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England's 13,000 medieval churches are a distinctive landscape feature, not least because they were mostly constructed of local building materials. Especially prominent are churches incorporating iron-rich (ferruginous) stone, in a range of yellow-brown colours. This study investigates churches in an 1,800 km2 area centred on south Cambridgeshire, and interprets the distribution of three iron-rich building stones in space and time. Over 120 churches have been studied in the field, and a further sixty churches provisionally assessed using only photographs. The study confirms existing views that two iron-rich walling stones — the Ely and Gamlingay sandstones — were quarried from the bedrock Woburn Sands Formation (Lower Cretaceous). However, a third walling stone — the Cottenham Sandstone — is re-interpreted as a ferricrete (ironpan) formed by cementation of Quaternary river sediments by iron-rich ground-water. The churches containing ferricrete are shown to lie on the relict floodplains of the ancestral River Cam, rather than following the Woburn Sands outcrop. Cottenham ferricrete was used most commonly during the twelfth to fourteenth centuries with some reuse in the fifteenth and sixteenth centuries. This result conflicts with a hypothesis based on churches in the London Basin that ferricrete walling indicates a twelfth-century or earlier date. There is no evidence in the Romanesque and later churches of the study area that iron-rich and iron-poor building stones were used to create patterned rubble walling as a visual feature. The lack of patterning supports the view that such walls were not meant to be seen and were usually rendered or lime-washed. [ABSTRACT FROM AUTHOR]

PT. Mitra Karya Utama (MKU) adalah salah satu industri pengecoran logam di Ceper yang menggunakan pasir cetak greensand sebagai bahan cetakan utama dalam pembuatan produk utamanya yaitu Silinder Linier. Produk ini dipesan oleh konsumen secara terus menerus (kontinyu) dan berkelanjutan. Kendala yang dihadapi, dalam proses produksi silinder linier ini mengalami kendala yang mempengaruhi hasil produk silinder linier. Cacat produk tersebut mengakibatkan kurang baik dan kurang berkwalitasnya produk tersebut dan mengakibatkan kerugian. Tujuan dari program ini adalah untuk mengatasi masalah produksi dan meningkatkan mutu produk. Program dilaksanakan dengan melakukan aplikasi penggunaan face sand pada cetakan produk. Penggunaan facesand dilakukan dengan membina operator industri mitra. Hasil yang diperolah adalah penerapan facesand pada cetakan mampu meningkatkan kuantitas produksi dan menurunkan rejek produk menjadi 10%.

The geochemical composition of glauconitic clasts is a provenance marker to distinguish the origin of gravity flows in sedimentary basins. Their geochemical variation is visible in major and trace elements composition, where the former can be visualized by element mapping of glauconitic clasts. By applying automated quantitative mineralogy on a Scanning Electron Microscope equipped with the ZEISS Mineralogic™ software platform, we developed a new way to visualize the element distribution in selected minerals, while masking out the other minerals simultaneously. This software applies energy dispersive spectroscopy spectrum deconvolution for each analysis point, therefore quantitative concentrations (wt%) of each element are determined for each pixel and visualized in the false-coloured element map with reproducible results for individual grains and zonations in these grains. The investigated glauconitic clasts were collected from eleven drill cores, covering a 1400 m-depth interval, and crosscutting four different gravity flow members. The clasts show three different trends: first, cores of glauconitic clasts show a variation of compositions that are mainly dependent on the conditions during their formation. This is most visible for Si and Al. Secondly, the composition of the glauconitic clasts changes with depth, their cores become first more, than less Fe-rich and more K-rich. This is probably an alteration effect, depending on temperature, and therefore mineral stability. And, thirdly, most glauconitic clasts are zoned, where rims are richer in Al and poorer in Fe and K. The visualization of the chemical variation in the glauconitic clasts proofs to be a useful tool to separate these conflicting element exchange processes.

Abstract Although Oriente basin has explored throughout the past fifty years, little is known about the reservoir quality and hydrocarbon accumulation of the Cretaceous Upper T glauconitic sandstones. Until recently, the Upper T has drawn attention due to the commercial oil discovery. Howerer, exploration of glauconitic sandstones is complicated and reservoir quality is difficult to evaluate based on logging and seismic data. The glauconitic sandstones developed in open marine environments, characterized by a framework of glauconite and quartz grains. Diagenesis includes compation, silica overgrowth, feldspars dissolution, iron carbonate cementation. Its porosity ranges 5–20% and less than 500 md permeability. The dominant pore type is intergranular, especially residual intergranular. Glauconitic sandstones have bimodal pore throat size distributions and complex pore geometries. The Upper T glauconitic sandstones are capped by a thin veneer of fossiliferous limestones and laminated to burrowed shales. These large-area matured source rocks close to the glauconitic sandstones are probably the source kitchen in the slope of Oriente Basin. The oil pools are very little relation to structure. A large area of continuous developed glauconitic sandstone reservoirs and adjacent source rocks form an excellent source–reservoir–cap assemblage. Differ from previous views of long-distance migration from the southwest Oriente Basin, we propose that volume flow and diffusive flow are the primary migration and accumulation mechanism for the Upper T reservoir in Tarapoa Block. Graphical abstract Image 1 Highlights • Glauconitic sandstone is characterized by a framework of glauconite and quartz. • Glauconitic sandstone reservoirs are new commercial oil discovery in Tarapoa Block. • New accumulation mechanism about volume flow and diffusive flow is proposed. [ABSTRACT FROM AUTHOR]

