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Rare earth element (REE) fluorocarbonate mineralization occurs in lacustrine shales in the Lower Devonian Rhynie chert, Aberdeenshire, UK, preserved by hot spring silicification. Mineralization follows a combination of first-cycle erosion of granite to yield detrital monazite grains, bioweathering of the monazite to liberate REEs, and interaction with fluorine-rich hot spring fluids in an alkaline sedimentary environment. The mineral composition of most of the fluorocarbonates is referable to synchysite. Mineralization occurs at the surface, and the host shales subsequently experience maximum temperatures of about 110 ℃. Most fluorocarbonate mineralization originates at much higher temperatures, but the Rhynie occurrence emphasizes that low-temperature deposits are possible when both fluorine and REEs are available from granite into the sedimentary environment. [ABSTRACT FROM AUTHOR]

The Paleoproterozoic schists of the Leverburgh Belt, South Harris and the Neoproterozoic carbonaceous metasediments of the Dalradian Supergroup were deposited during the two most significant periods of black shale deposition globally. Hosted within these metasedimentary rocks are graphite-bearing mineralised plutons, formed during orogenic events. The assimilation of carbonaceous lithologies during magmatic pluton emplacement is a commonly recognised mechanism in the formation of many metal and semi-metal-enriched deposits. Graphite mineralisation as a result of carbon assimilation is a feature often associated with these mineral deposits, though the source of the carbon and any associated metal deposits is not always understood. In this study, carbon and sulphur isotope analyses demonstrate that the crustal assimilation of the Paleoproterozoic host rocks took place during magmatic emplacement and provided the source of carbon and sulphur during mineralisation of the plutons. Minor enrichments of trace elements are present in the South Harris plutonic lithologies, indicating that mobilisation and enrichment occurred during assimilation of the schists. Petrographic and elemental analysis of a Dalradian-hosted Ordovician pluton indicates a similar but more substantial enrichment of these trace elements during crustal assimilation. The timing and depth of assimilation appear to play key roles in the extent of graphite and associated trace element enrichments. [ABSTRACT FROM AUTHOR]

We investigate four contributors to crisis readiness: market turbulence, innovative capacity, perceived likelihood of a crisis (PLC) and firm size. Results from a PLS‐SEM assessment of 284 managers in the United States suggest that market turbulence is not only a precursor to crisis readiness but also affects PLC and innovative capacity in firms. We conclude that managers in SMEs were more likely to expect a crisis but less prepared to address one when it strikes. [ABSTRACT FROM AUTHOR]

The scientific aims of the ExoMars Raman laser spectrometer (RLS) include identifying biological signatures and evidence of mineralogical processes associated with life. The RLS instrument was optimised to identify carbonaceous material, including reduced carbon. Previous studies suggest that reduced carbon on the Martian surface (perhaps originating from past meteoric bombardment) could provide a feedstock for microbial life. Therefore, its origin, form, and thermal history could greatly inform our understanding of Mars' past habitability. Here, we report on the Raman analysis of a Nakhla meteorite analogue (containing carbonaceous material) that was subjected to shock through projectile impact to simulate the effect of meteorite impact. The characterisation was performed using the RLS Simulator, in an equivalent manner to that planned for ExoMars operations. The spectra obtained verify that the flight‐representative system can detect reduced carbon in the basaltic sample, discerning between materials that have experienced different levels of thermal processing due to impact shock levels. Furthermore, carbon signatures acquired from the cratered material show an increase in molecular disorder (and we note that this effect will be more evident at higher levels of thermal maturity). This is likely to result from intense shearing forces, suggesting that shock forces within basaltic material may produce more reactive carbon. This result has implications for potential (past) Martian habitability because impacted, reduced carbon may become more biologically accessible. The data presented suggest the RLS instrument will be able to characterise the contribution of impact shock within the landing site region, enhancing our ability to assess habitability. [ABSTRACT FROM AUTHOR]

Graphite deposits may form alternatively by metamorphism of sedimentary rocks and from fluids. Both types occur in supracrustal successions within the Lewisian Complex of Northwest Scotland, and similarly in Palaeoproterozoic supracrustal rocks across the North Atlantic region in Canada, Greenland and Scandinavia. Carbon isotope compositions show that the graphite in Scotland had a mixed origin from metamorphism of sedimentary organic matter (schists) and the decarbonation of limestones (marbles). Raman spectroscopy shows that most of the graphite in Scotland exhibits some structural disorder, unlike the complete order in graphite vein ore deposits across the region. Exceptionally, where graphite was precipitated from fluid, in albitized rock in Tiree and Scardroy, it is fully ordered. While organic matter may survive granulite facies metamorphism without being transformed to fully ordered graphite, it can yield commercially more valuable ordered graphite when mobilized in a fluid. [ABSTRACT FROM AUTHOR]

