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  • 1
    In: Tectonophysics, Amsterdam [u.a.] : Elsevier, 1964, 448(2008), Seite 77-97, 1879-3266
    In: volume:448
    In: year:2008
    In: pages:77-97
    Description / Table of Contents: The electron backscattering diffraction technique (EBSD) was used to analyze bulging recrystallization microstructures from naturally and experimentally deformed quartz aggregates, both of which are characterized by porphyroclasts with finely serrated grain boundaries and grain boundary bulges set in a matrix of very fine recrystallized grains. For the Tonale mylonites we investigated, a temperature range of 300-380ʿC, 0.25 GPa confining pressure, a flow stress range of ~0.10.2 GPa, and a strain rate of ~10-13 s-1 were estimated. Experimental samples of Black Hills quartzite were analyzed, which had been deformed in axial compression at 700ʿC, 1.21.5 GPa confining pressure, a flow stress of ~0.3 0.4 GPa, a strain rate of ~10-6 s-1, and to 44% to 73% axial shortening. Using orientation imaging we investigated the dynamic recrystallization microstructures and discuss which processes may contribute to their development. Our results suggest that several deformation processes are important for the dismantling of the porphyroclasts and the formation of recrystallized grains. Grain boundary bulges are not only formed by local grain boundary migration, but they also display a lattice misorientation indicative of subgrain rotation. Dynamic recrystallization affects especially the rims of host porphyroclasts with a hard orientation, i.e. with an orientation unsuitable for easy basal slip. In addition, Dauphiné twins within porphyroclasts are preferred sites for recrystallization. We interpret large misorientation angles in the experimental samples, which increase with increasing strain, as formed by the activity of fluid-assisted grain boundary sliding.
    Type of Medium: Online Resource
    Pages: Ill., graph. Darst., Kt
    ISSN: 1879-3266
    Language: English
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  • 2
  • 3
    Keywords: Konferenzschrift
    Type of Medium: Book
    Pages: 119 S. , Ill., graph. Darst., Kt.
    Series Statement: Tectonics, Structural Geology and Geology of Crystalline Rocks [1]
    Language: English , German
    Note: Text teilw. engl., teilw. dt.
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  • 4
    Book
    Book
    Kiel : The Future Ocean
    Type of Medium: Book
    Pages: 52 S. , zahlr. Ill.
    Series Statement: Tectonics, Structural Geology and Geology of Crystalline Rocks [2]
    Language: German
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  • 5
    Keywords: Geography ; Oceanography ; Sedimentology ; Physical geography ; Konferenzschrift ; Aufsatzsammlung ; Meereskunde ; Massenbewegung
    Description / Table of Contents: Submarine mass movements are a hidden geohazard with large destructive potential for submarine installations and coastal areas. This hazard and associated risk is growing in proportion with increasing population of coastal urban agglomerations, industrial infrastructure, and coastal tourism. Also, the intensified use of the seafloor for natural resource production, and deep sea cables constitutes an increasing risk. Submarine slides may alter the coastline and bear a high tsunamogenic potential. There is a potential link of submarine mass wasting with climate change, as submarine landslides can uncover and release large amounts greenhouse gases, mainly methane, that are now stored in marine sediments. The factors that govern the stability of submarine slopes against failure, the processes that lead to slope collapses and the collapse processes by themselves need to be better understood in order to foresee and prepare society for potentially hazardous events. This book volume consists of a collection of cutting edge scientific research by international experts in the field, covering geological, geophysical, engineering and environmental aspects of submarine slope failures. The focus is on understanding the full spectrum of challenges presented by this major coastal and offshore geohazard
    Type of Medium: Book
    Pages: XVI, 683 S. , Ill., graph. Darst., Kt.
    ISBN: 9783319009711
    Series Statement: Advances in natural and technological hazards research 37
    DDC: 551.46
    Language: English
    Note: Literaturangaben , Physical properties of sedimentsGas hydrates and role of interstitial fluids in submarine slope failure -- Slope stability and risk assessment -- Monitoring, observation and repeated surveys of active slope failure processes -- Understanding failure processes from submarine landslide geomorphology -- Interaction between ocean circulation and MTDs -- Landslide generated tsunamis -- Long-term record of submarine landslides and MTD paleoseismology -- Outcrops of ancient submarine landslides.