We describe a new echinoid assemblage, composed of specimens of Bolbaster sp., Cyclaster danicus (Schlüter, 1897), Diplodetus vistulensis (Kongiel, 1950) and Linthia? sp. in a distinctive phosphatic preservation, from the so-called Greensand, a marly glauconitic sandstone horizon at the base of the Danian succession in the Kazimierz Dolny area (central Poland). This assemblage presumably is of early Danian age, with Cyclaster danicus occurring in the lower Danian of Denmark and southern Sweden. The specimens are preserved as internal moulds, composed of phosphatised glauconitic sandstone, occasionally with some test material adhering. The genesis of these moulds involved the following steps: (1) infilling of tests of dead echinoids with glauconitic sand,(2) penetration of the infills by coelobiotic deposit-feeding organisms that produced burrows along the inner test surface,(3) early-diagenetic cementation of infills by calcium phosphate,and (4) exhumation and intraformational reworking of specimens, leading to abrasion, fragmentation and loss of test material in some individuals. Co-occurring are unphosphatised moulds of Echinocorys ex gr. depressa (von Eichwald, 1866) and Pseudogibbaster cf. depressus (Kongiel in Kongiel and Matwiejewówna, 1937), which may represent a younger (middle to late Danian) assemblage. Additionally, the presence of derived late Maastrichtian echinoids, e.g., Temnocidaris (Stereocidaris) ex gr. herthae (Schlüter, 1892), Pleurosalenia bonissenti (Cotteau, 1866) and Hemicara pomeranum Schlüter, 1902, is confirmed for the Greensand, based on new material and re- examination of previously recorded specimens. In summary, members of three echinoid assemblages of different age and preservation occur together in the Greensand. Our results are compatible with former interpretations of this unit as a condensed, transgressive lag with mixed faunas of different age and provenance. However, they are incompatible with the hypothesis that phosphatised Danian fossils preserved in the Greensand are derived from a facies equivalent, now gone, of the lower Danian Cerithium Limestone in eastern Denmark, because all moulds are composed of phosphatised glauconitic sandstone that is utterly different from the calcareous dinocyst-dominated, fine crystalline matrix of the Cerithium Limestone. [ABSTRACT FROM AUTHOR]

Abstract Most of the excursions organised by the Geologists' Association in the late 19th C. and early 20th C. were essentially pedestrian in nature. However, around the turn of the 20th C. and up to the Great War (1914–1918), the Association experimented with either specific cycling-based excursions or those that accommodated the needs of cyclist excursionists. At the time, the Association, with its London base, was ideally placed to employ the railway network as the basis for its excursions. Railways were then the principal mode of transport for middle- and long- distance journeys and were increasingly promoting suburban expansion, creating potential new field excursion areas. The railways catered for those pedestrian excursionists and cyclists who wished to venture further afield from London than was previously possible on a day- or half- day trip. The notices and reports of excursions published by the Association are examined and critiqued. The cycling excursions are examined and contextualised within a combined technological and socio-historical framework; parallels are drawn with today. A re-examination of the excursions also provides a benchmark, useful for geoconservation purposes, of the availability and accessibility of historical geosites. It can underpin new self-guided geotrails suitable for use by a wider audience than traditional geological excursionists. These various themes are explored through the consideration of a specific 1905 excursion to Bedfordshire from which general conclusions are drawn. [ABSTRACT FROM AUTHOR]

To investigate the effects of preexisting flaws with different geometries, including flaw inclination angle and ligament angle on dynamic strength, deformation properties, and fracture evolution of rock materials, a series of dynamic impact tests were conducted on green sandstone specimens containing double elliptical flaws using a 75 mm diameter split Hopkinson pressure bar (SHPB) testing device with a high-speed camera recording in real time. The experimental results show that dynamic strength of specimens with different flaw angles is reduced between 5.91% and 39.92% but from 18.50% to 28.44% for specimens with different ligament angles, indicating that the effect of the flaw angle on the dynamic strength is more significant than that of the ligament angle. However, the dynamic deformation properties are influenced greatly by the ligament angle. Macroscale cracks mostly initiate at or near the flaw tips and then propagate in different paths with varying flaw geometries, leading to the ultimate failure in five typical modes based on the crack coalescence. Shear crack coalescence and tensile crack coalescence are identified through both macroscopic fracturing photos taken by the high-speed camera and microscopic surface morphology obtained by the scanning electron microscope (SEM). [ABSTRACT FROM AUTHOR]

