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Université de Neuchâtel

Phosphorus and the roles of productivity and nutrient recycling during oceanic anoxic event 2

Mort, Haydon P. ; Adatte, Thierry ; Föllmi, Karl B. ; Keller, Gerta ; Steinmann, Philipp ; Matera, Virginie ; Berner, Zsolt ; Stüben, Doris

In: Geology, 2007, vol. 35, no. 6, p. 483-486

Four sections documenting the impact of the late Cenomanian oceanic anoxic event (OAE 2) were studied in basins with different paleoenvironmental regimes. Accumulation rates of phosphorus (P) bound to iron, organic matter, and authigenic phosphate are shown to rise and arrive at a distinct maximum at the onset of OAE 2, with an associated increase in δ13C values. Accumulation rates of...

Bibliothèque cantonale jurassienne

Spherule deposits in Cretaceous–Tertiary boundary sediments in Belize and Guatemala

Keller, Gerta

In: Journal of the Geological Society, 2003, vol. 160, p. 783

Bibliothèque cantonale jurassienne

Multiple impacts across the Cretaceous–Tertiary boundary

Keller, Gerta

In: Earth-science reviews : the international geological journal bridging the gap between research articles and textbooks, 2003, vol. 62, p. 327

Bibliothèque cantonale jurassienne

Biotic effects of impacts and volcanism

Keller, Gerta

In: Earth and planetary science letters, 2003, vol. 215, p. 249

Université de Neuchâtel

Cenomanian–Turonian and δ13C, and δ18O, sea level and salinity variations at Pueblo, Colorado

Keller, Gerta ; Berner, Zsolt ; Adatte, Thierry ; Stueben, Doris

In: Palaeogeography, Palaeoclimatology, Palaeoecology, 2004, vol. 211, no. 1-2, p. 19-43

Stable isotopes of the surface dwelling planktic foraminifera Hedbergella planispira, its abundance variations, and mineralogical analysis of the Cenomanian–Turonian at Pueblo, CO, reveal cyclic variations in surface salinity due to changes in precipitation, freshwater influx, marine incursions and long-term sea-level fluctuations. Hedbergella planispira is a proxy for salinity...

Université de Neuchâtel

Biotic effects of the Chicxulub impact, K–T catastrophe and sea level change in Texas

Keller, Gerta ; Abramovich, S. ; Berner, Zsolt ; Adatte, Thierry

In: Palaeogeography, Palaeoclimatology, Palaeoecology, 2009, vol. 271, no. 1-2, p. 52-68

Biotic effects of the Chicxulub impact, the K–T event and sea level change upon planktic foraminifera were evaluated in a new core and outcrops along the Brazos River, Texas, about 1000 km from the Chicxulub impact crater on Yucatan, Mexico. Sediment deposition occurred in a middle neritic environment that shallowed to inner neritic depths near the end of the Maastrichtian. The sea level fall...

Université de Neuchâtel

Oceanic events and biotic effects of the Cenomanian-Turonian anoxic event, Tarfaya Basin, Morocco

Keller, Gerta ; Adatte, Thierry ; Berner, Zsolt ; Chellai, E.H. ; Stueben, Doris

In: Cretaceous Research, 2008, vol. 29, no. 5-6, p. 976-994

Profound biotic changes accompanied the late Cenomanian δ13C excursion and OAE2 in planktic foraminifera in the Tarfaya Basin of Morocco. Planktic foraminifera experienced a severe turnover, though no mass extinction, beginning with the rapid δ13C excursion and accelerating with the influx of oxic bottom waters during the first peak and trough of the excursion. Species...

Université de Neuchâtel

Organic carbon deposition and phosphorus accumulation during Oceanic Anoxic Event 2 in Tarfaya, Morocco

Mort, Haydon P. ; Adatte, Thierry ; Keller, Gerta ; Bartels, David ; Föllmi, Karl B. ; Steinmann, Philipp ; Berner, Zsolt ; Chellai, E.H.

In: Cretaceous Research, 2008, vol. 29, no. 5-6, p. 1008-1023

With a multi-proxy approach, an attempt was made to constrain productivity and bottom-water redox conditions and their effects on the phosphorus accumulation rate at the Mohammed Plage section on the Tarfaya coast, Morocco, during the Cenomanian-Turonian Anoxic Event (OAE 2). A distinct δ13Corg isotope excursion of +2.5‰ occurs close to the top of the section. The...

See also: similar author names
1 Keller, Greta
4 Keller, Guillaume