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  • 6
    Online Resource
    Online Resource
    Cham :Springer International Publishing AG,
    Keywords: Mass-wasting. ; Electronic books.
    Description / Table of Contents: This book covers the geological, geophysical, engineering and environmental aspects of submarine slope failures. It focuses on understanding the full spectrum of challenges presented by this major coastal and offshore geohazard.
    Type of Medium: Online Resource
    Pages: 1 online resource (664 pages)
    Edition: 1st ed.
    ISBN: 9783319009728
    Series Statement: Advances in Natural and Technological Hazards Research Series ; v.37
    DDC: 551.468
    Language: English
    Note: Intro -- Preface -- Contents -- Part I Physical Properties of Sediments -- Chapter 1: Weak Layers: Their Definition and Classification from a Geotechnical Perspective -- 1.1 Introduction -- 1.2 Weak Layer Definition -- 1.3 Weak Layer Observations -- 1.4 Classification System from a Geotechnical Approach -- 1.5 Concluding Remarks -- References -- Chapter 2: Field Measurements to Investigate Submerged Slope Failures -- 2.1 Introduction -- 2.2 Interpretation Methods of Field Measurements -- 2.2.1 Relative Density -- 2.2.2 State Parameter -- 2.3 Application on Test Locations -- 2.4 Discussion -- 2.5 Conclusions and Recommendations -- References -- Chapter 3: Elemental Distribution and Microfabric Characterization Across a Buried Slump Scar: New Insights on the Long-Term Development and Reactivation of Scar Surfaces from a Microscopic Perspective -- 3.1 Introduction -- 3.2 Geological Setting -- 3.3 Investigation of Remineralization at the Unconformity -- 3.3.1 X-ray Computed Tomography (X-CT) -- 3.3.2 X-ray Fluorescence Spectroscopy (XRF) -- 3.3.3 Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Analysis (EDX) -- 3.4 Discussion and Conclusion -- References -- Chapter 4: Evidence for Mass Transport Deposits at the IODP JFAST-Site in the Japan Trench -- 4.1 Introduction -- 4.2 Background and Geological Setting -- 4.3 Material and Methods -- 4.3.1 Bathymetric Mapping -- 4.3.2 Sediment Core -- 4.3.2.1 Physical Properties -- 4.3.2.2 Pore-Water Analyses -- 4.4 Results -- 4.5 Discussion -- 4.5.1 Evidencing Mass Transport Deposits at the JFAST-Site -- 4.5.2 Estimating the Age of the MTD Formation -- 4.6 Conclusions -- References -- Chapter 5: Preliminary Investigations of Rheological Properties of Busan Clays and Possible Implications for DebrisFlow Modelling -- 5.1 Introduction -- 5.2 Materials and Methods -- 5.3 Results. , 5.3.1 Rheological Behaviour of the Busan Clays -- 5.4 Discussion -- 5.5 Conclusions -- References -- Chapter 6: Utilizing Cone Penetration Tests for Landslide Evaluation -- 6.1 Introduction -- 6.2 Site Characterization -- 6.3 Methods -- 6.3.1 In-Situ CPT Measurements -- 6.3.2 Physical and Mechanical Properties -- 6.4 Results and Discussion -- 6.4.1 Static CPT -- 6.4.2 Vibratory CPT -- 6.4.3 Dissipation Test -- 6.4.4 Liquefaction Analysis with CLiq Software -- 6.5 Summary and Conclusion -- References -- Chapter 7: Geomechanical Characterization of Submarine Volcano-Flank Sediments, Martinique, Lesser Antilles Arc -- 7.1 Introduction -- 7.2 Geomechanical Characterization -- 7.3 Results -- 7.3.1 Summary of Hole Stratigraphy -- 7.3.2 Consolidation State -- 7.3.3 Hydraulic Conductivity -- 7.4 Discussion