Highlights • Manganese greensands performances were compared when activated with bleach and KMnO 4. • Removal performance was enhanced when using higher oxidant concentrations. • KMnO 4 increased greensand removal performance; bleach limited effect of reductive dissolution. • Activation induced a discrete removal mechanism involving a negative charged surface species. • XPS of activated media eluded the mechanism were analogous to Mn(VII). Abstract Manganese greensands are used routinely in industry for Mn(II) and Fe(II) removal from drinking water and groundwater, however little is understood about the effect of changing the activation conditions on removal performance. This study directly compared the change in removal performance for Mn(II) and Fe(II) across five commercially available greensands when using bleach or potassium permanganate as the oxidant for greensand activation. The performance of these medias when no activation process was employed was also compared. The results indicated that enhanced performance was achieved when higher concentrations of oxidant were used. Activating the medias with potassium permanganate was found to achieve slightly higher removal performance for both Mn(II) and Fe(II), although bleach was found to limit the effect of reductive dissolution when treating Fe(II) solutions. A notable observation was that activation of the medias induced a discrete removal mechanism that involved a negatively charge surface species. This species was thought to exist as a higher oxidation state than Mn(IV), analogous to a Mn(VII) species. XPS spectra indicated that activation influenced the greensands’ surface structure, and supported the change in surface Mn oxidation state, however the surface speciation was inconclusive as to an exact structure. This study used fixed bed columns to examine the various activation conditions, as well as XPS to observe any changes in Mn oxidation state. [ABSTRACT FROM AUTHOR]

The Upper Greensand Formation, mostly capped by the Chalk, crops out on the edges of a broad, dissected plateau in Devon, west Dorset and south Somerset and has an almost continuous outcrop that runs from the Isle of Purbeck to the Vale of Wardour in south Wiltshire. The Formation is well exposed in cliffs in east Devon and the Isle of Purbeck, but is poorly exposed inland. It comprises sandstones and calcarenites with laterally and stratigraphically variable amounts of carbonate cement, glauconite and chert. The sedimentology and palaeontology indicate deposition in marginal marine-shelf environments that were at times subject to strong tidal and wave-generated currents. The formation of the Upper Greensand successions in the region was influenced by penecontemporaneous movements on major fault zones, some of which are sited over E-W trending Variscan thrusts in the basement rocks and, locally, on minor faults. Comparison of the principal sedimentary breaks in the succession with the sequence boundaries derived from world-wide sea-level curves suggests that local tectonic events mask the effects of any eustatic changes in sea level. The preserved fauna is unevenly distributed, both laterally and stratigraphically. Bivalves, gastropods and echinoids are common at some horizons but are not age-diagnostic. Ammonites are common at a few stratigraphically narrowly defined horizons, but are rare or absent throughout most of the succession. As a result, the age of parts of the succession is still poorly known. [ABSTRACT FROM AUTHOR]

The Semri Group of the Vindhyan Supergroup contains widespread intrabasinal felsic volcanic rocks in the Porcellanite Formation formed during the early Mesoproterozoic. This widespread felsic volcanism was followed by the deposition of siliciclastic sedimentary rocks of the Kheinjua Formation containing the Olive Shale, Fawn Limestone, Glauconitic Sandstone members, the last one dominantly arkose and litharenite. The volcanic products resulting from volcanic activity during deposition of Porcellanite Formation were predominantly fine volcanic ash or dust that settled very slowly in the water column of the basin. The ranges of 28 elemental ratios for the Olive Shale and Glauconitic Sandstone members overlapped with those of the Porcellanite Shale Formation. The contemporaneous intermingling of the detrital input from volcanic products with the terrigenous detritus received by the basin from the Bundelkhand Craton in the north is reflected in the geochemical signatures. Various plots of elemental ratios and ternary plots for the siliciclastic rocks overlap those of the Porcellanite Shale Formation and Bundelkhand Tonalite‐trondhjemite‐granodiorite (TTG) suggesting that they might be the source rocks. The mixing of detritus from volcanic products was perhaps responsible for the widespread appearance of glauconite‐bearing sediments in the subsequent deposits. Glauconitization of detrital K‐feldspars, clay peloids, and volcanic lithic fragments is evident from the petrography. The shallow marine environment, slow sedimentation rates, elevated surface temperatures and mildly reducing conditions (CO2 got released from explosive volcanism) are considered as the favourable conditions for glauconitization, which prevailed within the Vindhyan Basin. Under these conditions the detrital input received as the result of previous volcanism during deposition of the porcellanite shale (glass, pumice lithic fragments, and feldspars) were transformed into clays such as illite and glauconite during the deposition of siliciclastic rocks of the Kheinjua Formation within the basin. [ABSTRACT FROM AUTHOR]

