Journal ArticleDOI
North American lithospheric discontinuity structure imaged by Ps and Sp receiver functions
David L. Abt,David L. Abt,Karen M. Fischer,S. W. French,S. W. French,Heather A. Ford,Huaiyu Yuan,Barbara Romanowicz +7 more
TLDR
In this article, the authors used 93 permanent seismic stations to image upper mantle velocity discontinuities across the contiguous United States and portions of southeast Canada and northwest Mexico, using frequency-domain deconvolution and migrated with 1D models that account for variations in crustal structure and mantle velocities between stations.Abstract:
[1] Sp and Ps converted seismic waves at 93 permanent seismic stations are used to image upper mantle velocity discontinuities across the contiguous United States and portions of southeast Canada and northwest Mexico. Receiver functions are calculated with frequency-domain deconvolution and migrated with 1D models that account for variations in crustal structure and mantle velocities between stations. Strong positive Ps phases from the Moho are observed and agree well with previous crustal thickness estimates. In the tectonically active western U.S., high amplitude, negative Sp phases are interpreted as the lithosphere-asthenosphere boundary (LAB) at depths of 51–104 km. These phases indicate a large and rapid LAB velocity gradient and are consistent with an anomalously hot asthenosphere that is rich in water or contains partial melt. In the regions of the Phanerozoic southern and eastern U.S where Sp phases are interpretable as the LAB, the discontinuity lies at depths of 75–111 km and is also too sharp to be explained by temperature alone. In contrast, no Sp phases are observed at depths comparable to the base of the thick high velocity lithosphere that lies beneath cratonic North America and certain portions of the Phanerozoic eastern U.S. At these stations, negative Sp phases occur at depths of 59–113 km and are interpreted as the top of a low velocity zone internal to the lithosphere. The absence of an observable LAB discontinuity in regions of thick lithosphere indicates that the LAB velocity gradient is distributed over more than 50–70 km in depth and is consistent with a purely thermal boundary.read more
Citations
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Journal ArticleDOI
Lithospheric layering in the North American craton
Huaiyu Yuan,Barbara Romanowicz +1 more
TL;DR: It is shown that changes in the direction of azimuthal anisotropy with depth reveal the presence of two distinct lithospheric layers throughout the stable part of the North American continent and suggests that the horizon detected in receiver function studies probably corresponds to the sharp mid-lithospheric boundary rather than to the more gradual lithosphere–asthenosphere boundary.
Journal ArticleDOI
The Lithosphere- Asthenosphere Boundary
TL;DR: In this paper, a wide variety of studies are consistent with an oceanic lithosphere that corresponds to a dry, chemically depleted layer over a hydrated, fertile asthenosphere.
Journal ArticleDOI
On the origin of the asthenosphere
TL;DR: In this paper, a review of recent literatures shows that grain-size sensitive anelastic relaxation inevitably has two successive processes, high-frequency elastically accommodated grain-boundary sliding followed by low-frequency diffusion-accommodated aelasticity.
Journal ArticleDOI
Constraints on the shallow elastic and anelastic structure of Mars from InSight seismic data
Philippe Lognonné,Philippe Lognonné,William B. Banerdt,William T. Pike,Domenico Giardini,U. R. Christensen,Raphaël F. Garcia,Taichi Kawamura,Sharon Kedar,Brigitte Knapmeyer-Endrun,Ludovic Margerin,Francis Nimmo,Mark P. Panning,Benoit Tauzin,John-Robert Scholz,Daniele Antonangeli,S. Barkaoui,Eric Beucler,Felix Bissig,Nienke Brinkman,Marie Calvet,Savas Ceylan,Constantinos Charalambous,Paul M. Davis,M. van Driel,Mélanie Drilleau,Lucile Fayon,Rakshit Joshi,B. Kenda,Amir Khan,Amir Khan,Martin Knapmeyer,Vedran Lekic,J. B. McClean,David Mimoun,Naomi Murdoch,Lu Pan,Clément Perrin,Baptiste Pinot,L. Pou,Sabrina Menina,Sebastien Rodriguez,Sebastien Rodriguez,Cedric Schmelzbach,Nicholas Schmerr,David Sollberger,Aymeric Spiga,Aymeric Spiga,Simon Stähler,Alexander E. Stott,Eléonore Stutzmann,Saikiran Tharimena,Rudolf Widmer-Schnidrig,Fredrik Andersson,Veronique Ansan,Caroline Beghein,Maren Böse,Ebru Bozdag,John Clinton,Ingrid Daubar,Pierre Delage,Nobuaki Fuji,Matthew P. Golombek,Matthias Grott,Anna Horleston,K. Hurst,Jessica C. E. Irving,A. Jacob,Jörg Knollenberg,S. Krasner,C. Krause,Ralph D. Lorenz,Chloé Michaut,Chloé Michaut,Robert Myhill,Tarje Nissen-Meyer,J. ten Pierick,Ana-Catalina Plesa,C. Quantin-Nataf,Johan O. A. Robertsson,L. Rochas,Martin Schimmel,Sue Smrekar,Tilman Spohn,Tilman Spohn,Nicholas A Teanby,Jeroen Tromp,J. Vallade,Nicolas Verdier,Christos Vrettos,Renee Weber,Don Banfield,E. Barrett,M. Bierwirth,S. B. Calcutt,Nicolas Compaire,Catherine L. Johnson,Catherine L. Johnson,Davor Mance,Fabian Euchner,L. Kerjean,Guenole Mainsant,Antoine Mocquet,J. A Rodriguez Manfredi,Gabriel Pont,Philippe Laudet,T. Nebut,S. de Raucourt,O. Robert,Christopher T. Russell,A. Sylvestre-Baron,S. Tillier,Tristram Warren,Mark A. Wieczorek,C. Yana,Peter Zweifel +115 more
TL;DR: In this paper, the authors measured the crustal diffusivity and intrinsic attenuation using multiscattering analysis and found that seismic attenuation is about three times larger than on the Moon, which suggests that the crust contains small amounts of volatiles.
Journal ArticleDOI
Experimental Study of the Brittle Behavior of Clay shale in Rapid Unconfined Compression
TL;DR: In this paper, a series of 19 unconfined uniaxial compression tests were performed utilizing servo-controlled testing procedures for the brittle failure characteristics of Opalinus Clay from the Mont Terri Underground Research Laboratory.
References
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