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The article delves into the history of the Lyonnaise textile manufacturer Chavent, Père et Fils, highlighting its collaboration with Maison Worth and the significant influence it had on couture during the late 19th and early 20th centuries. Topics include the exploration of Chavent's eclectic production, its pivotal role in the Fabrique Lyonnaise, and the evolution of its distinctive style through extensive archival research and analysis of extant garments.

Heterogeneities in the magnetic signature along intraplate shear zones complicate their correlation with the physical processes that are involved in the geodynamic evolution of megathrusts. Isolating the preferred orientation of different magnetic minerals may provide insights into faulting processes, tectonics, and strain partitioning. Studies of exhumed analogs are fundamental to constrain variations in the magnetic properties with respect to a geodynamic context of intraplate shear zones. This study uses a combined statistical and magnetic approach to separate the contribution of coexisting petrofabrics to better interpret the heterogeneities in the magnetic signature. The main results indicate that there is a strong dependency among the variation in the magnetic properties and their anisotropy with the distance from the thrust faults and strain localization within the shear zone. Close to the main thrust, we observed a shear‐related fabric, indicating a high degree of non‐coaxial strain. Away from the thrust faults, the degree of anisotropy and the ellipsoids' oblateness gradually diminishes and subfabrics related to previous tectonic events or less intense deformation become dominant. Our observations also indicate strain decoupling across the basal thrust with dominant vertical uniaxial strain within the footwall. In contrast characterization of the anisotropy of magnetic remanence provides significant information on the variable response of different subpopulations of ferromagnetic minerals to shearing, indicating different degree of reworking or independent deformation processes. Plain Language Summary: Giant earthquakes commonly occur at active intraplate zones and to understand their formation and propagation, it is necessary to understand how rocks deform at intraplate shear zones. Variations in physical and rheological properties as well as fluids pressures are significant in controlling the seismicity. The directional variations of the magnetic properties of rocks strongly depends on these properties. This use of magnetic fabrics has been largely applied to convergent margins and mountain chains, but studies on intraplate shear zones that involve heterogeneous materials have been less studied. Our approach is to fully characterize the magnetic properties of rocks from intraplate shear zone and correlate these with geological processes related to the deformation. Key Points: Changes in the magnetic properties of fault rocks reveal the degree of tectonic reworking or structural position within the shear zoneAnisotropy of remanence experiments unravel distinct deformation stages or the heterogeneous response to the shearing by different grainsSystematic studies of exhumed analogs allow to constrain the magnetic properties in terms of localized versus distributed deformation [ABSTRACT FROM AUTHOR]

The bulk composition of overthickened Tibetan deep crust has been generally believed to be mafic granulite with eclogite at the lowermost crust. However, a granulitic/eclogitic deep crust is in contradiction to geological and geophysical observations in southern Tibet. Here we present petrofabrics and seismic properties of amphibolites from exhumed crustal part of the Indian plate in the eastern Himalayan syntaxis. Our results show strong fabrics of amphibole, nearly random fabrics of plagioclase and strong seismic anisotropies of amphibolites (AVp = 5.6–12.0% and Max. AVs = 5.1–7.7%). Comparing to a deep crust composed of nearly isotropic mafic granulite and weakly anisotropic eclogite, a thick amphibolitic layer in the middle‐lower crust would better account for the strong shear wave splitting (0.2–0.5 s in delay times or 4–15% in S wave anisotropy), the suture boundary parallel faster shear wave polarization, and the widespread postcollisional adakite‐like potassic rocks in southern Tibet. Plain Language Summary: We study the petrofabrics and seismic anisotropies of exposed lower crust of the subducting Indian plate. Our results show that a thick layer of amphibolites in the middle‐lower crust would agree better with the geological and geophysical observations than a deep crust entirely made of granulite and eclogite underneath southern Tibet. Key Points: Himalayan amphibolites are characterized by strong fabrics of amphibole and nearly random fabrics of plagioclaseHimalayan amphibolites show strong whole‐rock P wave and S wave seismic anisotropies mostly resulting from their amphibole componentsA thick amphibolite layer can account for the strong S wave splitting and the suture boundary parallel Vs1 polarization in southern Tibet [ABSTRACT FROM AUTHOR]

A geological evolution model of the Cuban archipelago is proposed with the objective of explaining the main geotectonic contexts and ages in which the main regional faults capable of generating earthquakes at present were originated, considering that this phenomenon does not seem to be fully solved in the different geological models consulted. The work was based on the assessment of the petrotectonic associations of the Cuban archipelago, identified based on the stratigraphic characteristics of the lithostratigraphic and lithodemic units described in the local and regional geological surveys, reflected in the geological maps and regulated in the Cuban Stratigraphic Lexicon of the 2013; as well as in its correspondence with the geotectonic contexts, petrotectonic associations, stages and stages established in the Wilson cycle. [ABSTRACT FROM AUTHOR]

To understand the relationships between eclogite‐facies mineral assemblages, deformation microstructures, and the seismic properties of subducting oceanic crust, eclogites from the Yuka terrane, North Qaidam ultrahigh‐pressure metamorphic belt, NW China, were studied. Observations of mineral textures, deformation microstructures, and petrofabrics in the eclogites indicate that garnet, omphacite, and phengite were deformed by intracrystalline deformation (i.e., dislocation creep) during prograde metamorphism. In contrast, amphibole, which was formed by the topotactic replacement of omphacite at fluid‐present conditions, is considered to have been deformed by diffusional flow (dissolution‐precipitation creep) during amphibolite‐facies retrogression associated with exhumation. Based on the petrofabrics in the samples, the seismic properties of the eclogites were calculated depending on eclogite‐facies mineral assemblages such as garnet + omphacite, garnet + omphacite + phengite, garnet + omphacite + phengite + lawsonite, garnet + omphacite + phengite + amphibole, and garnet + omphacite + amphibole. We found that the seismic signatures of each of the eclogite‐facies mineral assemblages were different. In particular, phengite‐bearing eclogites (the garnet + omphacite + phengite/garnet + omphacite + phengite + amphibole assemblages), depending on phengite content, produced the strongest seismic anisotropy (AVp and AVs), with a strong polarization anisotropy, that was at least three times higher than bimineralic (phengite‐absent) eclogites (garnet + omphacite assemblage). Our results indicate that phengite, as a stable phase at high‐pressure and high‐temperature conditions, can play an important role in the creation of trench‐parallel seismic anisotropy in the eclogite‐facies mineral assemblages found in subduction zones. Key Points: Seismic signatures are distinct for different eclogite‐facies mineral assemblagesPhengite‐bearing eclogite produces the strongest seismic anisotropy among different eclogite‐facies mineral assemblagesPhengite in eclogite‐facies mineral assemblages can play an important role in the creation of seismic anisotropy in subduction zones [ABSTRACT FROM AUTHOR]

Northwest Africa (NWA) 6112, Miller Range (MIL) 090206 (plus its pairs: MIL 090340 and MIL 090405), and Divnoe are olivine‐rich ungrouped achondrites. We investigated and compared their petrography, mineralogy, and olivine fabrics. We additionally measured the oxygen isotopic compositions of NWA 6112. They show similar petrography, mineralogy, and oxygen isotopic compositions and we concluded that these five meteorites are brachinite clan meteorites. We found that NWA 6112 and Divnoe had a c axis concentration pattern of olivine fabrics using electron backscattered diffraction (EBSD). NWA 6112 and Divnoe are suggested to have been exposed to magmatic melt flows during their crystallization on their parent body. On the other hand, the three MIL meteorites have b axis concentration patterns of olivine fabrics. This indicates that the three MIL meteorites may be cumulates where compaction of olivine grains was dominant. Alternatively, they formed as residues and were exposed to olivine compaction. The presence of two different olivine fabric patterns implies that the parent body(s) of brachinite clan meteorites experienced diverse igneous processes. [ABSTRACT FROM AUTHOR]