and Conclusion -- References -- Part II Gas Hydrates and Role of Interstitial Fluids in Submarine Slope Failure -- Chapter 8: Interrelationship Between Sediment Fabric, Pore Volume Variations as Indicator for Pore Pressure Changes, and Sediment Shear Strength -- 8.1 Introduction -- 8.2 Method -- 8.3 Results -- 8.4 Discussion -- 8.4.1 Interplay: Sediment Strength and Pore Volume Changes -- 8.4.1.1 Effect of Grain Shape Complexity -- 8.4.2 Local Pore Volume Changes -- 8.5 Conclusions -- References -- Chapter 9: Slope Instability of Glaciated Continental Margins: Constraints from Permeability-Compressibility Tests and Hydrogeological Modeling Off Storfjorden, NW Barents Sea -- 9.1 Introduction -- 9.2 Data and Methods -- 9.3 Results -- 9.4 Discussion -- 9.5 Conclusions -- References -- Chapter 10: Baiyun Slide and Its Relation to Fluid Migration in the Northern Slope of Southern China Sea -- 10.1 Introduction -- 10.2 Geological Setting -- 10.3 Data and Methods -- 10.4 Results -- 10.4.1 Morphology and Distribution of Baiyun Slide. , 10.4.2 Seismic Indications of Gas and Fluid Migration -- 10.4.2.1 Active Faults Related to Gas and Fluid Migration -- 10.4.2.2 Gas Chimneys -- 10.5 Discussion -- 10.5.1 Relationship Between Fluid Migration and Slope Stability -- 10.5.2 Possible Trigger Mechanisms -- 10.6 Conclusions -- References -- Chapter 11: Post-failure Processes on the Continental Slope of the Central Nile Deep-Sea Fan: Interactions Between Fluid Seepage, Sediment Deformation and Sediment-Wave Construction -- 11.1 Introduction -- 11.2 Methods -- 11.3 Results -- 11.3.1 Architecture and Age of MTDs and Slope Deposits -- 11.3.2 Seabed Sediment Undulations -- 11.3.3 Sediment Pathways -- 11.4 Discussion -- 11.4.1 End-Members: Sediment Waves Versus Deformation Structures -- 11.4.2 Post-failure Slope Evolution -- 11.5 Conclusion -- References -- Chapter 12: Fluid Seepage in Relation to Seabed Deformation on the Central Nile Deep-Sea Fan, Part 1: Evidence from Sidescan Sonar Data -- 12.1 Introduction -- 12.2 Methods -- 12.3 Results -- 12.3.1 Erosional Furrows -- 12.3.2 Sediment Cracks -- 12.3.3 Carbonate Pavements -- 12.3.4 Hydroacoustic Flares -- 12.4 Discussion -- 12.4.1 Mid-slope Domain: Focused Fluid Flow Through MTDs -- 12.4.2 Western Undulations: Fluid Flow Along Faults Rooted in MTDs -- 12.4.3 Eastern Undulations: Exhumation of Fossil Carbonates -- 12.5 Conclusions -- References -- Chapter 13: Fluid Seepage in Relation to Seabed Deformation on the Central Nile Deep-Sea Fan, Part 2: Evidence from Multibeam and Sidescan Imagery -- 13.1 Introduction -- 13.2 Methods -- 13.3 Results -- 13.3.1 Faults and Fluid Indicators on Sub-bottom Profiles -- 13.3.2 Seabed Backscatter Anomalies at Differing Frequencies -- 13.3.3 Water Column Gas Flares -- 13.4 Discussion -- 13.4.1 Growth and Burial of Carbonate Pavements -- 13.4.2 Fluid Migration Along Fault Planes -- 13.5 Conclusions -- References. , Part III Slope Stability and Risk Assessment -- Chapter 14: Advances in Offshore Seismic Slope Stability: A Case History -- 14.1 Introduction -- 14.2 Geomorphological and Geotechnical Data -- 14.2.1 Site Investigations -- 14.2.2 Geomorphological Setting -- 14.2.3 Geotechnical and Geophysical Data Integration -- 14.2.4 Soil Sampling -- 14.2.5 Advanced Laboratory Testing -- 14.3 Stability Analyses -- 14.3.1 Conventional Approach -- 14.3.2 Dynamic