Wire and Arc Additive Manufacturing (WAAM) is a metal 3D printing technique based on robotic welding. This technique yields potential in decreasing material consumption due to its high material efficiency and freedom of shape. Empirical measurements of WAAM, using a deposition rate of 1 kg/h, were performed on site of MX3D. The measured power consumption per kg stainless steel is 2.72 kW, of which 1.74 is consumed by the welder, 0.44 by the robotic arm, and 0.54 by the ventilation. The material loss was 1.1%. A 98% argon 2% CO2 welding gas was used with a flow of 12 l/min. A cradle-to-gate Life Cycle Assessment (LCA) was performed. To give this assessment context, green sand casting and CNC milling were additionally assessed, through literature and databases. The purpose of this study is to develop insight into the environmental impact of WAAM. Results indicate that, in terms of total ReCiPe endpoints, the environmental impact of producing a kg of stainless steel 308 l product using WAAM is comparable to green sand casting. It equals CNC milling with a material utilization fraction of 0.75. Stainless steel is the main cause of environmental damage in all three techniques, emphasizing the importance of WAAM's mass reduction potential. When environmentally comparing the three techniques for fulfilling a certain function, optimized designs should be introduced for each manufacturing technique. Results can vary significantly based on product shape, function, materials, and process settings. [ABSTRACT FROM AUTHOR]

Five natural products – vermiculite, glauconite, straw ash, wood biomass and pork fertilizer are presented for the study and evaluation of the compost mixtures in different proportions. The aim of the study is to assess the impact on soil properties in pot experiments based on the characterization and evaluation of the composite mixtures of natural products. A vegetation experiment was conducted to determine the impact of compost mixtures on soil changes. Tested crops are silage corn and lettuce. The experiments were carried out on the Aluvial meadow from the Montana region and the HaplicVertisol from the Sofia region. Chemical and agrochemical characterization of Alluvial soil and Smolnitsa on which are derived pot experiments found, that after harvesting the crops most Impact of the third and fourth mixture. In these mixtures show a strong increase the amount of assimilable potassium.This creates limitations on recommending greater rates of fertilization above 7%. Five compost mixtures are quality enhancer for use in the agricultural practice. To recommend a rule must be considered and economic opportunities of the manufacturer, sufficient amount of source components and others. [ABSTRACT FROM AUTHOR]

Water flooding with selective ions has in some cases lead to increased oil recovery. We investigate the physical processes on a pore scale that are responsible for changes in petrophysical and mechanical properties of four oil-bearing chalk and four oil-bearing greensand samples caused by flooding with brines containing varying amounts of dissolved NaCl, Na 2 SO 4 , MgCl 2 and MgSO 4 . Ultrasonic P-wave velocity and AC resistivity measurements were performed prior to, during and after flow through experiments in order to identify and quantify the processes related to water flooding with selective ions. Low field Nuclear Magnetic Resonance (NMR) spectrometry measurements were performed at full water saturation, at irreducible water saturation, after aging and after flooding. CT-scanning, X-ray diffraction (XRD), backscatter electron microscopy images (BSEM), mercury injection capillary pressure (MICP) curves and specific surface analysis (BET) reveal the mineralogy and texture of the rock samples before and after the injection. Low field NMR data indicates changes in the pore fluid distribution and wettability of chalk after aging of one of the samples. NMR data for other samples indicate that chalk is water-wet after flooding. Greensand remained mixed wet throughout the experiments. Electrical resistivity data are in agreement with this interpretation. The electrical resistivity data during flooding revealed that the formation brine is not fully replaced by the injected water in both chalk and greensand. Changes in the elasticity of chalk during flooding illustrate the softening effect of magnesium bearing brines as compared to the sodium bearing brines. The stiffness of greensand was not affected by water flooding with selective ions as determined from the elastic wave measurements. Precipitation of fines during flooding of chalk samples is indicated by an increase in specific surface area and a shift in the MICP to lower values but no fines were detected by NMR. No changes were observed for greensand samples. [ABSTRACT FROM AUTHOR]