The WNW-ESE-striking Sinnyeong Fault, the most conspicuous fault of the Gaeum Fault System in the Cretaceous Gyeongsang Basin of Korea, provides an opportunity to understand the architectures and evolution of an intracontinental transpressional fault zone. We focus on the structural characteristics of the Sinnyeong Fault based on detailed field observations and magnetic fabric analysis. Its main movement is interpreted as sinistral slip with a small reverse component, although it could also have been active before the main movement. The deformation zone is asymmetric about the fault core. Sedimentary strata of the southern deformation zone are more extensively folded and deformed than those of the northern part, and the southern zone is much wider than the northern zone. NW-SE-trending en-echelon folds are limited to the southern periphery of the fault zone, where it is narrow, and underwent rotation toward the fault surface. These contractional deformations along the entire length of the fault are interpreted to have formed approximately coevally with the sinistral faulting. Newly observed WNW-ESE-striking mappable faults show a similar structural feature. Our results suggest that the damage asymmetry resulted from the eastward transport direction and relative uplift of south blocks of the faults under NE-SW compressive stress, which oriented at high angle (60-70°) to pre-existing strike of the faults. During progressive deformation, continuing slip accumulation along vertically tilted and fault-parallel sedimentary strata located directly south of the fault cores was responsible for the larger motions of the southern blocks of the faults rather than the relatively fixed northern blocks. We highlight that the sinistral reactivation of the Sinnyeong Fault formed a continuous, narrow transpressional zone during its long-term evolution. [ABSTRACT FROM AUTHOR]

Abstract Understanding of the microstructural evolution and equilibrium grain size development during steady state tertiary flow is essential in order to improve our knowledge of ice and rock deformation. This contribution presents results from in situ transmitted light deformation experiments of natural glacier ice, with the development of the microstructure in a tertiary flow regime. We conducted one relative slower (1 × 10 − 6 1/s) and two relative faster-strain rate (2 × 10 − 6 1/s) pure shear experiments at −10 °C, up to a shortening of ∼57%. Microstructure development was followed by time-lapse observations, and two new microstructure-based indicators, the 'seeding rate' and the 'microstructure activity', were introduced to evaluate whether a steady-state was reached. These indicate that a steady state was only reached in the two faster strain rate experiments. In contrast, during a slow deformation there is insufficient seeding of new grains to enable continuous recovery, and there is a bimodal grain size distribution. These results are explained by stress concentrations within grains. Particularly where basal planes are in unfavourable orientations for basal slip (hard glide orientation) coinciding with the development of a bimodal grain size distribution. In the case of bimodal grain size distributions the use of a stabilised mean grain size as a stress piezometer as a criterion for steady state should be handled with caution. Highlights • Mean grain size is not a reliable indicator for steady state. • 'Seeding rate' and 'microstructure activity' introduced as steady state indicators. • Concentration of stress on 'hard' grains can impede steady state in slow strain rate. [ABSTRACT FROM AUTHOR]

Abstract A fabric study of forsterite marble and calc-silicate rock paragenetic minerals is presented for samples collected in the Almadén de la Plata massif of SW Spain, that experienced Variscan low-pressure metamorphism related to the tectonic evolution of the suture between the Ossa-Morena and South-Portuguese zones of the Iberian Massif. Two tectonically stacked metamorphic units contain marble, metacarbonate and variably impure dolomitic rocks that record contrasting thermal conditions of the upper greenschist (structuraly upper unit) and the upper amphibolite/granulite facies (structuraly lower unit). Different reactional paths lead to formation of forsterite marbles in both units. Dolomite and calcite petrofabrics disclose their contrasting rheological behaviour during syn-metamorphic ductile deformation under temperatures between 500 and 700 °C. Dolomite formed (harder) porphyroclast systems and boudinaged bands, whereas weaker calcite underwent dynamic recrystallization. In both cases deformation was facilitated by activation of various intracrystalline slip systems, complemented by other deformation mechanisms. The fabrics of other paragenetic metamorphic minerals also denote crystal plasticity and exhibit close geometrical relationships with respect to the macroscopic foliation and mineral/stretching lineation, including a systematic asymmetry suggestive of non-coaxial deformation components. Foliations and lineations are interpreted as solid-state flow planes and directions bearing a kinematic significance. In particular, regional sinistral shear at mid-deep crustal realms coeval with low-pressure metamorphism explains the imbrication of metamorphic units and their exhumation, concomitant with the overall wrench tectonic framework ruling the tectonic evolution of the Ossa-Morena/South-Portuguese suture between the late Devonian (∼360 Ma) and the latest Carboniferous (∼300 Ma). Graphical abstract Image 1 Highlights • Variscan low-P/high T metamorphism coeval with ductile deformations. • Petrofabric and chemistry of carbonate rock paragenetic minerals constrain metamorphism. • Petrofabrics confer a kinematic significance to regional low-P/high-T foliations and lineations. • Contrasting thermal conditions in tectonically yuxtaposed units is related to wrench tectonics. [ABSTRACT FROM AUTHOR]

Abstract This work aims to characterize the Gavarnie thrust, one of the large-scale thrusts that define the Alpine structure of the west-central sector of the Pyrenees. A detailed comparison of structural analysis and magnetic fabrics is carried out for the Paleozoic phyllonites of the Gavarnie thrust, in order to decipher strain distribution and transport direction. The AMS at room (RT-AMS) and low (LT-AMS) temperature and the AIRM can be correlated with the structural patterns: k min axes are mainly parallel to the pole of the S, C or C′ planes and k max axes are parallel to the transport direction and related to ductile S-C structures. Furthermore, the Pj-T changes across the shear zone characterize strain variations: larger Pj and T are found in the basal, most deformed part of the shear zone, and lower values are found where the interaction between Alpine and Variscan-related petrofabrics is stronger. We also interpret the reactivation of Variscan inherited fabrics within the Alpine shear zone. In spite of the heterogeneous strain, markers indicate a common, top-to-the-South (N190E) Alpine transport direction, which contrasts with the strong obliquity of the genetically-related structures developed in the Southern Mesozoic sedimentary cover. In this sense, our data suggest a complete decoupling between basement and cover units during the Alpine compression. Highlights • AMS applied to study large shear zones at the brittle-ductile transition. • Changes in AMS ellipsoid related to different strain and deformational conditions. • Shear-reactivation of inherited petrofabrics in shear zones and its correlation with AMS. • Contribution to Cenozoic deformation in Pyrenees (Gavarnie Thrust, Axial zone). • The constant SSW transport direction suggests no vertical rotation for the Gavarnie Unit. [ABSTRACT FROM AUTHOR]