Approach -- 14.4 Conclusions -- References -- Chapter 15: Size-Frequency Relationship of Submarine Landslides at Convergent Plate Margins: Implications for Hazard and Risk Assessment -- 15.1 Introduction -- 15.2 Tectonic Setting of the MA and CC Convergent Margins -- 15.3 MA and CC Slumps and Slides: Observations and Data -- 15.4 Size-Frequency Relationships -- 15.5 Discussion and Conclusion -- References -- Chapter 16: A Numerical Investigation of Sediment Destructuring as a Potential Globally Widespread Trigger for Large Submarine Landslides on Low Gradients -- 16.1 Introduction -- 16.1.1 Destructuring of Cemented Hemipelagic Clay as a Source of Overpressure -- 16.1.2 Aims and Approach -- 16.2 Methodology -- 16.2.1 Material Model -- 16.2.2 Model Description -- 16.2.3 Assumptions and Limitations -- 16.3 Results -- 16.4 Discussion -- 16.5 Conclusion -- References -- Chapter 17: How Stable Is the Nice Slope? - An Analysis Based on Strength and Cohesion from Ring Shear Experiments -- 17.1 Introduction and Geological Setting -- 17.2 Methods -- 17.2.1 Coring and Sedimentological Analysis -- 17.2.2 Shear Experiments with the Ring Shear Apparatus -- 17.2.3 Stability Assessment of the Nice Slope Sediments -- 17.3 Results -- 17.3.1 Sedimentological Analysis and Physical Properties -- 17.3.2 Frictional Behavior of the Nice Slope Sediments -- 17.3.3 Stability Assessment of the Nice Slope Sediments -- 17.4 Discussion. , References -- Chapter 18: Regional Slope Stability Assessment Along the Caucasian Shelf of the Black Sea -- 18.1 Introduction -- 18.2 Geological Engineering Conditions Along the Caucasian Shelf of the Black Sea -- 18.3 Methods -- 18.4 Regional Submarine Slope Stability Assessment Based on 1D Modelling -- 18.5 Local Submarine Slope Stability Assessment Based on 1D Modelling -- 18.5.1 Dzhubga -- 18.5.2 Novomikhailovsky -- 18.5.3 Tuapse -- 18.5.4 Ashe -- 18.5.5 Shahe -- 18.5.6 Dagomis -- 18.5.7 Kudepsta -- 18.6 Discussion and Conclusion -- References -- Chapter 19: A Semi-empirical Method to Assess Flow-Slide Probability -- 19.1 Introduction -- 19.2 Failure Mechanisms -- 19.2.1 Static Liquefaction -- 19.2.2 Breach Flow-Slide -- 19.3 Physical-Based Models -- 19.3.1 Static Liquefaction -- 19.3.2 Breach Flow-Slide -- 19.3.3 Applicability of Physical-Based Models -- 19.4 Empirical Method -- 19.4.1 Basic Information and Mean Flow-Slide Frequency -- 19.4.2 General Applicability to Other Regions in the Netherlands -- 19.4.3 Influence of Local Soil Characteristics and Slope Geometry -- 19.5 Semi-empirical Method -- 19.5.1 Determination of P(ZVliquefaction) -- 19.5.2 Determination of P(ZVbreachflow) -- 19.6 Concluding Remarks -- References -- Chapter 20: Submarine Slope Stability Assessment of the Central Mediterranean Continental Margin: The Gela Basin -- 20.1 Introduction -- 20.2 Geological Setting -- 20.3 Material and Methods -- 20.3.1 Shipboard and Laboratory Analysis -- 20.3.2 Overpressure Estimation -- 20.3.3 Slope Stability Analysis -- 20.4 Results -- 20.4.1 Physical and Geotechnical Properties -- 20.4.2 Slope Stability Analysis -- 20.5 Discussion -- 20.5.1 Preconditioning Factors -- 20.5.2 Triggering Factors -- 20.6 Conclusions -- References -- Part IV Monitoring, Observation and Repeated Surveys of Active Slope Failure Processes. , Chapter 21: The 1930 Landslide in Orkdalsfjorden: Morphology and Failure Mechanism.
