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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

Glarus overthrust: A major pathway for the escape of fluids out of the Alpine orogen

Badertscher, Nicolas P. ; Beaudoin, Georges ; Therrien, René ; Burkhard, Martin

In: Geology, 2001, vol. 30, no. 10, p. 875-878

Thrust-related fluid flow coupled with isotopic exchange between fluid and rock is simulated in a three-dimensional finite-element model of the Glarus nappe, eastern Swiss Alps. Numerical simulations are matched against well-established oxygen isotope gradients on the kilometer scale along the thrust. At internal southern locations, strongly channelized thrust-parallel fluid flow requires a high...

Université de Neuchâtel

Near vertical iso-illite-crystallinity surfaces cross-cut the recumbent fold structure of the Morcles nappe, Swiss Alps

Burkhard, Martin ; Goy-Eggenberger, D.

In: Clay Minerals, 2001, vol. 36, p. 159-170

Metamorphic isograd surfaces are mapped within the Morcles nappe using illite crystallinity (IC) and (clay-) mineral parageneses in 268 samples. The diagenesis-anchizone and the anchizone-epizone boundaries are nearly vertical surfaces which crosscut the present-day recumbent fold nappe structure. Frontal parts of the nappe are diagenetic (Tmax <200°C) whereas rear parts both...

Université de Neuchâtel

Finite strain has no influence on the illite crystallinity of tectonized Eocene limestone breccias of the Morcles nappe, Swiss Alps

Burkhard, Martin ; Badertscher, Nicolas P.

In: Clay Minerals, 2001, vol. 36, p. 171-180

The relationship between illite crystallinity (IC) and finite strain as well as lattice strain and crystallite size of illite is examined in a series of 27 deformed breccia samples from the inverted limb of the Morcles nappe. The IC is determined independently for limestone components and a red/green clay-silt matrix. The finite strain varies widely (D = 0.8ÿ2.5). The IC values vary from...

Université de Neuchâtel

The challenge of soil erosion management in Switzerland : a socio-anthropological analysis of public policy construction and implementation

Derungs, Nicolas ; Hertz, Ellen

In: Bulletin BGS, 2016, vol. 37, p. 25-33

En 2014, le « Rapport agricole » annonce que la fertilité des sols agricoles suisses est compromise à long terme, et que l’une des causes principales est l’érosion hydrique. Le problème de l’érosion des sols n’est pourtant pas récent. Il est étudié depuis plus de cinquante ans et intégré dans des politiques agro-environnementales depuis plus de vingt ans. Or, malgré des...

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...

Accès public à partir du 7 juin 2018
Université de Neuchâtel

Augusto Palmonari

Baucal, Aleksandar ; Carugati, Felice ; Perret-Clermont, Anne-Nelly

In: European Journal of Psychology of Education, 2017, vol. 32, no. 3, p. 333-334

Université de Neuchâtel

Bacterially Induced Mineralization of Calcium Carbonate in Terrestrial Environments: The Role of Exopolysaccharides and Amino Acids

Braissant, Olivier ; Cailleau, Guillaume ; Dupraz, Christophe ; Verrecchia, Eric P.

In: Journal of Sedimentary Research, 2003, vol. 73, no. 3, p. 485-490

This study stresses the role of specific bacterial outer structures (such as glycocalix and parietal polymers) on calcium carbonate crystallization in terrestrial environments. The aim is to compare calcium carbonate crystals obtained in bacterial cultures with those obtained during abiotically mediated synthesis to show implications of exopolysaccharides and amino acids in the mineralogy and...