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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...

Université de Neuchâtel

Phosphogenesis and organic-carbon preservation in the Miocene Monterey Formation at Naples Beach, California—The Monterey hypothesis revisited

Föllmi, Karl B. ; Badertscher, Christophe ; de Kaenel, Eric ; Stille, Peter ; John, Cédric M. ; Adatte, Thierry ; Steinmann, Philipp

In: GSA Bulletin, 2005, vol. 117, no. 5-6, p. 589-619

The middle part of the Miocene Monterey Formation at Naples Beach, west of Santa Barbara, California, is predominantly composed of organic-rich mudstone interstratified with phosphatic laminae. Minor lithologies include volcanic ash, dolomite, porcelanite and chert, and condensed phosphatic beds. Sediments dated as 14.3–13.5 Ma have average total organic carbon (TOC) values around 8.5 wt%, and...

Université de Neuchâtel

Carbonaceous and Phosphate-Rich Sediments of the Miocene Monterey Formation at El Capitan State Beach, California, U.S.A.

John, Cédric M. ; Föllmi, Karl B. ; De Kaenel, Eric ; Adatte, Thierry ; Steinmann, Philipp ; Badertscher, Christophe

In: Journal of Sedimentary Research, 2002, vol. 72, no. 2, p. 252-267

The organic- and phosphate-rich interval of the Monterey Formation at El Capitan State Beach (west of Santa Barbara, California, U.S.A.; late early to early late Miocene in age) is composed of a carbonaceous marl (TOC contents between 1.2 and 23.2 wt %) with intercalated phosphate-rich laminae, lenses, and layers. Subordinate lithologies include ash layers, dolomitized horizons, and siliceous...

Université de Fribourg

Paleocene–Eocene palaeoenvironmental conditions of the main phosphorite deposits (Chouabine Formation) in the Gafsa Basin, Tunisia

Kocsis, László ; Ounis, Anouar ; Baumgartner, Claudia ; Pirkenseer, Claudius ; Harding, Ian C. ; Adatte, Thierry ; Chaabani, Fredj ; Neili, Salah Mohamed

In: Journal of African Earth Sciences, 2014, vol. 100, p. 586–597

A detailed sedimentary section of the marine Chouabine Formation in the palaeogeographic Gafsa Basin, south-western Tunisia, was investigated in order to characterize environmental and depositional conditions focusing on the interval that spans the Paleocene–Eocene transition. We did stable isotope analyses of bulk sediments. Both phosphorite and carbonate yielded relatively similar isotopic...