TY - JOUR

T1 - Record of Albian to early Cenomanian environmental perturbation in the eastern sub-equatorial Pacific

AU - Navarro-Ramirez, J. P.

AU - Bodin, S.

AU - Heimhofer, U.

AU - Immenhauser, A.

N1 - Funding information: This project was supported by the Deutsche Forschungsgemeinschaft (DFG, project no. BO-365/2-1 ) and by the Deutscher Akademischer Austauschdienst (DAAD) through a scholarship to J.P.N. ( PKZ: A/11/97387 ). We thank the Geological Survey of Peru (INGEMMET) for important logistical support. W. Gomez is thanked for his help during field expedition. Analytical work was performed in the isotope laboratories at Bochum and Hannover by A. Niedermayr, D. Buhl and C. Wenske. The present manuscript benefitted from the comments of two anonymous Palaeo3 reviewers and editorial guidance by F. Surlyk.

PY - 2015/4/1

Y1 - 2015/4/1

N2 - The present paper documents and discusses a new Albian-early Cenomanian carbon isotope (δ13Ccarb and δ13Corg) curve from the subequatorial Eastern Pacific in Peru. Chemostratigraphic evidences for the expression of the OAE1b set and for OAE1c and OAE1d are presented. This dataset is relevant inasmuch as previous work is strongly biased towards study sites in North America (Western Interior Basin), in Europe (Tethys) and the Pacific realm. A comparison of the carbon isotope stratigraphy obtained in Peru with published sections from the Central and Western Pacific, the Western Atlantic and Northern and Western Tethys reveals an overall good agreement supporting the global nature of the isotope patterns described here. The δ13C from Peru record is constrained by biostratigraphic evidence and 87Sr/86Sr isotope stratigraphy using well-preserved oyster shells. Furthermore, we document the development of a heterozoan epeiric-neritic mixed carbonate-siliciclastic ramp in the Western Platform of Peru and its corresponding sedimentary facies associations. This dataset was used to elucidate the complex interplay of climatic changes, nutrient supply, and platform drowning, leading to the following conclusions: (i) an upper Aptian-lower Albian major change from siliciclastic-dominated to carbonate sedimentation coincided with the impact of the Kilian Level, (ii) a lower Albian incipient platform drowning linked to the impact of the Paquier Level, (iii) A lower middle Albian major demise of neritic carbonate production that coincides with the Leenhardt Level, followed by middle Albian condensed sedimentation that reports prominent negative values in δ13Ccarb prior to the onset of OAE1c and (iv) finally, renewed carbonate ramp production during the upper Albian-lower Cenomanian. The data shown here represent the foundation for future work documenting the mid-Cretaceous of Peru and its implications for the palaeoceanography of the SE subequatorial Pacific.

AB - The present paper documents and discusses a new Albian-early Cenomanian carbon isotope (δ13Ccarb and δ13Corg) curve from the subequatorial Eastern Pacific in Peru. Chemostratigraphic evidences for the expression of the OAE1b set and for OAE1c and OAE1d are presented. This dataset is relevant inasmuch as previous work is strongly biased towards study sites in North America (Western Interior Basin), in Europe (Tethys) and the Pacific realm. A comparison of the carbon isotope stratigraphy obtained in Peru with published sections from the Central and Western Pacific, the Western Atlantic and Northern and Western Tethys reveals an overall good agreement supporting the global nature of the isotope patterns described here. The δ13C from Peru record is constrained by biostratigraphic evidence and 87Sr/86Sr isotope stratigraphy using well-preserved oyster shells. Furthermore, we document the development of a heterozoan epeiric-neritic mixed carbonate-siliciclastic ramp in the Western Platform of Peru and its corresponding sedimentary facies associations. This dataset was used to elucidate the complex interplay of climatic changes, nutrient supply, and platform drowning, leading to the following conclusions: (i) an upper Aptian-lower Albian major change from siliciclastic-dominated to carbonate sedimentation coincided with the impact of the Kilian Level, (ii) a lower Albian incipient platform drowning linked to the impact of the Paquier Level, (iii) A lower middle Albian major demise of neritic carbonate production that coincides with the Leenhardt Level, followed by middle Albian condensed sedimentation that reports prominent negative values in δ13Ccarb prior to the onset of OAE1c and (iv) finally, renewed carbonate ramp production during the upper Albian-lower Cenomanian. The data shown here represent the foundation for future work documenting the mid-Cretaceous of Peru and its implications for the palaeoceanography of the SE subequatorial Pacific.

KW - Carbonates

KW - Chemostratigraphy

KW - Mid-Cretaceous

KW - OAE

KW - Pacific

UR - http://www.scopus.com/inward/record.url?scp=84923040327&partnerID=8YFLogxK

U2 - 10.1016/j.palaeo.2015.01.025

DO - 10.1016/j.palaeo.2015.01.025

M3 - Article

AN - SCOPUS:84923040327

VL - 423

SP - 122

EP - 137

JO - Palaeogeography, Palaeoclimatology, Palaeoecology

JF - Palaeogeography, Palaeoclimatology, Palaeoecology

SN - 0031-0182

ER -