Abstract Boriskino is a little studied CM2 chondrite composed of millimeter-sized clasts of different lithologies and degrees of alteration. Boriskino thus offers a good opportunity to better understand the preaccretionary alteration history and collisional evolution that took place on the CM parent body. The least altered lithology displays 16O-poor Type 1a calcite and aragonite grains (δ18O ≈ 30–37‰, δ17O ≈ 15–18‰ and Δ17O ≈ −2 to 0‰, SMOW) that precipitated early, before the establishment of the petrofabric, from a fluid whose isotopic composition was established by isotopic exchange between a 16O-poor water and 16O-rich anhydrous silicates. In contrast, the more altered lithologies exhibit 16O-rich Type 2a and veins of calcite (δ18O ≈ 17–23‰, δ17O ≈ 6–9‰ and Δ17O ≈ −4 to −1‰, SMOW) that precipitated after establishment of the deformation, from transported 16O-rich fluid in preexisting fractures. From our petrographic and X-ray tomographic results, we propose that the more altered lithologies of Boriskino were subjected to high intensity impact(s) (10–30 GPa) that produced a petrofabric, fractures and chondrule flattening. Taking all our results together, we propose a scenario for the deformation and alteration history of Boriskino, in which the petrographic and isotopic differences between the lithologies are explained by their separate locations into a single CM parent body. Based on the δ13C-δ18O values of the Boriskino Type 2a calcite (δ13C ≈ 30–71‰, PDB), we propose an alternative δ13C-δ18O model where the precipitation of Type 2a calcite can occurred in an open system environment with the escape of 13C-depleted CH 4 produced from the reduction of C-bearing species by H 2 released during serpentinization or kamacite corrosion. Assuming a mean precipitation temperature of 110 °C, the observed δ13C variability in T2a calcite can be reproduced by the escape of ≈15–50% of dissolved carbon into CH 4 by Rayleigh distillation. [ABSTRACT FROM AUTHOR]

Abstract We investigated the evolution of the structure, physical properties and fluid flow properties across a fault zone within the Toarcian shale formation from the Tournemire Underground Research Laboratory (France). With this purpose, an integrated approach was used based on the analysis of petrofabric (anisotropy of magnetic susceptibility, AMS, and of p-wave velocity, APV) and the mineralogy of two cores intercepting the F2 fault, a strike-slip fault with a small vertical offset. The fracture patterns indicated that the fault registered a multiphase tectonic evolution. Two strike-slip regimes, with approximate NE-SW and NW-SE compression, and a normal regime with a WNW-ESE direction of extension were identified. Most of the N-S fault planes collected in TF1 core, have a shallow dip with values between 5° to 45°. We further evidenced a close relationship between the fault architecture and petrophysical properties. A preferential NW-SE orientation of the K1 axes was observed that is in agreement with the extensional direction of the dextral movement of the fault. Within the fault core, an important decrease in anisotropy was observed and indicates clay platelets rotations related to tectonic deformation. A weaker anisotropic change was observed in ASM1. This difference may be related to the local variability of the fault zone and suggests the need to study the characteristics of a fault zone both across its different architectural zones and along the main fracture plan. Finally, we identified evidence of minerals alteration related to fault reactivation and fluid circulation. Fluid circulation enabled the transformation of siderite in magnetite, a neo-formation of kaolinite and a precipitation of calcite were at vicinity of the damage zone/fault core boundary. In TF1, while the major mineralogical changes occur in the damage zone. In ASM1, a higher illite-smectite mixed layers and calcite content was observed in the eastern side of the fault. Highlights • The F2 fault underwent a polyphased tectonic evolution. • Fracture patterns and petrophysical properties are influenced by tectonics. • Clay platelet rotation is observed near the fracture. • There are evidences of mineralogical changes related to fluid circulation. [ABSTRACT FROM AUTHOR]

The present work aims to characterize the reservoir properties of the upper Khuff Formation using integrated core plugs, petro-fabrics and Mercury injection analyses. A thirty four rock samples are picked up from the exposure of the upper Khuff Formation (Khuff A Member) at Al-Qassim province. These samples are subjected to a verity of laboratory measurements including core plugs, thin sections and mercury injection as matched with well log and crude oil analyses. Good porosity and permeability ranges (4–18% and 5–20 mD) are indicated, especially at the lower part with a uni-modal pore size distribution. The lithology is mainly dolomitic with minor limestone. Some fractures, cemented pores and dissolution process are indicated at the middle and upper parts of the section, respectively. Autopore-based mercury injection is performed to determine the volume of intrusion, touristy, pore size distribution and diameter. Total intrusion volumes of 0.352, 0.137 and 0.036 ml, threshold pressures of 127.44, 146.04 and 216.00 psi and tortuosities of 40.01, 75.19 and 60.26 are indicated for the analyzed samples, respectively. The results of the logging analyses are matched with the laboratory ones. Good hydrocarbons content is recognized in the middle part of the section. The analysis of crude oil sample indicates medium oil with high carbon content of 81.29 wt% and average specific gravity of 0.886 gm/cc. In conclusion, this integrated study indicates that the lower part of the Khuff A Member attains the best reservoir properties among the studied section. [ABSTRACT FROM AUTHOR]

Abstract: Shatter cones are diagnostic for the recognition of meteorite impact craters. They are unambiguously identifiable in the field and the only macroscopic shock deformation feature. However, the physical boundary conditions and exact formation mechanism(s) are still a subject of debate. Melt films found on shatter cone surfaces may allow the constraint of pressure–temperature conditions during or immediately after their formation. Within the framework of the MEMIN research group, we recovered 24 shatter cone fragments from the ejecta of hypervelocity impact experiments. Here, we focus on silicate melt films (now quenched to glass) found on shatter cone surfaces formed in experiments with 20–80 cm sized sandstone targets, impacted by aluminum and iron meteorite projectiles of 5 and 12 mm diameter at velocities of 7.0 and 4.6 km s−1, respectively. The recovered shatter cone fragments vary in size from 1.2 to 9.3 mm. They show slightly curved, striated surfaces, and conical geometries with apical angles of 36°–52°. The fragments were recovered from experiments with peak pressures ranging from 46 to 86 GPa, and emanated from a zone within 0.38 crater radii. Based on iSale modeling and petrographic investigations, the shatter coned material experienced low bulk shock pressures of 0.5–5 GPa, whereas deformation shows a steep increase toward the shatter cone surface leading to localized melting of the rock, resulting in both vesicular as well as polished melt textures visible under the SEM. Subjacent to the melt films are zones of fragmentation and brittle shear, indicating movement away from the shatter cone apex of the rock that surrounds the cone. Smearing and extension of the melt film indicates subsequent movement in opposite direction to the comminuted and brecciated shear zone. We believe the documented shear textures and the adjacent smooth melt films can be related to frictional melting, whereas the overlying highly vesiculated melt layer could indicate rapid pressure release. From the observation of melting and mixing of quartz, phyllosilicates, and rutile in this overlying texture, we infer high, but very localized postshock temperatures exceeding 2000 °C. The melted upper part of the shatter cone surface cross‐cuts the fragmented lower section, and is accompanied by PDFs developed in quartz parallel to the {11 2 ¯2} plane. Based on the overprinting textures and documented shock effects, we hypothesize shatter cones start to form during shock loading and remain an active fracture surface until pressure release during unloading and infer that shatter cone surfaces are mixed mode I/II fracture surfaces. [ABSTRACT FROM AUTHOR]