The Capstone business strategy simulation has been used in business schools throughout the world. Scholars have investigated the impact of Capstone and other simulations on student learning, but there are no published studies that investigate factors associated with success. This study examines the performance of 7,347 participants using Capstone in 2019. Results suggest an optimal team size of four students. Overall, teams performed better in the competition mode than in the footrace mode, and better in official rounds than in practice rounds. Completion of training modules was associated with improved team performance in some but not all instances. [ABSTRACT FROM AUTHOR]

The episode of widespread organic carbon deposition marked by peak black shale sedimentation during the Palaeoproterozoic is also reflected in exceptionally abundant graphite deposits of this age. Worldwide anoxic/euxinic sediments were preserved as a deep crustal reservoir of both organic carbon, and sulphur in accompanying pyrite, both commonly >1 wt %. The carbon- and sulphur-rich Palaeoproterozoic crust interacted with mafic magma to cause Ni–Co–Cu–PGE mineralization over the next billion years, and much uranium currently produced is from Mesoproterozoic deposits nucleated upon older Palaeoproterozoic graphite. Palaeoproterozoic carbon deposition has thus left a unique legacy of both graphite deposits and long-term ore deposition. [ABSTRACT FROM AUTHOR]

Proterozoic limestone in a north British terrane contains a newly recognised occurrence of Nb-REE minerals. The mineralized Loch Shin Limestone is in the Lewisian Complex of the Northern Highlands of Scotland, intruded by alkaline plutons above a Caledonian (∼0.43 Ga) subduction zone. The mineral assemblage includes columbite, calcium niobate minerals, and niobian rutile and also includes W- and Sn-bearing phases. The interval between limestone deposition and mineralization was over a billion years. Other limestones in the Lewisian Complex that were not affected by alkaline plutons are not mineralized by Nb. The occurrence indicates that there may be exploration potential for Nb in limestones mineralized by hydrothermal activity above subduction zones with alkaline intrusions. [ABSTRACT FROM AUTHOR]

This study investigates political nonmarket strategy (NMS) by addressing its links to market strategy, values orientation, and multiple dimensions of firm performance – competitive positioning, customer orientation, and financial outcomes – in the Hong Kong hotel industry. Data were collected from hotel managers and analyzed utilizing partial least squares (PLS) methods. Cost leadership was identified as a driver of financial performance in Hong Kong, while differentiation based on quality appears to help firms in terms of competitive positioning but drives neither financial nor customer-based performance. Political NMS helps firms with competitive positioning and customer orientation but does not appear to drive financial performance. Values orientation was identified as a significant driver of all three dimensions of firm performance. [ABSTRACT FROM AUTHOR]

The direct measurement of gases trapped in sulphide minerals shows that samples from gold-bearing deposits in Britain and Ireland are anomalously rich in methane. Chalcopyrite samples in deposits of Palaeozoic age sited in Neoproterozoic basement (Caledonides greenschist), Munster Basin (Variscides greenschist) and the Carboniferous cover (diagenetic) were compared using mass spectrometry of cold-crushed gases. All host sequences contain sources of organic matter. The content of non-aqueous gas is greater in both sets of greenschist-hosted deposits than in the diagenetic-hosted deposits. However, chalcopyrite accompanying gold in the Neoproterozoic is methane-rich, but in the low-gold Munster Basin it is methane-poor. These gas data from opaque minerals complement fluid inclusion data from gangue minerals, and add support to models for the involvement of organic species in orogenic gold mineralisation. [ABSTRACT FROM AUTHOR]

Much silica precipitation in oil reservoirs occurred in the presence of hydrocarbons, evidenced by the entrapment of oil fluid inclusions in quartz. Also, silica in sedimentary basins is commonly precipitated at oil‐window temperatures. This spatial and temporal relationship between oil and quartz precipitation aids the entry of oil into fractured reservoirs, including fractured basement. Where quartz is precipitated as fracture linings, the fractures are propped open by bridging quartz crystals, creating high fracture porosity and permeability. Evidence from fossil fractured reservoirs shows a large proportion of oil residue is in such propped open fractures. [ABSTRACT FROM AUTHOR]

Thanks to the pioneering research of Paul Younger over the past 20 years, acid mine drainage in the UK has been recognized as a major environmental issue. Acid mine drainage and hydrous ferric oxide deposition are environmental hazards resulting from centuries of extensive coal mining activities across the UK. Oxidative weathering of pyrite in coal from spoil heaps and exposed bedrock can liberate trace elements, releasing them into local water systems. In addition to posing an environmental threat through water and ground contamination, ochres can also act as a remediation material, trapping elements such as selenium. Trace elements with a close association to iron oxides, such as selenium, may fix to the fine‐grained ochre materials, resulting in hyper‐enriched ochres. Selenium in coals has been known to cause an environmental issue in areas of North America but is also an important commodity for solar cells and nanotechnologies. Coal‐bearing areas of the UK, such as Northumberland, are known to contain a high selenium content, and coal‐derived ochres in these regions also contain significant selenium. The widespread occurrence of ochres in UK coal‐mining regions may therefore present a unique 'E tech' trace element source and prevent a toxicity problem for which they were once thought to be responsible. [ABSTRACT FROM AUTHOR]

