I12-JEEP: Joint Engineering, Environmental and Processing
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Johan
Lindgren
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Dean R.
Lomax
,
Robert-Zoltán
Szász
,
Miguel
Marx
,
Johan
Revstedt
,
Georg
Göltz
,
Sven
Sachs
,
Randolph G.
De La Garza
,
Miriam
Heingård
,
Martin
Jarenmark
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Kristina
Ydström
,
Peter
Sjövall
,
Frank
Osbæck
,
Stephen A.
Hall
,
Michiel
Op De Beeck
,
Mats E.
Eriksson
,
Carl
Alwmark
,
Federica
Marone
,
Alexander
Liptak
,
Robert
Atwood
,
Genoveva
Burca
,
Per
Uvdal
,
Per
Persson
,
Dan-Eric
Nilsson
Diamond Proposal Number(s):
[33954]
Open Access
Abstract: With their superficially shark-like appearance, the Mesozoic ichthyosaurs provide a classic illustration of major morphological adaptations in an ancestrally terrestrial tetrapod lineage following the invasion of marine habitats1,2,3. Much of what is known about ichthyosaur soft tissues derives from specimens with body outlines4,5,6. However, despite offering insights into aspects of biology that are otherwise difficult to envisage from skeletal evidence alone (such as the presence of a crescentic fluke), information on their soft parts has hitherto been limited to a taxonomically narrow sample of small- to dolphin-sized animals2,4,5,6. Here we report the discovery of a metre-long front flipper of the large-bodied Jurassic ichthyosaur Temnodontosaurus, including unique details of its soft-tissue anatomy. In addition to revealing a wing-like planform, the fossil preserves a serrated trailing edge that is reinforced by novel cartilaginous integumental elements, herein denominated chondroderms. We also document chordwise-parallel skin ornamentations and a protracted fleshy distal tip that presumably acted like a flexible winglet in life. By integrating morphological and numerical data, we show that the observed features probably provided hydroacoustic benefits, and conclude that the visually guided7,8 Temnodontosaurus relied on stealth while hunting in dim-lit pelagic environments. This unexpected combination of control surface modifications represents a previously unrecognized mode of concealment, and underscores the importance of soft-tissue fossils when inferring aspects of palaeoethology and predator–prey palaeoecology.
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Jul 2025
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I12-JEEP: Joint Engineering, Environmental and Processing
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Diamond Proposal Number(s):
[30380]
Open Access
Abstract: Third- and fourth-generation synchrotron light sources with high fluxes and beam energies enable the use of innovative X-ray translucent experimental apparatus. These experimental devices access geologically relevant conditions whilst enabling in situ characterization using the spatial and temporal resolutions accessible at imaging beamlines. Here, Heitt Mjölnir is introduced, a heated miniature triaxial rig based on the design of Mjölnir, but covering a wider temperature range and larger sample volume at similar pressure capacities. This device is designed to investigate coupled thermal, chemical, hydraulic and mechanical processes from grain to centimetre scales using cylindrical samples of 10 mm × 20 mm (diameter × length). Heitt Mjölnir can simultaneously reach confining (hydraulic) pressures of 30 MPa and 500 MPa of axial stress with independently controlled sample pore fluid pressure < 30 MPa. This internally heated apparatus operates to temperatures up to 573 K with a minimal vertical thermal gradient in the sample of <0.3 K mm−1. This new apparatus has been deployed in operando studies at the TOMCAT (Swiss Light Source), I12 JEEP (Diamond Light Source) and PSICHÉ (Synchrotron SOLEIL) beamlines for 4D X-ray microtomography with scan intervals of a few minutes. Heitt Mjölnir is portable and modular, allowing a wide range of 4D characterizations of low-grade metamorphism and deformational processes. It enables spatially and temporally resolved fluid–rock interaction studies at conditions of crustal reservoirs and is suitable for characterization of material properties in geothermal, carbonation or subsurface gas storage applications. Technical drawings and an operation guide are included in this publication.