Anisotropy of magnetic susceptibility (AMS) analysis is used as a petrofabric indicator for a set of four identical-setup sandbox models that were shortened by different amounts and simulate contraction in a fold-and-thrust belt. During model shortening, a progressive reorientation of the initial magnetic fabric occurs due to horizontal compaction of the sand layers. At the early stages of shortening, magnetic lineation (k1 axis) rotates parallel to the model backstop with subhorizontal orientation, whereas the minimum susceptibility (k3 axis) is subvertical, which indicates a partial tectonic overprint of the initial fabric. With further shortening, the k3 axis rotates to subhorizontal orientation, parallel to shortening direction, marking the development of a dominant tectonic magnetic fabric. A near-linear transition in magnetic fabric is observed from the initial bedding to tectonic fabric in all four models, which reflects a progressive transition in deformation from foreland toward hinterland. Model results confirm a long-held hypothesis where the AMS pattern and degree of anisotropy have been suggested to reflect the amount of layer-parallel shortening, based on field observations in many mountain belts. Results furthermore indicate that grain rotation may play a significant role in low-grade compressive tectonic regimes. The combination of analogue models with AMS enables the possibility to predict magnetic fabrics in different tectonic settings and to develop quantitative links between AMS and strain. [ABSTRACT FROM AUTHOR]

Abstract: The approximately spherical shapes of chondrules has long been attributed to surface tension acting on ~1 mm melt droplets that formed and cooled in the microgravity field of the solar nebula. However, chondrule shapes commonly depart significantly from spherical. In this study, 109 chondrules in a sample of CR2 chondrite NWA 801 were imaged by X‐ray computed tomography and best‐fitted to ellipsoids. The analysis confirms that many chondrules are indeed not spherical, and also that the chondrules’ collective shape fabric records a definite 13% compaction in the host meteorite. Dehydration of phyllosilicates within chondrules may account for that strain. However, retro‐deforming all chondrules shows that a large majority were already far from spherical prior to accretion. Possible models for these initial shapes include prior deformation of individual chondrules in earlier hosts, and, as suggested by previous authors, rotation of chondrules as they were solidifying, and/or “streaming” of molten chondrules by their differential velocities with their gaseous hosts after melting. More in situ 3‐D work such as this study on a variety of unequilibrated chondrites, combined with detailed structural petrography, should help further constrain these models and refine our understanding of chondrite formation. [ABSTRACT FROM AUTHOR]

Magnetic fabric allows to unravel the petrofabrics of sedimentary rocks and to assess their deformational history. The use of this technique, in addition to classical structural field observations in the limbs of seven asymmetric folds in the Pyrenees, helps to determine the differences of internal deformation as well as the folding kinematics. Three folds developed during the Variscan Orogeny in Ordovician and Devonian rocks, and four folds developed during the Pyrenean Orogeny in Eocene rocks, are studied. Folds show a variety of structural locations, in different thrust sheets of the Southern Central Pyrenees, different cleavage development, age, geometry and lithology. Sampling follows an equivalent lithological layer in the two limbs, except for one case, of the selected folds. Results show a modified tectonic magnetic fabric in most sites with the magnetic lineation on the tectonic foliation plane. A larger scattering of the magnetic lineation (maximum magnetic anisotropy axis) and a higher intensity of the preferred orientation of minerals (eccentricity of the anisotropy of magnetic susceptibility - AMS ellipsoid) is better observed in the overturned (short) limb of the asymmetric Variscan folds than in the normal (long) limb. On the other hand, the shape parameter in Alpine folds is generally larger in the overturned (short) limb then in the normal (long) one. A good clustering of the minimum magnetic anisotropy axes is observed in all limbs. The combination of the AMS data with the structural data helps to understand and better constrain the deformation degree in these asymmetric folds and to unravel the deformational history. [ABSTRACT FROM AUTHOR]

We used Itrax XRF, magnetic susceptibility, grain size, and micro-CT scanning to provide a facies classification for a Late Holocene sediment sequence from Lake Chappa'ai in the Southern Alps, New Zealand. The record contained multiple diamictic layers and our objective was to determine the environmental significance of these deposits. Clast fabric analysis indicated that the diamicts comprise dropstones transported to the centre of the lake by ice rafting. Diamicts belonging to Facies 1 represent rock falls onto lake ice triggered by earthquakes that produced MMI (Modified Mercalli Intensity) > 8 shaking in the catchment. MMI >8 earthquakes may need to occur when the lake has ice cover to produce Facies 1 diamicts. MMI >8 earthquakes in the ice free season or MMI 7–8 earthquakes may also result in an increased flux of large (>1 mm) clasts to the centre of the lake, but may not produce a Facies 1 diamict. More work is required to establish the role of climate related processes on the formation of non-Facies 1 diamicts in Lake Chappa'ai. Climate change may directly lead to diamict formation by changing lake ice cover and facilitating transport of large clasts by anchor ice, or increasing the likelihood of rain on snow events in the spring. Changing ice cover conditions will also affect how mountain lakes record past earthquake events. Lakes that are ice free will not produce earthquake diamicts and lakes that have perennial ice cover may produce a single diamict representing multiple earthquakes if the lake becomes ice free. A reduction in the duration of winter ice cover will also decrease the probability of capturing primary rockfall deposits from earthquakes. Additional data, such as a diatom or chironomid record from Lake Chappa'ai may help to resolve the contribution of climate processes to diamict formation. We should consider the Lake Chappa'ai record as an indicator of minimum earthquake activity until we can disentangle the effects of climate change on non-Facies 1 diamict formation. This study highlights the multiple mechanisms that can lead to diamict formation in mountain lake sediments. These processes should always be considered before attributing the presence of diamict deposits to ice-rafted debris in a pro-glacial lake. This is particularly true in seismically active settings where earthquake triggered rockfalls may lead to diamict formation. [ABSTRACT FROM AUTHOR]

Abstract: Detailed petrography and modal analysis of 35 sandstone thin sections was carried out to determine petrotectonic setting of the provenance of the Lower Siwalik molasse of southeastern Kumaun Himalaya. The sandstones are fine‐ to coarse‐grained (0.14–0.63 mm), poorly‐ to moderately‐sorted and comprise lithic arenites, sublithic arenites and lithic greywackes. The sandstones invariably belong to the quartzolithic QtFL (Qt, total quartz; F, feldspar; L, lithic grains) and QmFLt (Qm, monocrystalline quartz; Lt, lithic grains plus polycrystalline quartz) petrofacies, and indicate their derivation from a quartzose‐ and transitional‐recycled orogen provenance under sub‐humid climatic conditions. The framework composition of the sandstones comprises abundant monocrystalline and polycrystalline quartz and low‐ to high‐grade metamorphic rock fragments, along with subordinate feldspar, characterized by low ratios of plagioclase to total feldspar, and accessory minerals. The framework composition and petrofacies characters of these texturally submature sandstones suggest their derivation mainly from the nearby located Great Himalaya terrane and subordinately from the Tethys and Lesser Himalayan terranes. A comparison of the data presented here with the previous similar data from Lower Siwalik of northwestern Pakistan, northwestern India, south‐central Kumaun, western Nepal and southeastern Nepal reveals that like the Lower Siwalik rivers in other sections, the Lower Siwalik rivers of the southeastern Kumaun too drained large parts of the Great Himalayan terrane and some parts of the Tethys and Lesser Himalayan terranes. [ABSTRACT FROM AUTHOR]

