Results 121 to 130 of about 66,997 (277)

Preconditioning and triggering of offshore slope failures and turbidity currents revealed by most detailed monitoring yet at a fjord-head delta [PDF]

, 2016
Rivers and turbidity currents are the two most important sediment transport processes by volume on Earth. Various hypotheses have been proposed for triggering of turbidity currents offshore from river mouths, including direct plunging of river discharge,
Cartigny, Matthieu J.B., Clare, Michael A., Hughes Clarke, John E., Pratomo, D. G., Talling, Peter J.   +4 more
core   +1 more source

A case for biotic morphogenesis of coniform stromatolites

, 2004
Mathematical models have recently been used to cast doubt on the biotic origin of stromatolites. Here by contrast we propose a biotic model for stromatolite morphogenesis which considers the relationship between upward growth of a phototropic or ...
Arp, B.I. Henry, Barabási, Batchelor, Bauld, Bertrand-Sarfati, Brasier, Buick, Burne, Cohen, Garcia-Ruiz, Grotzinger, Grotzinger, Hofmann, Horodyski, Kaandorp, Kardar, Knoll, Lobkovsky, Lowe, M.J. Jackson, M.T. Batchelor, Maslov, R.V. Burne, Schopf, Verrecchia, Wainwright, Walter, Witten   +28 more
core   +1 more source

Confirmation of the impact origin of the Late Ordovician Tvären impact structure (southeast Sweden) and emplacement of impactites in a marine setting

Meteoritics &Planetary Science, EarlyView.
Abstract The Tvären structure in southeastern Sweden has been listed as a confirmed marine‐target impact structure for decades. However, to date, no measurements and/or indexed data of planar deformation features in quartz grains from the structure have been published or any other unequivocal evidence of impact.
Katarzyna J. Gajewska, Sanna Alwmark, Mikael Calner, Sylvain Richoz, Jens Ormö, Erik Sturkell, Carl Alwmark   +6 more
wiley   +1 more source

The apparent roughness of a sand surface blown by wind from an analytical model of saltation

, 2012
We present an analytical model of aeolian sand transport. The model quantifies the momentum transfer from the wind to the transported sand by providing expressions for the thickness of the saltation layer and the apparent surface roughness.
, Bagnold R A, Durán O, H J Herrmann, J F Kok, Julien P Y, Keulegan G H, Kok J F Parteli E J R Michaels T I Karam D B, Leal L G, Nikuradse J, Nikuradse J, Prandtl L, T Pähtz   +12 more
core   +1 more source

Bio‐mediated cementation of supratidal beach sediments associated with groundwater springs

Sedimentology, EarlyView.
ABSTRACT The formation of beachrock, sensu stricto, via carbonate precipitation in the intertidal zone is widespread throughout the tropics and subtropics. While cementation of supratidal beach sediments has also been noted in several locations, it has received much less attention.
Thomas William Garner, J. Andrew G. Cooper   +1 more
wiley   +1 more source

Microbial influence on the formation and subsequent changes of vertebrate tracks: field experiments on present‐day coastal sediments

Sedimentology, EarlyView.
ABSTRACT The presence of microbial mats is often invoked to explain the good preservation of vertebrate tracks, because they can cover and biostabilize such structures. However, microbial influence on the sediment properties when the track is made and on the track characteristics has not been so thoroughly analysed.
Isabel Emma Quijada, Lucía Maisano, Jerónimo Pan, María Florencia Yorlano, Diana G. Cuadrado   +4 more
wiley   +1 more source

Sedimentary lithofacies, petrography and diagenesis of the Kapuni group in the Kapuni Field, Taranaki Basin, New Zealand : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science with Honours in Earth Science at Massey University, Palmerston North, New Zealand [PDF]

, 2004
The reservoir architecture and quality of the Kapuni Group sandstones in seven wells (Kapuni−1, −3, −8, −12, Deep−1, 14 and −15) in the Kapuni Field are characterised using available core and digital geophysical log data.
Cooper, Brent John
core  

Microbial mats in dinosaur ichnocoenoses

Sedimentology, EarlyView.
ABSTRACT Until now, the significance of microbial mats in preservation of dinosaur tracks and in reconstructing the palaeoenvironment in which dinosaurs roamed was rarely studied. Dinosaur tracks are commonly found close to ancient aquatic bodies where moist sediment had once allowed footstep registration.
Nora Noffke, Paul C. Murphey, Roger C. Buntin, Martin G. Lockley   +3 more
wiley   +1 more source

Microbial mats and thalassinid shrimp: Spatial and geochemical interactions in a modern intertidal environment

Sedimentology, EarlyView.
ABSTRACT This research examines the spatial and geochemical interactions between mat‐forming microorganisms and thalassinid shrimp in an intertidal flat situated on the shores of Willapa Bay, Washington, USA. The study serves as a contemporary analog for the relationships between mats and burrowing organisms in deep time.
Brette S. Harris, Sara K. Biddle, Maya T. LaGrange, Scott Melnyk, Cody N. Lazowski, Jenifer S. Spence, Daniel Alessi, Jeffrey Kavanaugh, Kurt O. Konhauser, Murray K. Gingras   +9 more
wiley   +1 more source

Microbially generated ferruginous crusts: A potential biosignature of continental input in coastal settings

Sedimentology, EarlyView.
ABSTRACT Thin ferruginous sandy crusts are common on top of sandstone beds in the Early Permian post‐glacial deposits of the Paraná Basin in southern Brazil. These crusts usually preserve wrinkle structures, suggesting that they might be a product of microbial mediation.
Patrícia Weschenfelder, Renata Guimarães Netto, Alisson Klayton Martins   +2 more
wiley   +1 more source