Published Version
Restricted to Registered users only

Download (4Mb) | Contact

Supplementary data:

Abstract

We present trace element compositions, rare earth elements (REEs) and radiogenic Nd–Sr isotope analyses of Cretaceous to recent sediments of the Tarfaya basin, SW Morocco, in order to identify tectonic setting, source rocks composition and sediments provenance. The results suggest that the sediments originate from heterogeneous source areas of the Reguibat Shield and the Mauritanides (West African Craton), as well as the western Anti-Atlas, which probably form the basement in this area. For interpreting the analyzed trace element results, we assume that elemental ratios such as La/Sc, Th/Sc, Cr/Th, Th/Co, La/Co and Eu/Eu∗ in the detrital silicate fraction of the sedimentary rocks behaved as a closed system during transport and cementation, which is justified by the consistency of all obtained results. The La/Y-Sc/Cr binary and La–Th–Sc ternary relationships suggest that the Tarfaya basin sediments were deposited in a passive margin setting. The trace element ratios of La/Sc, Th/Sc, Cr/Th and Th/Co indicate a felsic source. Moreover, chondrite-normalized REE patterns with light rare earth elements (LREE) enrichment, a flat heavy rare earth elements (HREE) and negative Eu anomalies can also be attributed to a felsic source for the Tarfaya basin sediments. The Nd isotope model ages (TDM = 2.0–2.2 Ga) of the Early Cretaceous sediments suggest that sediments were derived from the Eburnean terrain (Reguibat Shield). On the other hand, Late Cretaceous to Miocene–-Pliocene sediments show younger model ages (TDM = 1.8 Ga, on average) indicating an origin from both the Reguibat Shield and the western Anti-Atlas. In contrast, the southernmost studied Sebkha Aridal section (Oligocene to Miocene–Pliocene) yields older provenance ages (TDM = 2.5–2.6 Ga) indicating that these sediments were dominantly derived from the Archean terrain of the Reguibat Shield.

Document Type: Article
Additional Information: WOS:000331155100006
Keywords: Trace elements; Nd–Sr isotopes; Provenance; Tarfaya basin
Research affiliation: Kiel University
OceanRep > GEOMAR > FB1 Ocean Circulation and Climate Dynamics > FB1-P-OZ Paleo-Oceanography
Refereed: Yes
DOI etc.: 10.1016/j.jafrearsci.2013.11.010
ISSN: 1464-343X
Projects: Transdrift
Date Deposited: 24 Mar 2014 11:55
Last Modified: 31 May 2017 11:42
URI: http://eprints.uni-kiel.de/id/eprint/23938

Actions (login required)

View Item View Item

Document Downloads

More statistics for this item...