Greensand is a widely-used material to produce sand moulds in high production, mainly for iron casting applications. Several authors have studied the high temperature behavior of greensand regarding to the vapour condensation and transfer zones, and the effect of different production parameters on the thermal conductivity. This work focuses on the effect of the mixture composition on the heat absorption (cooling) capacity of the greensand. During the experimental work, various greensand mixtures with changing bentonite + water and coal dust contents were prepared and tested by a novel application of Fourier thermal analysis. The method provides new thermophysical knowledge about moulding sand, through applying real casting conditions by the immersion of spherical sand samples into liquid iron. The findings of the work direclty contribute to the area of thermal sciences and also brings novel understandings to foundry technology in general. [ABSTRACT FROM AUTHOR]

An evaluation studying the use of oxidation–reduction potential (ORP) for optimizing a 10,500 m³/d (2.8 MGD) oxidizing media filter (OMF) process treating Floridan groundwater containing between 1.6 and 1.8 mg/L sulfide has been completed. One year after placing the OMFs on-line, colored water complaints were reported within the municipal water system. It was determined that the filter beds required regeneration as they were insufficiently oxidized, and the media’s manganese dioxide coating was being released into the finished water. ORP, free chlorine residual, total manganese and turbidity measurements were recorded during filter run cycles before and after each regeneration event. Results showed that below 500 mV ORP was a more useful measurement for monitoring regeneration events within the media bed than chlorine residual which was not detectable. Results showed a significant increase in turbidity (>2 NTU) and total manganese (> 0.05 mg/L) when the ORP within the filter bed dropped below 400 mV. More frequent cycling of the filters was found to be an effective treatment option to maintain ORP values above 600 mV as an operational threshold. [ABSTRACT FROM AUTHOR]

This paper explores suitability of glauconitic rocks in the Upper Cretaceous Bakchar deposit in Western Siberia as alternate potash fertilizer. The K 2 O content of these glauconitic rocks varies from 2.5 to 4.1 wt.%, indicating their good potential as K-fertilizer for agronomic uses. According to the different compositional and textural characteristics, glauconitic rocks can be divided into three types, i.e., glauconitolite, glauconitic sandstone and glauconite-chamosite ooidal ironstone, with glauconite concentrations 58.5 wt.%, 25.7 wt.% and 24.6 wt.%, respectively. The intermediate size fraction of glauconitolite concentrates up to 90.4 wt.% of glauconite grains by using wet sieving. Magnetic separation further increases the concentration of glauconite grains for each type of rock samples, especially of glauconitic sandstone. Mixing of glauconitic products with soil increases the germination rate of oat seeds by up to 5.2%, the seedling height records an increase from 0.8% to 18.8%. Both untreated glauconitolite and its granulometric fraction result same rate of growth of oat seedlings. The results of this study suggest that the Bakchar glauconitic deposit can be used as a substitute potash fertilizer, with or without sieving and magnetic separation. [ABSTRACT FROM AUTHOR]

At its maximum development in the type area on the Devon coast, the Upper Greensand Formation comprises up to 55 m of sandstones and calcarenites with laterally and stratigraphically variable amounts of carbonate cement, glauconite and chert that were deposited in fully marine, shallow-water environments. The formation is divided into three members, in ascending order the Foxmould, Whitecliff Chert and Bindon Sandstone, each of which is bounded by a prominent erosion surface that can be recognised throughout the western part of the Wessex Basin. The full thickness of the formation, up to 60 m, was formerly well exposed in cliffs in the Isle of Purbeck in the steeply dipping limb of the Purbeck Monocline. The upper part of the succession is highly condensed in comparison with the Devon succession and exhibits lateral variations over distances of hundreds of metres that are probably related to penecontemporaneous fault movements. Much of the fauna is not age-diagnostic with the result that the ages of parts of the succession are still poorly known. However, the Isle of Purbeck sections contain diverse ammonite faunas at a few stratigraphically well-defined levels that enable the succession to be correlated with that of east Devon and west Dorset. [ABSTRACT FROM AUTHOR]

Glauconite segregations in Oligocene-Miocene shelf sediments of Western Kamchatka (Kakert and Gakkha horizons) are studied. Glauconite occurs in the studied samples as morphologically different grains, finely dispersed cement, and pseudomorphoses after organogenic structures (siliceous sponge spicules, diatom algae frustules, and others). In addition, samples of the clasts of bryozoans, volcanic glass, and terrigenous grains revealed for the first time traces of the boring algae similar to recent species of genus Hyella and, possibly, Dalmatella, whose tubules are sometimes filled with the finely dispersed glauconite. Our data based on the detailed petrographic studies and SEM investigations confirm and supplement the opinion of several researchers about an important role of microbiota on the glauconite formation. The paper discusses different stages of the glauconite formation in sediments of the Kakert and Gakkha horizons and the possible setting of glauconite infilling in the algal borer trails and holes. [ABSTRACT FROM AUTHOR]

