TY - JOUR
T1 - Biostratigraphy, mineralogy and geochemistry of the Trabakua Pass and Ermua sections in Spain
T2 - Paleocene-Eocene transition
AU - Bolle, Marie Pierre
AU - Adatte, Thierry
AU - Keller, Gerta
AU - Von Salis, Katharina
AU - Hunziker, Johannes
PY - 1998
Y1 - 1998
N2 - Isotopic, geochemical and bulk mineralogical analyses in the Trabakua and Ermua sections, Basque Basin, reveal major changes across the Paleocene-Eocene transition. Expanded sedimentary records exhibit a gradual decrease of 1.0‰ in δ 13C values in the lower part of Zone P5 followed by a more rapid 3‰ negative excursion. The 3‰ δ 13C excursion is associated with an abrupt decrease in carbonate sedimentation, increased detrital flux and decreased grain size which suggest changes in marine/atmospheric currents and/or size and structure of the ocean carbon reservoir. The clays recognized at Trabakua record a deep burial diagenesis as indicated by two generations of chlorite, the presence of mixed-layers chlorite-smectite and illite-smectite, the absence of smectite and the near absence of kaolinite. The very low δ 18O values (<-3.5‰) throughout the Trabakua and Ermua sections reflect diagenetic alteration rather than paleotemperatures. Because of deep burial diagenesis and very poorly preserved microfossils, the Trabakua Pass and Ermua sections are not optimal potential stratotypes for the Paleocene-Eocene boundary.
AB - Isotopic, geochemical and bulk mineralogical analyses in the Trabakua and Ermua sections, Basque Basin, reveal major changes across the Paleocene-Eocene transition. Expanded sedimentary records exhibit a gradual decrease of 1.0‰ in δ 13C values in the lower part of Zone P5 followed by a more rapid 3‰ negative excursion. The 3‰ δ 13C excursion is associated with an abrupt decrease in carbonate sedimentation, increased detrital flux and decreased grain size which suggest changes in marine/atmospheric currents and/or size and structure of the ocean carbon reservoir. The clays recognized at Trabakua record a deep burial diagenesis as indicated by two generations of chlorite, the presence of mixed-layers chlorite-smectite and illite-smectite, the absence of smectite and the near absence of kaolinite. The very low δ 18O values (<-3.5‰) throughout the Trabakua and Ermua sections reflect diagenetic alteration rather than paleotemperatures. Because of deep burial diagenesis and very poorly preserved microfossils, the Trabakua Pass and Ermua sections are not optimal potential stratotypes for the Paleocene-Eocene boundary.
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M3 - Article
AN - SCOPUS:0031666174
VL - 91
SP - 1
EP - 25
JO - Ecologae Geologicae Helvetiae
JF - Ecologae Geologicae Helvetiae
SN - 0012-9402
IS - 1
ER -