Rand's philosophy of objectivism has enjoyed a recent resurgence of interest in the United States, but little is known about how it is conceptualized in non-Western cultures and how it influences business practice. This paper investigates and supports the existence of a form of objectivism within the Chinese culture, drawing into question the notion that Chinese society is inherently collective. Results concerning an anticipated metaphysical dimension were inconclusive, suggesting that Chinese who embody epistemological, ethical, and political aspects of objectivism lack a corresponding and clear notion of causality, time, and identity. [ABSTRACT FROM AUTHOR]

Standard mode and collision/reaction cell mass spectroscopy methods have been utilized in order to overcome spectral interferences and provide ultra‐low quantification of selenium (Se) and tellurium (Te) in British Carboniferous coals for the first time. The accurate detection of Se and Te in coals is becoming increasingly important, as coals and pyrite have been identified as potentially significant trace element sources. The mean Se concentration of British coals bear comparison to that of world coals, with anomalous Se content (concentrations above 4 mg/kg) across westerly exposures, often coinciding with high sulphur (S) content and visible pyrite. New Te data for British coals gives a mean concentration of 0.02 mg/kg, with anomalous Te in Ayrshire. There is a positive correlation in the Te/Se ratio across the sample set. The close relationship between Se and Te, as well as Se–Te with both early syngenetic and later cleat‐filling pyrite, confirms an important role for sulphides in Se and Te sequestration in British coals. The high Se‐Bowland Shale and/or Ordovician volcanics may have provided the trace element source for British coals of similar or younger age. Regional intrusive activity (shallow tabular intrusions or more extensive plutons) and episodes of intense deformation can alter the thermal maturity of coals and may have driven the movement of trace element‐rich fluids through strata, locally enriching coals in Se and Te. [ABSTRACT FROM AUTHOR]

Abstract The distribution of oil residues in fractured Upper Devonian reservoir sandstones of Caithness help us to understand relationships between oil charge and episodes of fracturing. The sandstones are cut by an extensive set of tightly cemented deformation bands in the vicinity of the Brough Fault, and calcite-mineralized open fractures. The deformation bands compartmentalized the reservoir, which subsequently was charged by oil to varying extent in different compartments. Petrographic and biomarker data distinguish two charges of oil. The first charge of oil was unaltered. The later mineralized fractures introduced a heavier biodegraded oil that spread into the sandstone pores and displaced/overprinted the earlier oil. Two distinct oil charges are also evident from two generations of oil fluid inclusions, firstly in overgrowths on quartz grains, and secondly in the calcite veins, exhibiting distinct fluorescence characteristics. Migration and trapping of oil depended on the combination of two fracturing episodes of different character, in which the first episode created sealed compartments which were then filled by oil introduced by the second episode. Highlights • Onshore exposure of oil-charged reservoir. • Geochemistry shows two stages of oil charge. • Second stage oil charge is more biodegraded. • Two stages of fracturing: deformation bands and later mineralized fractures. • Study places stages of oil charge and fracturing into sequence of events. [ABSTRACT FROM AUTHOR]

Abstract Primary and secondary porosity in sandstones possess different pore geometry characteristics, but these are not well quantified. The pore surface area in 2 suites of sandstones exhibiting only primary porosity (Permo-Triassic, Northern Ireland) and only secondary porosity (Cambrian, England) were measured using JMicrovision software. The data show pore surface areas per unit pore volume ∼2.5 times as great in the secondary porosity compared to the primary porosity. This difference is great enough to have a significant impact on properties dependent on pore surface area, including oil production and capacity for microbial colonization in the deep biosphere. Highlights • Secondary pores after feldspar dissolution in sandstones has high pore surface area. • Sandstone secondary porosity has about 2.5 x the surface area in primary porosity. • If 40% of the total porosity is secondary the pore surface area is increased by 60%. [ABSTRACT FROM AUTHOR]

This paper presents a revision of Uvaria L. (Annonaceae) in continental Asia and outlying islands, north of the Thailand–Malaysia border, on the basis of a combination of new morphological analyses and recent phylogenetic data. Two new taxonomic groupings are defined within the genus in Asia on the basis of detailed morphological character analysis in ~1800 specimens. Stamen and carpel structure are shown to be significantly more informative than calyx and corolla characters for subgeneric differentiation, and reliably discriminate basal and derived radiations when mapped onto recent molecular phylogenies for the genus in Asia. Thirty-three species and species varieties are recognised within Uvaria in continental Asia, incorporating taxa formerly assigned to Anomianthus Zoll., Cyathostemma Griff., Ellipeia Hook.f. & Thomson, Ellipeiopsis R.E.Fr. and Dasoclema J.Sinclair. Four new combinations are proposed, and outstanding taxonomic, nomenclatural and typification issues are resolved for included taxa. Keys for both flowering and fruiting material are included, and distribution data are provided for all taxa. [ABSTRACT FROM AUTHOR]