This study investigated the fundamental performance of manganese greensands for the removal of both dissolved manganese and iron species from solution. The hypothesis was that iron ions may detrimentally impact manganese removal and that the magnitude of this outcome was dependent upon greensand composition. Consequently, five greensand materials were examined in terms of repeatability of operation, the relationship of performance to physical criteria, the mechanism of removal, influence of solution pH and the performance changes that occur when manganese and iron were co-present in solution. All greensand medias were shown to remove Mn(II) over 5 treatment cycles, where the solid MnO 2 media had a larger removal capacity (0.35 mg/g) compared to the two coated medias (0.09 and 0.05 mg/g, respectively). The greensand medias also showed a significant capacity reduction from 72 to 93% when Fe(II) containing solutions were examined. Fe(II) species were also found to leach considerable amounts of Mn(II) through reductive dissolution which negated the beneficial Mn(II) removal when treating solutions with co-present Fe(II) and Mn(II). Material characterization revealed that the Mn(II) removal mechanism did not involve any surface MnO 2 phase change or rely solely on Mn(II) adsorption. [ABSTRACT FROM AUTHOR]

Potassium is one of the important nutrients for healthy growth and development of plants. This article explores the possibility of extracting potassium from lean grade indigenous glauconitic sandstone, which is locked in the host matrix. Detail physico-chemical and mineralogical characterization of glauconitic sandstone collected from Guneri area of Kuchchh district, Gujarat (India) was carried out by X-ray diffraction (XRD), Scanning electron microscopy (SEM) followed by Energy-dispersive X-ray (EDX), X-ray fluorescence (XRF), Atomic absorption spectrometer (AAS) and conventional analytical tools. The major matrix of glauconite sample was found to contain 3.93% K 2 O, 10.75% Fe 2 O 3 , 4.41% Al 2 O 3 and 70.35% SiO 2 . The K 2 O content could be enriched from 3.93% to 5.52% by simple screening and rejection of +425 μm particles fraction. Chemical leaching of enriched fraction with hydrochloric acid (HCl) yields very low recovery (<12%) of potassium. Therefore, a combined reduction roasting-leaching method was developed to recover potassium chloride suitable for fertilizer application. The effects of roasting temperature, coke to glauconite ratio during roasting and various leaching parameters such as acid concentration, leaching time and temperature during dissolution of potash were studied. Parameters have been optimized to achieve more than 98% potassium recovery along with recovery of iron value as magnetite. [ABSTRACT FROM AUTHOR]

"Halitherium" bellunense is exclusively known from a single individual from upper Oligocene glauconitic sandstone near Belluno, northern Italy. According to a review of its morphological basis, which consists of associated cranial elements, some vertebrae and ribs, this specimen is identified as a juvenile, because the first upper incisor (I1) and supposedly second upper molar (M2) are not fully erupted. However its juvenile status allowed only cautious conclusions on its taxonomy and systematic affinity. The presence of a nasal process of the premaxilla with a broadened and bulbous posterior end, and a lens-shaped I1, corroborate an evolutionarily-derived status of this species that places it well within the sirenian crown group Dugonginae. Considering these new data and in order to avoid continued misuse of the inappropriate generic name of Halitherium, a new generic name, Italosiren gen. nov., and emended species diagnosis are supplied for this taxon. [ABSTRACT FROM AUTHOR]

The study describes the degradation of inkjet ink at low frequency ultrasound (US) and greensand to compare their reactivity. Environmental sonochemistry is a rapidly growing area and an example of the advanced oxidation process (AOP) that deals with the destruction of organic species in aqueous solutions. Greensand is a granular material coated with a thin layer of manganese dioxide (MnO2) which is among the strongest natural oxidants. In our study magenta inkjet water-based printing ink was dissolved in distilled water and the solutions obtained after degradation were analysed in terms of total organic compound (TOC) and absorption curves in the visible spectra. Also used for the process monitoring was high performance liquid chromatography (HPLC). The efficiency of discoloration is significantly affected by the effluent pH. The efficiency of discolouration was higher when the pH of initial solution was 2 with respect to the initial solution pH of 5.5. In all solutions, irrespective of the initial pH value and the processing method the oxidation of polyhydric alcohols occurs. Although the decomposition is significant, surface peaks resulting from HPLC analysis are very small. Decolourization is closely related to the cleavage of the - C=C and -N=N- bonds, and oxidation of polyhydric alcohol to the formation of monosaccharides, carboxylic acids or other low molecular weight compounds with a lesser number of unsaturated double bonds. These compounds have low UV absorbance or they absorb below 200 nm and therefore their detection is impossible. Thus, the obtained total organic compound results indicate a small degree of mineralization. The effectiveness of the low-frequency ultrasound (20 kHz) oxidation is similar to the effectiveness of oxidation by greendsand. [ABSTRACT FROM AUTHOR]