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Dec 2023
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I12-JEEP: Joint Engineering, Environmental and Processing
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Diamond Proposal Number(s):
[22178]
Abstract: Fluid release from dehydration reactions is considered to have significant effects on the strength and dynamics of tectonic faults at convergent plate boundaries. It is classically assumed that the production of fluid leads to increased pore fluid pressures that perturb a fault's stress state and thereby facilitates and enhances deformation. This important assumption has never been supported by direct microstructural observations. Here, we investigate the role of gypsum dehydration in the deformation of evaporitic rocks using synchrotron-based time-resolved X-ray computed microtomography (4D) imaging. This approach enables the documentation of coupled chemical, hydraulic and mechanical processes on the grain scale. In our experiments with deforming halite-gypsum-halite sandwiches we observe that the fluid released by dehydrating gypsum accumulates at the gypsum-halite interface before a distributed hydraulic failure of the halite layer drains the fluid. From our observations we conclude that perceivedly impermeable halite layers in evaporites are unlikely to trap overpressured fluid, e.g., in thin-skinned tectonic detachment horizons. Moreover, as the hydraulic failure is diffuse and not localized, our experiments suggest that dehydration reactions alone may not explain intermediate depth seismicity in subduction zones. Our data demonstrate the significant potential that in-situ 4D imaging has for the grain-scale investigation of fundamental tectonic processes.
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Dec 2020
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I12-JEEP: Joint Engineering, Environmental and Processing
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Katherine J.
Dobson
,
Anja
Allabar
,
Eloise
Bretagne
,
Jason
Coumans
,
Mike
Cassidy
,
Corrado
Cimarelli
,
Rebecca
Coats
,
Thomas
Connolley
,
Loic
Courtois
,
Donald B.
Dingwell
,
Danilo
Di Genova
,
Benjamin
Fernando
,
Julie L.
Fife
,
Frey
Fyfe
,
Stephan
Gehne
,
Thomas
Jones
,
Jackie E.
Kendrick
,
Helen
Kinvig
,
Stephan
Kolzenburg
,
Yan
Lavallee
,
Emma
Liu
,
Edward W.
Llewellin
,
Amber
Madden-Nadeau
,
Kamel
Madi
,
Federica
Marone
,
Cerith
Morgan
,
Julie
Oppenheimer
,
Anna
Ploszajski
,
Gavin
Reid
,
Jenny
Schauroth
,
Christian M.
Schlepütz
,
Catriona
Sellick
,
Jérémie
Vasseur
,
Felix W.
Von Aulock
,
Fabian B.
Wadsworth
,
Sebastian
Wiesmaier
,
Kaz
Wanelik
Diamond Proposal Number(s):
[15898]
Open Access
Abstract: Many of the grand challenges in volcanic and magmatic research are focused on understanding the dynamics of highly heterogeneous systems and the critical conditions that enable magmas to move or eruptions to initiate. From the formation and development of magma reservoirs, through propagation and arrest of magma, to the conditions in the conduit, gas escape, eruption dynamics, and beyond into the environmental impacts of that eruption, we are trying to define how processes occur, their rates and timings, and their causes and consequences. However, we are usually unable to observe the processes directly. Here we give a short synopsis of the new capabilities and highlight the potential insights that in situ observation can provide. We present the XRheo and Pele furnace experimental apparatus and analytical toolkit for the in situ X-ray tomography-based quantification of magmatic microstructural evolution during rheological testing. We present the first 3D data showing the evolving textural heterogeneity within a shearing magma, highlighting the dynamic changes to microstructure that occur from the initiation of shear, and the variability of the microstructural response to that shear as deformation progresses. The particular shear experiments highlighted here focus on the effect of shear on bubble coalescence with a view to shedding light on both magma transport and fragmentation processes. The XRheo system is intended to help us understand the microstructural controls on the complex and non-Newtonian evolution of magma rheology, and is therefore used to elucidate the many mobilization, transport, and eruption phenomena controlled by the rheological evolution of a multi-phase magmatic flows. The detailed, in situ characterization of sample textures presented here therefore represents the opening of a new field for the accurate parameterization of dynamic microstructural control on rheological behavior.