In 2010, fine regolith particles on asteroid Itokawa were recovered by the Hayabusa mission. The three-dimensional microstructure of 48 Itokawa particles smaller than 120 µm was examined in previous studies. The shape distribution of Itokawa particles is distributed around the mean values of the axial ratio 2:√2:1, which is similar to laboratory impact fragments larger than several mm created in catastrophic disruptions. Thus, the Itokawa particles are considered to be impact fragments on the asteroid's surface. However, there have never been any laboratory impact experiments investigating the shapes of fine fragments smaller than 120 µm, and little is known about the relation between the shapes of fine fragments and the petrographic textures within those fragments. In this study, in order to investigate the relation between the petrographic textures and the shapes of fine fragments by impacts, the shapes of 2163 fine fragments smaller than 120 µm are examined by synchrotron radiation-based microtomography at SPring-8. Most samples are fine fragments from basalt targets, obtained in previous laboratory impact experiments by Michikami et al. (2016). Moreover, two impacts into L5 chondrite targets were carried out and the shapes of their fine fragments are examined for comparison. The results show that the shape distributions of fine fragments in basalt targets are similar regardless of impact energy per target mass (in contract to the shape distribution of relatively large fragments, which are affected by impact energy), and are similar to those in L5 chondrite targets and Itokawa regolith particles. The physical process producing these fine fragments would be due to multiple rarefaction waves in the target. Besides, the petrographic textures do not significantly affect the shapes of fine fragments in our experiments. On the other hand, according to Molaro et al. (2015), the shapes of the fragments produced by thermal fatigue by the day-night temperature cycles on the asteroid surface are influenced by the petrographic textures. Therefore, we conclude that the Itokawa particles are not the products of thermal fatigue but impact fragments on the asteroid surface. [ABSTRACT FROM AUTHOR]

This paper investigates an unsupervised approach for fabric defect detection using un-decimated wavelet decomposition and simple statistical models. A novel data fusion scheme is proposed to merge the information from the different channels into a unique feature map in which potential defective regions will be highlighted distinctly. The distribution of the pixel values corresponding to the defect-free background texture in the feature map is modeled as per the Gumbel distribution model whose parameters are estimated by partitioning the feature map into a set of small patches. By calculating the log-likelihood value of each patch, a log-likelihood map (LLM) can be conveniently created, which provides a good cluster representation of the non-defective regions. A simple thresholding procedure then follows to discriminate between defective regions and homogeneous background in the LLM. The performance of the method has been extensively evaluated using a variety of real fabric samples, and the effectiveness of the proposed scheme has been verified by experimental results in comparison with other methods. [ABSTRACT FROM AUTHOR]

Abstract: Deformation partitioning is identified as the fingerprint of late Palaeozoic continental subduction that affected various lithologies whose field relationship, thermobarometric and petrofabric features are closely related. Different modes of deformation partitioning can be identified within medium temperature, high‐P eclogite lenses, between them and the host gneisses, and within the latter. Development of foliations and lineations with a coherent attitude in all these rocks and their related structural petrology demonstrate that eclogite enclosures and their country rocks underwent a common, pervasive deformational event. The published P–T stability fields of the eclogite phases that define the microscopic fabric are used to define the metamorphic conditions prevailing during the deformation event and relate it to the subduction process. The mineral equilibria of the gneisses (ortho‐ and paragneisses) fail to record the full range of those P–T conditions, but the field relationships show that eclogites were originally basic dykes emplaced in acid igneous rocks and demonstrate that the eclogites and gneisses shared a common tectonometamorphic evolution. Deformation partitioning within the latter occurred at variable scales and involved (1) meso macroscale preservation of virtually undeformed metagranite bodies, surrounded by (2) pervasively foliated and lineated gneisses, and (3) the simultaneous microscale operation in the latter of ductile and brittle–ductile mechanisms at conditions above 500°C and below 1.5 GPa. A subduction channel tectonic setting is proposed to explain the subduction of upper to mid‐crustal igneous rocks and exhumation subsequent to high‐P metamorphism. Its currently accessible dimensions, and its organization into several lithotectonic units mapped as nappes support tectonic amalgamation of units several km3 in volume. Maximum burial in the subduction channel likely reached depths shallower than the lithostatic pressure implied by geobarometric calculations, possibly conditioned by a sudden pressure drop during the initial retrogression stages accompanying exhumation. [ABSTRACT FROM AUTHOR]

We present a detailed geologic study of the Thebes Formation at Gebel Gurnah in its locus typicus on the West Bank (opposite Luxor) of the Nile River in the Upper Nile Valley, Egypt. This is the first detailed measurement and lithologic description of the ∼340 m thick (predominantly) carbonate section. The Thebes Formation is divided into thirteen major lithic units (A to M). We interpret data on the lithologic succession and variations, whole rock/clay mineralogy, and macro/micropaleontology in terms of deposition on a shallow carbonate platform episodically influenced by continental runoff, and describe six depositional sequences that we place in the global framework of Lower Eocene (Ypresian) sequence stratigraphy. We note however significant incompatibilities between the Thebes depositional sequences and the global sequences. We emend the definition of the Thebes Formation by defining its top as corresponding to level 326 m at the top of Nodular Limestone ‘L’ (NLL), and assigning the overlying beds to the Minia Limestone Formation. New biostratigraphic data and revision of previous studies establish the direct assignment of the Thebes Formation to planktonic foraminiferal Zones E4/P6b (upper part), E5/P7 and (indirectly) Zone E6/P8, and (probably, indirectly) Zone E7a/”P9”, and to calcareous nannofossil Zone NP12 and lower Zone NP13 of the Lower Eocene (Ypresian) and provide a temporal framework spanning ∼ 2.8 Myr from <52.45 to ∼49.6 Ma for the deposition of the Thebes Formation prior to the prominent sea level fall (∼49.6 Ma) towards the end of the Early Eocene. Dominantly carbonate deposition, with a strongly reduced detrital influx, occurred on a very wide shelf (probably) at least ∼ 100 km from the coastline. The thick sedimentary succession and the marked vertical lithologic variations are interpreted as resulting from sea level fluctuations imprinted on a long-term decrease in sea-level associated with rapid subsidence reflecting tectonic relaxation after the major Late Paleocene tectonic reorganization of the Syrian Arc. [ABSTRACT FROM AUTHOR]

We applied X-ray computed microtomography (μ-CT) in combination with anisotropy of magnetic susceptibility (AMS) analysis to study metamorphic rock fabrics in an oriented drill core sample of pyrite-pyrrhotite-quartz-mica schist. The sample is extracted from the Paleoproterozoic Martimo metasedimentary belt of northern Finland. The μ-CT resolves the spatial distribution, shape and orientation of 25,920 pyrrhotite and 153 pyrite grains localized in mm-thick metapelitic laminae. Together with microstructural analysis, the μ-CT allows us to interpret the prolate symmetry of the AMS ellipsoid and its relationship to the deformation history. AMS of the sample is controlled by pyrrhotite porphyroblasts that grew syntectonically during D1 in subhorizontal microlithons. The short and intermediate axes (K3 and K2) of the AMS ellipsoid interchanged positions during a subsequent deformation (D2) that intensely crenulated S1 and deformed pyrrhotite, while the long axes (K1) maintained a constant position parallel to the maximum stretching direction. However, it is likely that all the three AMS axes switched, similar to the three principal axes of the shape ellipsoid of pyrite porphyroblasts from D1 to D2. The superposition of D1 and D2 produced a type-2 fold interference pattern. [ABSTRACT FROM AUTHOR]