The discrete element method (DEM) is applied to simulate the dynamics of the flow of green sand while filling a mould using the DISAMATIC process. The focus is to identify relevant physical experiments that can be used to characterize the material properties of green sand in the numerical model. The DEM parameters describing the static friction coefficients are obtained using a ring shear tester and the rolling resistance and cohesion value is subsequently calibrated with a sand pile experiment. The calibrated DEM model is used to model the sand shot in the DISAMATIC process for three different sand particle flow rates as captured on the corresponding video footage of the interior of the chamber. A mould chamber with three ribs mounted on the fixed pattern plate forming four cavities is chosen as a reference geometry to investigate the conditions found in the real moulding process. The geometry of the cast part and the casting system can make the moulding process complicated due to obstacles such as ribs that deflect the sand flow causing “shadows effects” around the cavities of the mould. These dynamic effects are investigated by the qualitative flow dynamics and quantitative mould filling times captured in the video footage and simulated by the calibrated DEM model. Both two- and three-dimensional DEM models are considered and found to produce results in good agreements with the video footage of the DISAMATIC process. [ABSTRACT FROM AUTHOR]

The Tortonian sedimentary succession of Menorca Island (Balears, Spain) includes two stratigraphic sequences: the lower Tortonian distally-steepened carbonate ramp and the coral reef complex of late Tortonian-early Messinian age. The boundary between the two sequences corresponds to Heterostegina -rich sediments in the western part of Menorca, and to a phosphatic hardground in the eastern part of the island. In the field, the hardground is represented by a dark-brown layer and a rough surface on top of the Tortonian Ramp deposits. Dark phosphate precipitates infill cracks and borings in the underlying limestone to a depth of up to 50 cm. The phosphatic hardground is overlain by planktonic rich wackestone to packstone, which penetrates downward into the fissures, borings, and vugs. This deposit is characterized also by grains of reworked phosphate, glauconite grains, small benthic foraminifers and is followed by tabular beds of bioclastic packstone to wackestone with abundant thin crusts of coralline algae. Based on the Amphistegina tests shapes and red algal assemblage of sediments below and above the hardground, and the lateral correlation with Heterostegina deposits, the bathymetry for the development of the phosphatization is estimated less than 100 m. The limited localization of the phosphatic hardground at the eastern side of the ramp indicates that a dynamic upwelling of deeper and nutrient-enriched waters favored development of a phosphatic hardground. This upwelling episode is representative of the paleoceanographic settings induced by the climate conditions of the Mediterranean area during the Tortonian. [ABSTRACT FROM AUTHOR]

The article presents research results of physico-chemical and environmental issues for the dust generated during dedusting of the installation for the processing and preparation of moulding sand with bentonite. Particular attention was paid to the content of heavy metals and emission of gases from the BTEX group, which is one of the determinants of the moulding sands harmfulness for the environment. The analysis of heavy metals in the test samples indicate that there is an increase of the content of all metals in the dust compared to the initial mixture of bentonite. The most significant (almost double) increase observed for zinc is probably related to the adsorption of this element on the dust surface by contact with the liquid metal. The study showed, that dust contained more than 20% of the amount of montmorillonite and had a loss on ignition at a similar level. The addition of 1% of dust to the used moulding sand results in almost 30% increase in the total volume of gases generated in casting processes and nearly 30% increase of the benzene emission. [ABSTRACT FROM AUTHOR]

The need for control of raw materials is critical to the success of iron casting production from greensand systems. The base silica sand is often overlooked with the main focus on bentonite additions.Carbonaceous additives can be considered a “necessary evil” to ensure a good surface fi nish and reduction in sand related surface defects. Other additives are used when systems get out of balance and these in turn add further to the complex nature of greensand systems.For castings requiring cores this becomes a bigger issue as many differing resin systems are employed for core production and these must be taken into consideration when controlling both the carbonaceous levels and the overall grading of the sand system. The twin effects on additional carbon and loss-on-ignition and overall sand grading need careful understanding and control. Various control methods are examined including traditional methods such as volatiles and loss-on-ignition along with bentonite determination methods and grading methods. Newer control methods such as total carbon are reviewed along with the overall package of testing and control methods. Various predictive methods are looked at as a control feature as well.The quality of additives and their role and more importantly their interaction is highlighted, as this is an area often neglected as foundrymen battle for success in consistent quality castings. Suggested in-coming control tests are discussed allied to additions at the mixer. Also reviewed is the interpretation of results and the action required to ensure control and more importantly consistent quality castings from greensand systems with the emphasis on the understanding and control of carbonaceous additive on casting performance.