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  • 7
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    Unknown
    PANGAEA
    In:  Supplement to: Völker, David; Stipp, Michael (2015): Water input and water release from the subducting Nazca Plate along southern Central Chile (33°S-46°S). Geochemistry, Geophysics, Geosystems, 16(6), 1825-1847, https://doi.org/10.1002/2015GC005766
    Publication Date: 2023-10-28
    Description: The age of the subducting Nazca Plate off Chile increases northwards from 0 Ma at the Chile Triple Junction (46°S) to 37 Ma at the latitude of Valparaíso (32°S). Age-related variations in the thermal state of the subducting plate impact on (a) the water influx to the subduction zone, as well as on (b) the volumes of water that are released under the continental forearc or, alternatively, carried beyond the arc. Southern Central Chile is an ideal setting to study this effect, because other factors for the subduction zone water budget appear constant. We determine the water influx by calculating the crustal water uptake and by modeling the upper mantle serpentinization at the outer rise of the Chile Trench. The water release under forearc and arc is determined by coupling FEM thermal models of the subducting plate with stability fields of water-releasing mineral reactions for upper and lower crust and hydrated mantle. Results show that both the influx of water stored in, and the outflux of water released from upper crust, lower crust and mantle vary drastically over segment boundaries. In particular, the oldest and coldest segments carry roughly twice as much water into the subduction zone as the youngest and hottest segments, but their release flux to the forearc is only about one fourth of the latter. This high variability over a subduction zone of 〈 1500 km length shows that it is insufficient to consider subduction zones as uniform entities in global estimates of subduction zone fluxes. This article is protected by copyright. All rights reserved.
    Keywords: Center for Marine Environmental Sciences; Comment; File format; File name; GEOMAR; Helmholtz Centre for Ocean Research Kiel; MARUM; SFB574; Uniform resource locator/link to graphic; Volatiles and Fluids in Subduction Zones
    Type: Dataset
    Format: text/tab-separated-values, 12 data points
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  • 8
    Publication Date: 2021-03-29
    Description: Since the work of Griggs & Blacic (1965) it is well known that the crystal plastic flow strength of ‘wet’ quartz samples is much lower than that of ‘dry’ samples deformed at the same conditions, and the general effect of water on dislocation creep microstructures has been documented (e.g. Hirth & Tullis 1992), but its effect on the recrystallized grain size has not been quantified. The recrystallized grain size is the most reliable and most easily measurable microstructural feature to derive flow stresses from natural mylonites (e.g. White 1979, Kohlstedt et al. 1980). In a recent experimental study, a well-constrained recrystallized grain size piezometer for quartz (Stipp & Tullis 2003) was calibrated using natural as-is quartzites; the use of a molten salt cell at high confining pressure (1.5GPa) in a Griggs-type apparatus allowed good stress resolution (Green & Borch 1989). There has been some debate as to whether there is any independent effect of water on the recrystallized grain size piezometer. Two laboratory studies on olivine aggregates (at different pressures) report contradictory results; van der Wal et al. (1993) found that the recrystallized grain size piezometer is independent of the water content, whereas Jung & Karato (2001) observed a water-dependence of the piezometer. In this study, we have investigated changes in the recrystallized grain size and other deformation microstructures of quartz within dislocation creep regimes 2 and 3 of Hirth & Tullis (1992). Deformation experiments on Black Hills quartzite with three different initial water contents (as-is, wateradded and vacuum-dried) were carried out in order to evaluate the effect of water on the recrystallized grain size / flow stress piezometer...
    Description: conference
    Keywords: 551 ; VKA 200 ; VAE 120 ; VAE 140 ; VHB 400 ; VKA 120 ; VKB 270 ; Gefügekunde der Gesteine ; Methodik {Strukturgeologie} ; Gesteinsdeformation {Strukturgeologie} ; Oxide und Hydroxide {Mineralogie} ; Experimentelle Petrologie ; Produkte mechanischer Deformation {Petrologie} ; Quarzit ; Deformation 〈Geologie〉 ; Experiment ; Quarz ; Rekritallisationstextur
    Language: German
    Type: anthologyArticle , publishedVersion
    Format: application/pdf