The Carboniferous Lower and Middle Coal Measures coals of the Northumberland Coalfield are anomalously rich in selenium (Se) content (up to 62 ppm) compared to the averages for the common UK and worldwide coals. As well as posing an environmental toxicity threat, Se is now regarded as an important resource for alloys, photovoltaic products and nanotechnologies, and high Se coals in North East England offer an opportunity to assess the Se means of occurrence, origins, transport mechanisms and enrichment in coals. At least two generations of pyrite host high Se in the sampled coal seams: microbial-formed disseminated pyrite (both cubic and framboidal in habit) and later cleat-filling pyrite, identified by petrographic observations, laser ablation methods and sulphur isotope compositions. There is a notable Se enrichment of up to 250 ppm in later formed cleat-filling pyrite. Trace element enrichment may have been sourced and influenced by seawater distribution during diagenesis, and localised dykes and deformation may have acted as an enrichment mechanism for sampled seams in the region. The high Se coals in Northumberland may provide a potential E tech element source and should be considered and carefully managed as coal mining and production are reduced in the area. The study also highlights the nature of Se enrichment in pyritic coals affected by cleat formation and multiple episodes of mineralisation, important as critical element demand continues to increase worldwide. [ABSTRACT FROM AUTHOR]

Abstract: Black shales of the late Neoproterozoic Gwna Group (570–580 Ma), UK, contain enrichments of tellurium (Te), selenium (Se) and cobalt (Co) relative to average shale compositions. The Te and Co enrichments bear comparison with those of ferromanganese crusts in the modern deep ocean. Gwna Group deposition coincides with the Second Great Oxidation Event, which had a significant effect on trace element fixation globally. Selenium and Te concentrations within these black shales indicate increased continental weathering rates, high biological productivity and corresponding increases in atmospheric O2 concentrations. Cobalt, nickel (Ni) and arsenic (As) enrichments in this succession are secondary mineralisation phases. Demand for many of the trace elements found enriched in the Gwna Group black shales make their mechanisms of accumulation, and variations through the geological record, important to understand, and suggests that new resources may be sought based on black shale protoliths from this period. [ABSTRACT FROM AUTHOR]

Samples of red bed sediments in several Mesoproterozoic successions contain enrichments of tellurium (Te), including discrete telluride minerals. The tellurides were neoformed during redox-controlled diagenesis, rather than representing mechanical concentrations of heavy minerals. Tellurium is enriched relative to selenium, which may reflect erosion of Archean and Palaeoproterozoic rocks with high Te contents. High continentality during the Mesoproterozoic would have limited the delivery of Te and other trace elements to the oceans, so accumulated Te on the continents. [ABSTRACT FROM AUTHOR]

Black sediment veins up to 2 cm width penetrate the Caledonian Helmsdale Granite in the vicinity of the Helmsdale Fault, onshore Moray Firth. The black colour and geochemistry of the veins reflect a high content of organic carbon. Both Devonian and Jurassic shales are conceivable available sources, but sterane compositions relate the organic matter to the Jurassic shales. A content of extractable organic matter higher than in the shales suggests that the carbon in the veins represents oil rather than mechanically mobilized shale. The oil was present during sediment vein emplacement. The veins were emplaced forcefully, which may reflect high fluid pressure associated with post-Jurassic movement on the Helmsdale Fault. [ABSTRACT FROM AUTHOR]

The Parys Mountain copper mining district (Anglesey, North Wales) hosts exposed pyritic bedrock, solid mine waste spoil heaps, and acid drainage (ochre sediment) deposits. Both natural and waste deposits show elevated trace element concentrations, including selenium (Se), at abundances of both economic and environmental consideration. Elevated concentrations of semi-metals such as Se in waste smelts highlight the potential for economic reserves in this and similar base metal mining sites. Selenium is sourced from the pyritic bedrock and concentrations are retained in red weathering smelt soils, but lost in bedrock-weathered soils and clays. Selenium correlates with Te, Au, Bi, Cd, Hg, Pb, S, and Sb across bedrock and weathered deposits. Man-made mine waste deposits show enrichment of As, Bi, Cu, Sb, and Te, with Fe oxide-rich smelt materials containing high Pb, up to 1.5 wt %, and Au contents, up to 1.2 ppm. The trace elements As, Co, Cu, and Pb are retained from bedrock to all sediments, including high Cu content in Fe oxide-rich ochre sediments. The high abundance and mobility of trace elements in sediments and waters should be considered as potential pollutants to the area, and also as a source for economic reserves of previously extracted and new strategic commodities. [ABSTRACT FROM AUTHOR]

The literature on community-based environmental management is very extensive and the discussion of the pros and cons is continuing. Presented here is an example of a successful interaction between university-based entomologists and a local rural community, detailing the change in the attitude of the town of Millbank, Jamaica, from a Giant Swallowtail Butterfly collecting site to a model for community protection of a species and its environment. A review of some of the research work on community-based conservation efforts is included. These linkages take a considerable time to establish and the efforts spent by scientific personnel, governmental representatives and eco-tourists are itemized to emphasize how specific conservation activities have inspired confidence in the local community, thus engendering trust and mutual respect between the two groups. Reviews of the developed legislative support from both international and state entities also must be in place, and these are included in chronological detail as much as possible. Finally, a review of the long-term funding of educational and other local programs providing a level of stability to the conservation effort, until the local community can take over the protection of the species and/or habitat, is provided. Of utmost importance is a comprehensive educational campaign to not only sensitize the community, but the larger society, so that there can be buy-in from all stakeholders. [ABSTRACT FROM AUTHOR]