New detailed (micro-)structural investigations, quartz petrofabric analyses and geological/structural mapping in southeast Syros (Cycladic massif, Aegean region) allow us to place new constraints on the tectonic evolution of the Uppermost unit, which occupies the immediate hanging-wall of the crustal-scale Vari Detachment. We show that the Eocene ‒ Oligocene deformation history in the hanging-wall of this detachment is associated with SW-directed ductile shearing. This history includes an early distributed constrictional deformation expressed by transport-parallel upright folds, L-tectonites and cleft-girdles quartz c-axis fabrics that were formed at temperatures ∼ 500 °C. Ductile deformation progressively localized at the bottom of the Uppermost unit leading to the formation of a greenschist-facies mylonitic zone under plane strain conditions inferred from Type-I cross-girdles quartz c-axis fabrics. The ongoing mylonitization was also associated with temporally increasing pure shear component of deformation coupled with cooling from ∼ 500 °C to ∼ 400 °C. We suggest that the Vari Detachment represents a passive normal-sense roof fault resulted from the NE-directed ductile extrusion of the Blueschist unit (footwall) at middle Eocene ‒ Oligocene times. In the middle Miocene, the activation of the brittle SSW-directed Late Vari Detachment enhanced the brittle exhumation of both the Blueschist unit and the Vari Detachment. [ABSTRACT FROM AUTHOR]

The orientations of dehydration cracks and fracture networks in fine-grained, unmelted micrometeorites were analyzed using rose diagrams and entropy calculations. As cracks exploit pre-existing anisotropies, analysis of their orientation provides a mechanism with which to study the subtle petrofabrics preserved within fine-grained and amorphous materials. Both uniaxial and biaxial fabrics are discovered, often with a relatively wide spread in orientations (40°-60°). Brittle deformation cataclasis and rotated olivine grains are reported from a single micrometeorite. This paper provides the first evidence for impact-induced shock deformation in fine-grained micrometeorites. The presence of pervasive, low-grade shock features in CM chondrites and CM-like dust, anomalously low-density measurements for C-type asteroids, and impact experiments which suggest CM chondrites are highly prone to disruption all imply that CM parent bodies are unlikely to have remained intact and instead exist as a collection of loosely aggregated rubble-pile asteroids, composed of primitive shocked clasts. [ABSTRACT FROM AUTHOR]

In Great Nicobar island ophiolite is restricted to the eastern coast of the island and occur as small isolated out crops in the terrain of Oligocene sediments. The ophiolitic rocks are represented by pillowed basalt, massive andesite and pyroclastic andesite. These volcanics represent dismembered members of the upper part of the ophiolite. Basalt is porphyritic in nature where phenocrysts of augite and plagioclase laths are set in a fine grained glassy to chloritic matrix. Andesites consists of phenocrysts of augite, altered feldspar and minor quartz which are set in ground mass of epidote-chlorite glass. Trace element and REE pattern suggests more fertile mantle source for andesite than that of basalt. Trace element characteristics indicate that the andesites and basalts were possibly derived from the same melt where andesite represents the more fractionated product. In Andaman Islands dismembered ophiolite with complete ophiolite stratigraphy are found only within the Eocene sediments. But the field disposition suggests that in Great Nicobar emplacement of the ophiolite continued even after the Oligocene sedimentation. The characters of the ophiolitic rocks in Great Nicobar island are similar to that of the Sunda outer arc ridge. [ABSTRACT FROM AUTHOR]

Durability and suitability of concrete aggregates are influenced by mineralogical composition. This paper therefore discuses the mineralogical composition of Jhelum river aggregates and identifies the deleterious components responsible of ASR expansion, when used in normal weight concrete. Accelerated Mortar Bar Test (ASTM C-1260) and petrographic analysis were performed to determine the durability aspects of river aggregate. Aggregate Suitability was assessed by aggregate quality tests i.e. specific gravity & absorption, Loss Angeles abrasion, sulfate soundness, shape test, fineness modulus and sand equivalent. On obtaining satisfactory results of coarse aggregate tests, concrete mix designs for class-A, class-B, class-C and class-D were devised by absolute volume method (ACI- 211.1). Projected UCS (Unconfined Compressive Strength) considered 4000Psi for A-type, 3000Psi for B-type, 2000Psi for C-type and 1500Psi for D- type concrete at the at 28days. Results of 24 casted cylinders show that achieved average UCS at the age of 28 days is, 4921 Psi, 3773 Psi, 2780 Psi and 2432Psi for A, B, C and D-type concrete respectively. Jhelum River Aggregate is found mechanically fit and suitable for normal weight concrete. There are about 40% samples which deviate from the suitability standard of Accelerated Mortar Bar Test. Mineralogical studies of Jhelum river aggregate revealed that most of the aggregate components (Sandstone, Quartz Arenite) are suitable for construction but some of these are highly susceptible to alkali silica reaction due to the presence of highly strained quartz. The studied river aggregate is economical while used with slag cement and additives. [ABSTRACT FROM AUTHOR]

The present study reports on elemental and Sr isotopic analyses of calcite and associated celestite infillings of various microtectonic features collected mostly in the Main Fault of the Opalinus Clay from Mont Terri rock laboratory. Based on a detailed microstructural description of veins, slickensides, scaly clay aggregates and gouges, the geochemical signatures of the infillings were compared to those of the leachates from undeformed Opalinus Clay, and to the calcite from veins crosscutting Hauptrogenstein, Passwang and Staffelegg Formations above and below the Opalinus Clay. Vein calcite and celestite from Main Fault yield identical Sr/Sr ratios that are also close to those recorded in the Opalinus Clay matrix inside the Main Fault, but different from those of the diffuse Opalinus Clay calcite outside the fault. These varied Sr/Sr ratios of the diffuse calcite evidence a lack of interaction among the associated connate waters and the flowing fluids characterized by a homogeneous Sr signature. The Sr/Sr homogeneity at 0.70774 ± 0.00001 (2σ) for the infillings of most microstructures in the Main Fault, as well as of veins from nearby limestone layer and sediments around the Opalinus Clay, claims for an 'infinite' homogeneous marine supply, whereas the gouge infillings apparently interacted with a fluid chemically more complex. According to the known regional paleogeographic evolution, two seawater supplies were inferred and documented in the Delémont Basin: either during the Priabonian (38-34 Ma ago) from western Bresse graben, and/or during the Rupelian (34-28 Ma ago) from northern Rhine Graben. The Rupelian seawater that yields a mean Sr/Sr signature significantly higher than those of the microstructural infillings seems not to be the appropriate source. Alternatively, Priabonian seawater yields a mean Sr/Sr ratio precisely matching that of the leachates from diffuse calcite of the Opalinus Clay inside the Main Fault, as well as that of its microstructures and the same features of the sediments above and below. To envision a Priabonian seawater supply, there is a need for its storage without a significant evolution in its Sr isotopic composition until the final deformation of the area. The paleo-hydrogeological context calls for a possible infiltration of the seawater into a limestone karst located above the Opalinus Clay that could have acted as the storage reservoir. The karstic nature of this reservoir also explains why the Sr/Sr of the fluids was not modified significantly until expulsion. An alternative storage could have been provided by the regional faulting system that developed during the contemporary regional rifting of the Rhine Graben. The fluid expulsion started along these extensional faults during the further Upper Eocene-Lower Oligocene rifting phase. Later, the thin-skinned deformation of the Jura Belt affected the Mont Terri region in the form of the Main Fault, probably between approximately 9 and 4 Ma on the basis of preliminary K-Ar ages of nanometer-sized authigenic illite crystals recovered from gouge samples. [ABSTRACT FROM AUTHOR]