Two Late Cenomanian - Early Turonian (C-T) intervals of the eastern part of the Kopet-Dagh basin, NE Iran have been investigated to evaluate the response of planktonic foraminifera to the geological event OAE2. The Gharesu and Taherabad sections with the thicknesses of 30 m and 22.5 m are composed of shale and marl interbedded with glauconitic sandstone. Three biozones Rotalipora cushmani, Whiteinella archaeocretacea and Helvetoglobotruncana helvetica were recognized based on study of planktonic foraminifera, in these sections. We observed the patterns of planktonic foraminiferal assemblage changes around the C-T boundary and divided this succession into several successive intervals. This study confirms that OAE2 was a long term event. A gradual perturbation in the study successions starts in the interval 1 with low abundance and diversity of planktonic foraminifera. An enhanced oxygen minimum zone (OMZ) occurs in the interval 3 which coincides with a temporary absence of planktonic foraminifera and sedimentation of framboidal pyrite. High diversity of planktonic foraminifera and appearance of new genera in the interval 5 indicate return of normal conditions to the basin. A significant short-term sea surface temperature cooling is also indicated by planktonic foraminiferal turnover and carbonate contents in the interval 2 which is comparable with other parts of the Tethys Ocean, Boreal sea and Atlantic region. [ABSTRACT FROM AUTHOR]

In the N.-W. Mediterranean area, the development of the Neolithic way of life during the 6th millennium cal. BCE is related to the spread of sailing pioneer groups. In the course of the 5th millennium cal. BCE, more stable agro-pastoral settlements expand their hold on the hinterland and exchange networks increase in complexity (obsidian, flints, clastic rocks). Although previous research showed high variability in the N.W. Mediterranean Neolithic diffusion modalities, the place of colouring materials, naturally abundant in this area, has received scant attention despite their technical and symbolic value. With the aim of assessing the place of these materials in the initial Neolithic package and within the development of the neolithisation process, we investigated series of more than 2000 blocks of colouring materials from two key-sites (Pendimoun and Giribaldi) recently excavated by one of us (DB), with dates ranging from 5750 to 3650 cal. BCE. This study was implemented by geological surveys that allowed the establishment of cartography of putative sources of raw colouring materials and the determination of their nature and composition. Combining petrographic examination and physico-chemical-characterisation (SEM-EDS, XRD), we determined a wide range of raw materials: psammitic sandstone, allochthonous and parallochthonous bauxite, oolithic ironstone, oxidised marcasite and ferruginous rocks derived from weathered glauconitic limestones. Comparing archaeological series to this frame of reference highlights two contrasting economic systems: one based on exploitation of local sources from the Early to the Middle Neolithic, the other one founded on a dual use of both close geomaterials and exogenous rocks during Middle Neolithic. [ABSTRACT FROM AUTHOR]

The Turonian successions of the southern Corbieres comprise three transgressive-regressive cycles in which ammonites occur in three intervals. The lowest comes from the glauconitic basal transgressive unit of the first cycle, and comprises 21 species, including Kamerunoceras douvillei (Pervinquiere, 1907), Kamerunoceras turoniense (d'Orbigny, 1850), Spathites (Jeanrogericeras) revelerianus (Courtiller, 1860), Spathites (Jeanrogericeras) combesi (d'Orbigny, 1856), Mammites nodosoides (Schluter, 1871), Mammites powelli Kennedy, Wright and Hancock, 1987, Fagesia tevestensis (Peron, 1896), Neoptychites cephalotus (Coutiller, 1860), Thomasites rollandi (Thomas and Peron, 1889), Wrightoceras wallsi Reyment, 1954, and Choffaticeras (Choffaticeras) quaasi (Peron, 1904). This is a Lower Turonian assemblage referred to the Mammites nodosoides Zone, although the possibility that elements from the preceding Fagesia catinus Zone are also present cannot be excluded. The fauna from the transgressive glauconitic interval of the succeeding cycle comprises nine species, including Romaniceras (Romaniceras) mexicanum Jones, 1938, Romaniceras (Yubariceras) ornatissimum (Stoliczka, 1864), Pseudotissotia galliennei (d'Orbigny, 1850), Collignoniceras woollgari (Mantell, 1822) sensu lato, Coilopoceras springeri Hyatt, 1903, and Eubostrychoceras (Eubostrychoceras) saxonicum (Schluter, 1872). They indicate the Middle Turonian Romaniceras (R.) mexicanum and R. (Y.) ornatissimum zones. The highest fauna, from the Marnes superieurs de Saint-Louis of the Saint-Louis syncline, is: Subprionocyclus sp. juv., Prionocyclus sp. and Worthoceras cf. rochatianum (d'Orbigny, 1850). The Subprionocyclus are minute individuals that resemble S. bravaisianus (d'Orbigny, 1841), and suggest the presence of the lower Upper Turonian bravaisianus Zone. [ABSTRACT FROM AUTHOR]