Sandstone uranium (U) roll-front deposits of Wyoming and Colorado (USA) are important U resources, and may provide a terrestrial source for critical accessory elements, such as selenium (Se), molybdenum (Mo), and tellurium (Te). Due to their associated toxicity, Mo Se Te occurrences in roll-fronts should also be carefully monitored during U leaching and ore processing. While elevated Mo Se concentrations in roll-fronts are well established, very little is known about Te occurrence in such deposits. This study aims to establish Mo Se Te concentrations in Wyoming and Colorado roll-fronts, and assess the significance of these deposits in an environmental and mineral exploration context. Sampled roll-front deposits, produced by oxidized groundwater transportation through a sandstone, show high Mo Se content in specific redox zones, and low Te, relative to crustal means. High Se concentrations (up to 168 ppm) are restricted to a narrow band of alteration at the redox front. High Mo content (up to 115 ppm) is typically associated with the reduced mineralized nose and seepage zones of the roll-front, ahead of the U orebody. Elevated trace element concentrations are likely sourced from proximal granitic intrusions, tuffaceous deposits, and local pyritic mudstones. Elevated Mo Se content in the sampled roll fronts may be regarded as a contaminant in U in-situ recovery and leaching processing, and may pose an environmental threat in groundwaters and soils, so extraction should be carefully monitored. The identification of peak concentrations of Mo Se can also act as a pathfinder for the redox front of a roll-front, and help to isolate the U orebody, particularly in the absence of gamma signatures. [ABSTRACT FROM AUTHOR]

A suite of Permian sylvite samples from Boulby potash mine, Yorkshire, UK, consistently yield traces of hydrogen upon analysis by a cold crush technique for liberating volatiles from entrapped fluid inclusions. In contrast, accompanying halite samples do not yield hydrogen. These data suggest the formation of hydrogen by radiolysis of water due to irradiation from potassium in the sylvite. The data indicate radiolysis as a mechanism for subsurface hydrogen generation, where it is available as an electron donor for a deep biosphere. [ABSTRACT FROM AUTHOR]

Fluorine (F) plays an important role in biology and geology but is hard to analyse and quantify using element-specific techniques. This is related to its high first ionisation potential and analytical methods depending on high energy sources for excitation and/or ionisation of F. In particular ICP-MS was initially found incapable of detecting F; however, recent methodological advances, i.e., the application of Ba as a plasma modifier and the application of tandem mass spectrometry, enabled its analysis by targeting BaF+. In this study, we suggest this approach in conjunction with laser ablation to perform the mapping of F in both biological and geological samples. In a proof of concept, tooth samples as biological samples and a Rhynie chert as a geological sample were analysed. For method development and to evaluate the performance of the developed method, gelatine-based F-standards were prepared and characterised using combustion ion chromatography. Standards were further interrogated to estimate LODs and LOQs. Depending on the required spatial resolution, figures of merit in the upper ng g−1 range and lower μg g−1 range were achievable. This is the first example of F mapping using LA-ICP-MS instrumentation and the developed methods close an important analytical gap by enabling the spatially resolved F analysis at relevant biological and geological concentrations. [ABSTRACT FROM AUTHOR]

Phyllanthus kaweesakii Pornp., Chantar. & J.Parn. sp. nov. is newly described from the limestone mountain ridges in the northeast of Thailand. Comparison of morphology, anatomy, pollen morphology, and DNA sequences of this species with the most similar existing species P. mirabilis Müll.Arg. was undertaken. The results indicated that the two taxa are different in morphology, especially habit, stem base, and inflorescence, but that their pollen morphology and anatomy are similar. The molecular phylogenetic analysis, based on sequences of the plastid matK and nuclear ribosomal ITS regions, supported separation of the two taxa. This new species is described and illustrated, and its conservation status is discussed. [ABSTRACT FROM AUTHOR]

Background: Hydrogen is known to occur in the groundwaters of some ancient cratons. Where associated gases have been dated, their age extends up to a billion years, and the hydrogen is assumed also to be very old. These observations are interpreted to represent the radiolysis of water and hydration reactions and migration of hydrogen into fracture systems. A hitherto untested implication is that the overwhelming bulk of the ancient low-permeability basement, which is not adjacent to cross-cutting fractures, constitutes a reservoir for hydrogen. Results: New data obtained from cold crushing to liberate volatiles from fluid inclusions confirm that granites and gneiss of Archean and Palaeoproterozoic (>1600 Ma) age typically contain an order of magnitude greater hydrogen in their entrained fluid than very young (<200 Ma) granites. Sedimentary rocks containing clasts of old basement also include a greater proportion of hydrogen than the young granites. Conclusions: The data support the case for a global reservoir of hydrogen in both the ancient basement and in the extensive derived sediments. These reservoirs are susceptible to the release of hydrogen through a variety of mechanisms, including deformation, attrition to reduce grain size and diagenetic alteration, thereby contributing to the hydrogen required by chemolithoautotrophs in the deep biosphere. [ABSTRACT FROM AUTHOR]