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Sep 2020
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I15-Extreme Conditions
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Diamond Proposal Number(s):
[7616]
Abstract: We have studied by X-ray diffractometry the crystallographic orientation relationships (CORs) between magnesiochromite (mchr) inclusions and their diamond hosts in gem-quality stones from the mines Udachnaya (Siberian Russia), Damtshaa (Botswana) and Panda (Canada); in total 36 inclusions in 23 diamonds. In nearly half of the cases (n = 17), [111]mchr is parallel within error to [111]diamond, but the angular misorientation for other crystallographic directions is generally significant. This relationship can be described as a case of rotational statistical COR, in which inclusion and host share a single axis (1 df). The remaining mchr–diamond pairs (n = 19) have a random COR (2 df). The presence of a rotational statistical COR indicates that the inclusions have physically interacted with the diamond before their final incorporation. Of all possible physical processes that may have influenced mchr orientation, those driven by surface interactions are not considered likely because of the presence of fluid films around the inclusions. Mechanical interaction between euhedral crystals in a fluid-rich environment is therefore proposed as the most likely mechanism to produce the observed rotational COR. In this scenario, neither a rotational nor a random COR can provide information on the relative timing of growth of mchr and diamond. Some multiple, iso-oriented inclusions within single diamonds, however, indicate that mchr was partially dissolved during diamond growth, suggesting a protogenetic origin of these inclusions.
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Apr 2019
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Open Access
Abstract: In situ synchrotron X-ray radiography was used to observe the evolution of 2D pits growing at the edge of stainless steel foils in chloride solutions of varying concentrations under current and potential control. A method was developed for measuring the local anodic current density along the perimeter of pits from the rate of advance of the pit into the metal. Pit depth tends to increase with time with kinetics consistent with diffusion control (under a salt layer), whereas lateral development (on film-free surfaces) is influenced by solution conductivity. Perforated covers formed on pits control their growth and stability.
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Nov 2015
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I22-Small angle scattering & Diffraction
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Josh
Hammons
,
Alison
Davenport
,
Seyed
Ghahari
,
Mehdi
Monir
,
Jean-Philippe
Tinnes
,
Mahrez
Amri
,
Nicholas
Terrill
,
Federica
Marone
,
Rajmund
Mokso
,
Marco F.
Stampanoni
,
Trevor
Rayment
Abstract: Interfacial phenomena occurring during high metal dissolution rates, in an environment with diffusion-limited transport of dissolution products, have been investigated using time-resolved X-ray diffraction (XRD), small-angle X-ray scattering (SAXS) and fast radiography. Time resolved SAXS data reveal that highly anisotropic interfacial X-ray scattering always precedes salt nucleation. The correlation between the interfacial scattering the presence of salt crystals indicates that the interface is between the metal electrode and the concentrated NiCl2 electrolyte and can therefore be interpreted as reflectivity or Porod scattering. Using fast radiography, we show that continued crystal nucleation and growth results in formation of a crystal-containing salt layer, which initially extends far from the interface (>20 μm), until the NiCl2 concentration decreases below saturation. Dissolution of this thick salt layer occurs mainly at the furthest boundary from the interface until, the salt layer thickness decreases to a steady state value, resulting in a steady state limiting current. These results show that the presence of a crystalline salt layer at a dissolving interface causes microscopic roughening which has implications for understanding both the role of salt films in pitting corrosion and electrochemical processing
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Apr 2013
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Abstract: Pitting corrosion of stainless steel has been investigated with high-resolution in situ X-ray microtomography. The growth of pits at the tip of stainless steel pins has been observed with 3D microtomography under different conditions of applied current and cell potential. The results demonstrate how pits evolve in stainless steel, forming a characteristic lacy top of perforated metal. In addition, it is shown how the shape of pits becomes modified by MnS inclusions.
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May 2011
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S. M.
Ghahari
,
D. P.
Krouse
,
N. J.
Laycock
,
T.
Rayment
,
C.
Padovani
,
T.
Suter
,
R.
Mokso
,
F.
Marone
,
M.
Stampanoni
,
M.
Monir
,
A. J.
Davenport
Abstract: In situ synchrotron radiography has been used to observe the evolution of two-dimensional pits growing in stainless steel foils under electrochemical control in chloride solutions. A method for extracting the key kinetic parameters from radiographs is under development to provide data for validating and calibrating a two-dimensional finite element model previously developed by Laycock and White. The local current density along the boundary of a pit is directly measured from the radiographs. Then, the local metal ion concentration and potential drop inside the pit cavity are backcalculated using transport equations and the requirement to maintain charge neutrality, giving the relationship between current density, solution composition and interfacial potential. Preliminary comparisons show qualitative correlation between the model and extracted data; quantitative comparison is under way.
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Apr 2011
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