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  • 9
    Publication Date: 2021-03-29
    Description: Das Untersuchungsgebiet umfasst den Nordrand des Aarmassivs, die autochthone und paraautochthone sedimentäre Bedeckung des Aarmassivs, den ultrahelvetischen Wildflysch und den Südrand der Wildhorndecke. Das Aarmassiv besteht aus dem Innertkirchener Granit und Granitgneis und den sogenannten Mischgneisen. Lokal sind präalpine mylonitische Scherzonen ausgebildet. Die sedimentäre Bedeckung des Aarmassivs beginnt mit einem geringmächtigen permotriassischen Aufarbeitungshorizont des kristallinen Untergrundes aus Quarz-Glimmerschiefern, Arkosen und Konglomeraten. Darüber folgt die mehrere hundert Meter mächtige mesozoische Abfolge. Im Arbeitsgebiet tritt an der Basis der massige, hell bis rötlichgelb verwitternde Rötidolomit hervor. Im Hangenden liegen die kalkigen Schichten des Doggers sowie das Argovien. Darüber folgen die mächtigen Kalkserien des Malms (Quintner Kalk) und der unteren Kreide (Oehrlikalk), welche die Steilwände der Engelhörner aufbauen. In den parautochthonen Schuppen auf der Nordseite der Engelhörner beginnt die Abfolge erst mit dem unteren Malm. Als jüngste Einheit treten dort allerdings auch Tertiäre Schichten auf, welche überwiegend aus kalkhaltigen Sandsteinen, Brekzien und Tonschiefern bestehen. Als nur wenige Meter mächtiger dunkler bis schwarzer, glimmerführender Tonschiefer ist der allochthone ultrahelvetische Wildflysch zwischen den parautochthonen Schuppen und der Wildhorndecke eingeklemmt. Die Wildhorndecke wird im Arbeitsgebiet von den Einheiten des Doggers aufgebaut. Die Zuordnung des Doggers zur Wildhorndecke ist allerdings nicht immer eindeutig. Westlich des Arbeitsgebietes in der Umgebung von Grindelwald werden Einheiten des Doggers z.T. auch dem Ultarhelvetikum zugerechnet (Günzler-Seiffert & Wyss 1938).Die lithologische Kartierung, aber auch die Zuordnung der Lithologien zu den tektonischen Einheiten basiert im Wesentlichen auf den ausgezeichneten Vorarbeiten (z.B. Arbenz & Müller 1920; Günzler-Seiffert & Wyss 1938; Müller 1938; Büchi 1980). Ziel unserer Untersuchungen ist es, die Kinematik sowie die relative zeitliche Abfolge der einzelnen Groß- und Kleinstrukturen genauer zu bestimmen und die strukturelle Gliederung des Arbeitsgebietes mit den von Burkhard (1988) definierten Deformationsphasen zu korrelieren...
    Description: conference
    Keywords: 551 ; VAE 811 ; VAE 400 ; VAE 150 ; VAE 140 ; VEB 168 ; Alpidische Orogene {Geologie} ; Tektogenese {Geologie} ; Strukturelle Erscheinungen {Strukturgeologie} ; Gesteinsdeformation {Strukturgeologie} ; Schweizer Alpen {Geologie} ; Aarmassiv ; Ultrahelvetikum ; Scherzone ; Tektogenese ; Deformation 〈Geologie〉
    Language: German
    Type: anthologyArticle , publishedVersion
    Format: application/pdf
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  • 10
    facet.materialart.
    Unknown
    AGU (American Geophysical Union) | Wiley
    In:  Journal of Geophysical Research: Solid Earth, 122 (7). 5306-5324 .
    Publication Date: 2020-02-06
    Description: Many blueschists and eclogites are inferred to have formed from oceanic basalts in subducted slabs. Knowledge of their elastic behaviour is essential for reconstructing the internal structure of subduction zones. The Cycladic Blueschist Unit, exposed on Syros Island (Greece), contains rocks belonging to an exhumed Tertiary subduction complex. They were possibly part of a subduction channel, a shear zone above the subducting slab in which exhumation is possible during subduction. Intense plastic deformation, forming crystallographic preferred orientations (CPO), accompanied blueschist and eclogite metamorphism. CPO of the constituent minerals in the collected samples was determined by time-of-flight neutron diffraction. Two samples are foliated fine-grained blueschists with strong CPO, rich in glaucophane, zoisite and phengite. Two coarser-grained eclogite samples rich in omphacite and clinozoisite, or glaucophane, have weaker CPO. Vp and Vs anisotropies were computed from the orientation distribution function and single-crystal elastic constants. All samples show velocity maxima parallel to the mineral lineation, and minima normal to the foliation, providing important constraints on orientations of seismic anisotropy in subduction channels. Vp anisotropies are up to three times higher (6.5-12%) in the blueschists than in the eclogites (3-4%), pointing to a potentially important lithological control of elastic anisotropy in subducted oceanic crust.
    Type: Article , PeerReviewed
    Format: text
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