The oxidation of molecular hydrogen (H2) is thought to be a major source of metabolic energy for life in the deep subsurface on Earth, and it could likewise support any extant biosphere on Mars, where stable habitable environments are probably limited to the subsurface. Faulting and fracturing may stimulate the supply of H2 from several sources. We report the H2 content of fluids present in terrestrial rocks formed by brittle fracturing on fault planes (pseudotachylites and cataclasites), along with protolith control samples. The fluids are dominated by water and include H2 at abundances sufficient to support hydrogenotrophicmicroorganisms, with strong H2 enrichments in the pseudotachylites compared to the controls. Weaker and less consistent H2 enrichments are observed in the cataclasites, which represent less intense seismic friction than the pseudotachylites. The enrichments agree quantitatively with previous experimental measurements of frictionally driven H2 formation during rock fracturing. We find that conservative estimates of current martian global seismicity predict episodic H2 generation by Marsquakes in quantities useful to hydrogenotrophs over a range of scales and recurrence times. On both Earth andMars, secondary release of H2 may also accompany the breakdown of ancient fault rocks, which are particularly abundant in the pervasively fractured martian crust. This study strengthens the case for the astrobiological investigation of ancient martian fracture systems. [ABSTRACT FROM AUTHOR]

There is very little understanding of tellurium (Te) distribution and behaviour in sedimentary rocks. A suite of 15 samples of reduction spheroids (centimetre-scale pale spheroids in otherwise red rock), including samples from eight localities in Triassic red beds across the British Isles, were mapped for Te using Laser Ablation-Inductively Coupled Plasma-Mass Spectrometry. Almost all showed enrichment in Te in the cores of the spheroids relative to background red bed concentrations, by up to four orders of magnitude. Some were also enriched over background in gold and/or mercury. In one case, discrete telluride minerals were recorded. The data show that Te is mobile and can be concentrated in low-temperature sedimentary environments, controlled by redox variations. The consistency in enrichment across widely separate localities implies that the enrichment is a normal aspect of red bed diagenesis and so likely to be controlled by a ubiquitous process, such as microbial activity. [ABSTRACT FROM AUTHOR]

Granites aged 1.9 Ga to 1.5 Ga exhibit molybdenite mineralization globally. Sandstones deposited during the mid-Proterozoic have a provenance dominated by 1.9–1.7 Ga basement. The mid-Proterozoic surface environment was, consequently, receiving detritus from the molybdenum-rich granites. Thus there was a supply of molybdenum available in terrestrial or shallow marine environments at a time when molybdenum was required to support the evolution of multicellular life. [ABSTRACT FROM AUTHOR]

The genus Dendromyza (Amphorogynaceae) comprises approximately 21 species with a distribution from the Malay Archipelago to southern Australia. Two new hemiparasitic species in this genus: D. hiepkoana from Irian Jaya and D. staufferi from Papua New Guinea are here described, illustrated and compared. Dendromyza hiepkoiana is similar to members of the genus Phacellaria (Benth.) where the leaves are very small and bract-like, but differs in its separate stigmas and chambered fruits that possess a crown of fibers on the endocarp. Dendromyza staufferi is allied to D. reinwardtiana (Bl. ex Korth.) Danser but differs from this species by broader, ovate rather than narrower, spathulate leaves and sessile inflorescences. Dendromyza staufferi also has an ovoid rather than elliptical endocarp and the crown of fibres at the apex of the endocarp are pilose. Due to their hemiparasitic nature and aerial habitat, species of Dendromyza are generally considered to be vulnerable in terms of conservation status. Based on the information available to us, however, the species described here are categorised as locally common or near threatened. [ABSTRACT FROM AUTHOR]

The Carboniferous Bowland Shale in England, and its correlatives in Ireland, contain anomalously high concentrations of trace elements, including selenium (Se), molybdenum (Mo) and arsenic (As). High levels of these elements reflect high sulphur contents as these elements occur as trace constituents of pyrite. Anomalous Se in particular may have a volcanic provenance, from contemporary volcanic activity and/or drainage from Ordovician volcanogenic sulphide deposits. Following concern over the release of Se and As into groundwater during shale gas extraction in the US, the potential fate of Se and As during any future shale gas extraction from the Bowland Shale merits attention. It is at least an environmental issue that must be managed, but at best it could be an opportunity for extraction of Se in an environmentally sensitive manner. [ABSTRACT FROM AUTHOR]