Fabrics from Anisotropy of Magnetic Susceptibility (AMS) analyses and Shape Preferred Orientation (SPO) of plagioclase are compared with field structures (such as bridge structures, intrusive steps and magma lobes) formed during magma intrusion in Jurassic sills. This is to constrain magma flow directions in the sills of the Karoo Igneous Province along the KwaZulu-Natal North Coast and to show how accurately certain structures predict a magma flow sense, thus improving the understanding of the Karoo sub-volcanic dynamics. The AMS fabrics are derived from magnetite grains and are well constrained, however the SPO results are commonly steeply inclined, poorly constrained and differ to the AMS fabrics. Both techniques resulted in asymmetrical fabrics. Successful relationships were established between the AMS fabric and the long axes of the magma flow indicators, implying adequate magma flow prediction. However, where numerous sill segments merge, either in the form of magma lobes or bridge structures, the coalescence process creates a new fabric between the segments preserving late-stage magma migration between the merged segments, overprinting the initial magma flow direction. [ABSTRACT FROM AUTHOR]

Along the northern Ionian margin of Calabria, three Neogene basins comprise wedge-top depozones containing syntectonic deposits which cover the frontal part of the fold-thrust belt. One of the best exposed onshore allochthonous siliciclastic successions is represented by the Cariati Nappe, cropping out in the Cirò Basin. Field geological mapping and aerial interpretations were used to characterize the stratigraphy and tectonics of the area between the Arso Stream and Nicà River catchments (about 170 km2), including a Paleozoic metamorphic basement complex unconformably overlain by Upper Oligocene to Quaternary siliciclastic deposits and minor carbonates. This paper presents a 1:25,000 scale map of the Ionian study area, providing lithological and structural data towards reconstructing its tectono-sedimentary evolution. [ABSTRACT FROM PUBLISHER]

The article discusses the highlights of the Annual General Meeting (AGM)-2016 of the Geological Society of India at the Indian Institute of Technology (IIT) in Kharagpur, India during the last week of October. Highlights include a seminar on developments in geosciences, workshops on Mohr circle simplified and modern methods of fabric analysis in deformed rocks, and opening remarks by Vice President Shri S. V. Srikantia.

Bedrock mapping, structural analysis, documentation of kinematics and associated petrofabrics, and detailed zircon and monazite geochronology are the basis for a new interpretation of the post-Acadian tectonic evolution of southern New England. Early fabrics in the Central Maine Zone and eastern half of the Bronson Hill Zone are characterized by planar foliations, subhorizontal lineations, and dextral kinematic indicators. As transpression progressed, structures and fabrics reflected an increased component of shortening, marked by tightening of foliations, development of closed to isoclinal folds, localization of reverse high strain zones, steep dip-parallel lineations, and reverse top-to-east kinematic indicators. Syntectonic mineral assemblages show that cooling attended deformation, consistent with a component of vertical extrusion. In contrast, the western half of the Bronson Hill Zone is characterized by sinistral top-to-south deformation from Connecticut to New Hampshire, including two regional sinistral shear zones, and comprise the Western Bronson Hill Shear System. New zircon and monazite geochronology, along with previously published results, show that dextral transpression progressed continuously from ~350 Ma to ~295 Ma. Dextral transpression was initiated following ~360 Ma to ~355 Ma dioritic, tonalitic, and granitic magmatism. Sillimanite-grade reverse high strain zones developed by ~330Ma, while the presence of lower-grade fabrics, metamorphic zircon rims, and published hornblende cooling ages show deformation continued to at least ~295 Ma in the eastern Bronson Hill and Central Maine. Sinistral top-to-south deformation in the Western Bronson Hill Shear System preceded ~330 Ma to ~300 Ma staurolite grade metamorphism, and syntectonic monazite and an abundance of published data show that deformation continued to ~285 Ma. The conjugate shear zones were spatially and temporally linked, indicating that the dominant fabrics, structures, and mineral assemblages in bedrock exposures in this area of New England were driven by progressive dextral transpression and lateral escape in the Carboniferous, much younger than any previous tectonic reconstruction. This model can explain an assortment of enigmatic features in New England, including contrasting kinematics, differential exhumation of lithologies and lithotectonic zones, and the Pelham dome. These features are attributed to oblique convergence between Laurentian margin and Avalon/Meguma beginning in the Mississippian, rather than the Early to Middle Devonian Acadian orogeny as has long been proposed. The location between the New York promontory and the Quebec embayment could have provided the necessary geometry to focus deformation and lateral escape in New England, and shorten the orogen in this area by almost an order of magnitude. [ABSTRACT FROM AUTHOR]

Color matching of fabric blends is a key issue for the textile industry, mainly due to the rising need to create high-quality products for the fashion market. The process of mixing together differently colored fibers to match a desired color is usually performed by using some historical recipes, skillfully managed by company colorists. More often than desired, the first attempt in creating a blend is not satisfactory, thus requiring the experts to spend efforts in changing the recipe with a trial-and-error process. To confront this issue, a number of computer-based methods have been proposed in the last decades, roughly classified into theoretical and artificial neural network (ANN)-based approaches. Inspired by the above literature, the present paper provides a method for accurate estimation of spectrophotometric response of a textile blend composed of differently colored fibers made of different materials. In particular, the performance of the Kubelka-Munk (K-M) theory is enhanced by introducing an artificial intelligence approach to determine a more consistent value of the nonlinear function relationship between the blend and its components. Therefore, a hybrid K-M+ANN-based method capable of modeling the color mixing mechanism is devised to predict the reflectance values of a blend. [ABSTRACT FROM AUTHOR]

The morphology and chemical characteristics of mineral soils underlying modern peaty (histic) and shallow peat soils (or histosols) are analyzed in pedoecological conditions of Estonia. The underlying shallow peat mantle gley soils have been formed on different geological origin (glaciolacustrine, glacial, glaciofluvial, marine) parent materials. The peat mantle overlying gley soils has accumulated in the process of landscape paludification during the post glacial period. Using the Estonian Soil Classification (ESC), the peat layer thickness of peaty soils is 10–30 cm and of shallow peat soils, 30–100 cm. The studied peaty soils may be characterized as polygenetic soils. Depending on parent material properties (calcareousness, acidity, texture) and feeding water the peaty soils are divided into two types specified by ESC as peaty gley soils and peaty podzols, and by WRB as Histic Gleysols and Histic Podzols. The mineral soils underlying peat soils may be defined as paleosols. The development of such soils has proceeded according to the chronosequence: gley soils or protosols → peaty soils → fen soils → transitional bog soils → bog soils, whereas mineral paleosols may be found under fen, transitional bog and bog soils. The peat soils studied in this research work, classified by ESC as drained shallow transitional (mesotrophic) bog soils and by WRB as Drainic Dystric Ombric Hemic Fibric Histosols, are located on the edges of bog areas and are fed mostly by mesotrophic surface seepage water. In comparative analysis of three soil groups (peaty gley soils, peaty podzols and shallow peat soils) (i) their location on the landscape, the geological origin of their parent materials and morphology of the mineral layers are characterized; (ii) the vertical distribution of organic carbon and total nitrogen contents, and different characteristics of soil acidity are analyzed, and (iii) their catenal position or associated soils are characterized. In the case of peaty soils, the three types of mineral soil profiles (eluvial, eluvio-accumulative and accumulative) which underlie the peat cover were elucidated. Under thicker peat layers, i.e. under shallow peat soils, mostly humus accumulative profiles were found. In all analyzed sites, in the course of progressive paludification (among this peatification) the peaty soils have been formed from gley soils. The formation of the peaty soil stage was followed by the fen soil stage. Depending on the feeding water, some of these soils developed in the direction of bog soils, with an intermediary transitional bog stage. Artificial drainage is of great importance in the development of peat cover, which influences first the decomposition of top layer peat. [ABSTRACT FROM AUTHOR]