Oxidation on Mars is primarily caused by the high influx of cosmic and solar radiation which interacts with the Martian surface. The evidence of this can be seen in the ubiquitous red colouration of the Martian sediment. This radiation will destroy most signals of life in the top few metres of the Martian surface. If organic carbon (one of the building blocks of life) is present within the accessible Martian sediments, it is very likely that it will have experienced some oxidation. ESA׳s ExoMars mission set to fly in 2018, has on board a miniaturised Raman spectrometer. As Raman spectroscopy is sensitive to carbonaceous material and will be primarily used to characterise organics, it is essential that the effect oxidation has on the Raman carbon signal is assessed. Oxidised carbonaceous shales were analysed using Raman spectroscopy to assess this issue. Results show that haematite has a band which occurs in the same frequency as the carbon D band, which cannot be distinguished from each other. This can lead to a misidentification of the carbon D band and a misinterpretation of the carbon order. Consequently, caution must be taken when applying Raman spectroscopy for organic carbon analysis in oxidised terrestrial and extraterrestrial environments, including on Mars. [ABSTRACT FROM AUTHOR]

Selenium and tellurium are vital elements for the ongoing development of carbon-free energy generation, but are only recovered in small volumes as by-products of base and precious metal processing. Security of supply of these commodities is of high importance as their demand is forecast to increase in the near future, thus more research is required on the varying mineralization systems where their occurrence and behavior are poorly understood, such as sedimentary basins and metasedimentary terranes. The Munster Basin of southern Ireland is a good study area for sedimentary Se–Te in such environments as it has a regionally-high soil selenium anomaly, and is characterized by Devonian terrestrial red beds, which were metamorphosed during the Hercynian (Variscan) Orogeny. The area also contains ore-grade biogenic sediment-hosted copper and remobilized vein-hosted copper sulfides, which are prospective for chalcophile selenium and tellurium. Quartz vein-hosted Se–Te mineralization was identified across the Munster Basin, accompanied by trace gold–silver–mercury accessory phases. New sulfur isotope data reinforces the model of sulfur and selenium remobilized from a biogenic red bed source, which reflects a wider association of selenium deposits with oxidizing environments. The co-occurrence of tellurium mineralization suggests that it too may be concentrated in oxidizing environments. Associated traces of gold add to a growing body of evidence that gold is also transported and precipitated in oxidizing conditions in continental basins. [ABSTRACT FROM AUTHOR]

This study addresses the link between management concern for organizational crises and competitive strategy in small and medium-sized enterprises in Peru, Mexico and the United States. Surveys were completed by 270 Peruvian, 218 Mexican and 256 American managers. Strategic orientation in Peru did not mirror the broad pattern found in Mexico and in the United States. Levels of concern for crises were significantly higher in both Mexico and Peru than in the United States for 12 of 21 crises. The level of concern for crises tended to increase with management level more in Mexico and Peru than in the United States. Correlations between competitive strategy and crisis concern were significant in 26 of 126 instances. [ABSTRACT FROM AUTHOR]

Paleogeographic studies have shown that Earth was covered with more water during the Cretaceous than it is today, as the global sea level was significantly higher. The Cretaceous witnessed one of the greatest marine transgressions in Earth's history, represented by widespread deposition of sands directly on underlying basement. These sand bodies hold much of the world's heavy oil. Here, we present for the first time, geochemical evidence of a Cretaceous oil sand (Bima oil sand) in the Chad Basin, Nigeria. Bima oil sand is similar to other Cretaceous oil sands, predominantly occurring at shallow depths on basin flanks and generally lacking a seal cover, making the oil susceptible to biodegradation. The bulk properties and distribution of molecular features in oils from the Bima oil sand suggest that they are biodegraded. Sterane maturity parameters and the trisnorhopane thermal indicator for the oils suggest thermal maturities consistent with oils generated as conventional light oils, which later degraded into heavy oils. These oils also show no evidence of 25-norhopane, strongly suggesting that biodegradation occurred at shallow depths, consistent with the shallow depth of occurrence of the Bima Formation at the study locality. Low diasterane/sterane ratios and C 29 H/C 30 H ratios greater than 1 suggest a carbonate source rock for the studied oil. The Sterane distribution further suggests that the oils were sourced from marine carbonate rocks. The C 32 homohopane isomerization ratios for the Bima oil sand are 0.59–0.60, implying that the source rock has surpassed the main oil generation phase, consistent with burial depths of the Fika and Gongila Formations, which are both possible petroleum source rocks in the basin. [ABSTRACT FROM AUTHOR]

This empirical analysis of hotel properties in south-western Turkey draws on the market orientation, strategy, and capabilities literature to highlight the benefits of a differentiation strategy and customer-value focus for competitors in this industry. Relationship management and organizational resource management are key drivers of sales growth in this industry, and hotel operators facing high competitive intensity are particularly encouraged to develop these capabilities and to adopt a differentiation strategy instead of resorting to price cutting and other pricing and promotional tactics to grow revenues. Notable opportunities for future research include examining relationships between market orientation, customer satisfaction, and employee satisfaction in the Turkish hotel industry. [ABSTRACT FROM PUBLISHER]