SVM and SAM classifiers for the lithological mapping using Hyperion data in parts of Gadag schist belt of western Dharwar craton, Karnataka, India were used. The main objective of the present study is to assess and compare the potential use of Hyperion data set for lithological mapping. Accuracy assessment of the derived thematic maps was based on the analysis of the confusion matrix statistics computed for each classification map. For consistency, the same set of validation points were used in evaluating the accuracy of the lithological thematic maps produced. On the basis of the accuracy assessment results, it appears that SVM generally outperformed the SAM classifier in both OA accuracy and individual classes' accuracies. OA accuracy and Kc for SVM is 96.93% and 0.9655, whereas for SAM it is 74.02% and 0.7085 respectively. SVM classification is the best in describing the spatial distribution and the cover density of each lithology, as was also indicated from the statistics of the individual class results. The individual class accuracy were also analyzed for the SVM and the result show that PA ranges from 87% to 100% and UA ranges from 91% to 100%, whereas for SAM ranges from 15% to 95%, and from 31% to 100% respectively. The SVM method could effectively classify and improve on the existing geological map for the Gadag schist belt (GSB) using hyperspectral data. The results could be validated through field visits. Therefore, it is concluded that hyperspectral remote sensing data can be efficiently used to improve existing maps, especially in areas where same rock types show variable degree of alteration over smaller spatial scales. [ABSTRACT FROM AUTHOR]

Time series of categorical variables often appear in Earth Science disciplines and there is considerable interest in studying their cyclic behavior. This is true, for example, when the type of facies, petrofabric features, ichnofabrics, fossil assemblages or mineral compositions are measured continuously over a core or throughout a stratigraphic succession. Here we deal with the problem of applying spectral analysis to such sequences. A full indicator approach is proposed to complement the spectral envelope often used in other disciplines. Additionally, a stand-alone computer program is provided for calculating the spectral envelope, in this case implementing the permutation test to assess the statistical significance of the spectral peaks. We studied simulated sequences as well as real data in order to illustrate the methodology. [ABSTRACT FROM AUTHOR]

Overheating is increasingly becoming a key issue for building design across the world. In the UK, better building fabric performance and warmer weather can increase the risk of overheating events in badly designed buildings. The impacts of these overheating events could be reduced by adapting building designs at an early design stage using building thermal models using appropriate weather data such as a design summer year. In this work, a method to determine probabilistic design summer years will be presented. These years take into account the return periods of actual events, are presented within a probabilistic framework and therefore include a description of the severity of the year at each location.Practical application: Design summer years are designed to be used to optimise building performance in terms of thermal comfort at design stage. This paper demonstrates a method to create probabilistic design summer years which contain a range of overheating events which can be used to inform designers of the overheating risk to occupants. The proposed method is then used to generate new near extreme weather files for the UK. [ABSTRACT FROM AUTHOR]

The easternmost part of Southwest Indian Ridge (SWIR) has special crustal structure, magmatic and tectonic processes. Abyssal peridotite from the easternmost part of Southwest Indian Ridge (63.5ºE/28ºS) is serpentinized spinel lherzolite. The accessory spinel has zoned texture, which was studied by petrography, electron probe micro-analysis (EPMA), and backscattered electron (BSE) imaging to reconstruct the petrotectonic and hydrothermal metamorphic history of the host abyssal peridotite. The fresh core is magmatic Al-spinel with low Cr. The average extent of melting of the abyssal peridotite is about 5.9%. The composition of fresh magmatic spinel core indicates the studied area to be an anomalously thin crust with a melt-poor system. Hydrothermal reaction modifies the chemical composition of magmatic spinel. Ferritchromit is the first product forming the inner rim during pre-serpentinization. The abyssal ferritchromit crystalized as micro- to nano-sized particle with no triple grain boundary, indicating they crystalized in a rapid cooling process during hydrothermal alteration. Chemical compositions of ferritchromit indicate a hydrothermal metamorphism in amphibolite facies. Magnetite in the outer rim was formed by replacement of ferritchromit during syn- or post-serpentinization. Authigenic chlorites crystallized in two events: (1) after formation of ferritchromit crystallized as vein in fracture-zone near the core of spinel and (2) after formation of magnetite crystallized at outermost rim. They are different in compositions, indicating their formation temperature was about 289 ºC and declined to 214 ºC. These results show that the abyssal peridotite had undergone amphibolite to lower-greenschist facies hydrothermal events during pre- to syn-serpentinization or post-serpentinization. [ABSTRACT FROM AUTHOR]

The microstructural and petrofabric study of peridotite xenoliths from the El Aprisco (Neogene Calatrava Volcanic Field) has provided new information on deformation mechanisms, ambient conditions and seismic properties of the central Iberian subcontinental mantle. Olivine, orthopyroxene, clinopyroxene, amphibole and spinel constitute the mineral assemblage in equilibrium. Their microstructure indicates that they accommodated crystal-plastic deformation under high water fugacity conditions. Crystallographic preferred orientation patterns of key minerals were determined with the EBSD technique. The xenoliths exhibit B, C and A olivine fabrics. B-type fabrics, involving the (010)[001] slip system, may develop in domains where deformation occurs under comparatively lower temperature, higher water-content and faster strain rates. They are interpreted here as the result of deformation in a suprasubduction mantle setting triggered by changing conditions imposed by a cooler subducting slab that incorporated fluids into the system. Xenoliths with olivine C-type fabrics involve activation of the dominant (100)[001] slip system, denote intracrystalline slip at higher temperatures and water-contents. They are here interpreted to sample lithospheric mantle domains where the impact of those new conditions was not so strong. Finally, the A-type fabrics, characteristic of the (010)[100] slip system, are frequent in the mantle under moderate to high temperature. These fabrics are considered here as characteristic of the mantle prior to subduction. The olivine fabrics constrain heterogeneous seismic properties. Propagation orientation of P waves (8.27–8.51 km/s) coincides with olivine [100] axis concentrations, whereas the fastest S1 waves (5.13–5.22 km/s) propagate parallel to [010] axis minima. The maximum shear wave birefringence (V S1 –V S2 = 0.17–0.37 km/s) is close to the direction of the macroscopic lineation. Heterogeneity of calculated seismic properties would concur with preservation of fossil flow perturbations, reworking and metasomatism in the subcontinental lithospheric mantle of central Spain, likely related to changes in the ambient conditions close to paleosubductions. [ABSTRACT FROM AUTHOR]

The influence of the relative shift between fabric layers on the local strain distributions at the mesoscopic scale of a four-layer plain weave glass fiber/epoxy matrix composite is studied through Finite Element (FE) modeling. The surface strain fields of several representative unit cells, consisting of compacted and nested plain weave layups with different layer shifts and the matrix complement, are compared to strain fields measured experimentally by digital image correlation. The layer shifts only have a small impact on the calculated homogenized macroscopic mechanical properties. However, the local strain fields are influenced significantly. Good quantitative agreement is obtained between the measured surface strain distributions and the numerical results if the layer shifts of the tested specimen are used in the FE model. The most frequently used models without layer shifts or with maximum nesting do not provide satisfactory surface strain distributions. [ABSTRACT FROM AUTHOR]