There is extensive evidence for the microbial colonization of seafloor basalts in the modern ocean and in the geological record. The sulfur isotope composition of pyrite in the basalts commonly indicates marked isotopic fractionation due to microbial sulfate reduction. Sections through the Nemagraptus gracilis zone (Ordovician) in Great Britain and Ireland are characterized by both widespread pillow lavas and organic-rich seafloor sediment, allowing an exceptional opportunity to assess whether the availability of organic carbon influenced the extent of microbial activity in the basalts in deep geological time. Whole-rock data from basalts at 10 localities show that there is a relationship between sulfur isotopic composition and the carbon content of the basalt. At two localities where organic carbon was entrained in the basalt, isotopic compositions are heavy compared to compositions in carbon-poor basalt, implying that microbial activity exhausted the supply of seawater sulfate. In most basalt, microbial activity was limited by the supply of carbon, but where the basalt incorporated carbon during emplacement on the seafloor, microbial activity became sulfate limited. [ABSTRACT FROM AUTHOR]

Pyrite is consistently found in modern seafloor vesicular basalts and has a sulphur isotopic composition consistent with microbial activity. We present S isotope data from pyrite in Ordovician pillow lavas at localities across the British Isles, which yield a range of δ34S compositions consistent with two components of sulphur: groundmass pyrite (~0 ± 4‰) and 32S-enriched pyrite in the vesicles (−8‰ to −27‰). The latter are recorded from vesicular lavas in four different terranes, representing different settings at the margins of the Iapetus Ocean. Whereas a component of magmatic sulphate is recognized in the groundmass values, the isotopically light data in the vesicles are consistent with microbial reduction of seawater sulphate in sub-seafloor lavas. This is consistent with modern examples and indicates considerable longevity for this sub-seafloor microbial habitat. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

[Display omitted] • Coupled vanadium-carbonaceous deposits were particularly developed during a 200 Myr period from the Cryogenian to Cambrian. • Vanadium became available to the surface during the Neoproterozoic when anomalously high levels were introduced in large igneous provinces. • Global glacial erosion transported continental vanadium to the oceans, together with trace elements that caused high productivity and organic carbon accumulation. • The combination of vanadium and organic carbon gave rise to a range of deposits, which provide a model to support exploration for further resources. The anticipated high demand for new vanadium resources in support of the green energy revolution will be partly met by vanadium in carbonaceous deposits. This type of deposit is particularly developed during a 200 Myr period from Cryogenian-Cambrian. During this period, anoxic conditions were widely developed and provided a template for vanadium deposition. Vanadium became available to the surface during the Neoproterozoic when anomalously high levels were introduced in large igneous provinces. Global glacial erosion transported vanadium to the oceans, along with trace elements that engendered organic carbon accumulation. The combination of vanadium and organic carbon gave rise to a range of deposits, and provides a model to support exploration for further resources. [ABSTRACT FROM AUTHOR]

Analysis of oil samples from the Niger Delta (Nigeria) revealed a range of structurally related hopanes, including 25-norhopanes, and hopanoic and 25-norhopanoic acids. 25-Norhopanes were detected in all medium and heavily biodegraded oils and were most abundant in the heavily degraded oils. Hopanoic acids (C 30 -C 33 ) and 25-norhopanoic acids (C 30 -C 31 ) were most abundant in moderately degraded oils and occurred in reduced concentration in heavily degraded oils but were absent from, or in trace concentration in, slightly degraded oils. Consideration of the structures suggests that 25-norhopanoic acids form via carboxylation of 25-norhopanes or demethylation of hopanoic acids. Mass balance for the onshore Niger Delta oils suggests that formation of 25-norhopanes operates independently of 25-norhopanoic acid formation and that 25-norhopanoic acids are likely transient intermediates for only a small proportion of the 25-norhopanes. [ABSTRACT FROM AUTHOR]

The exploration for selenium (Se) and tellurium (Te) will become intensified as the technological demand for these elements grows. It is known that they are enriched in organic-rich sedimentary rocks over crustal mean values. LA-ICP-MS measurement of pyrite in two biodegraded palaeo-oil reservoirs in central England shows that Se and Te are enriched in them, but not in other sulfide samples from the region and elsewhere. The Carboniferous source rock shales in the region are Se-rich, implying that this enrichment was conferred to the oil generated from them. The Se and Te are located in pyrite precipitated in the palaeo-reservoirs by microbial activity. Exhumed oil reservoirs merit further investigation for concentrations of these elements. [ABSTRACT FROM AUTHOR]

The burial of organic carbon in sedimentary systems has been a fundamental part of the carbon cycle throughout the geological record, and was instrumental in major oxygenations of the atmosphere in the early Palaeoproterozoic and Neoproterozoic. While much focus has been placed on the burial of carbon in Precambrian marine carbonate and organic carbon-rich rocks deposited around the time of these major oxygenations, such deposits yield little information on the evolution of the atmosphere in the significant time between. There is, however, growing evidence from terrestrially deposited sediments to suggest the surface environment may have been at least intermittently well-oxygenated from the late Mesoproterozoic. Hence Proterozoic sediments deposited in terrestrial near-surface environments are useful targets for the study of atmospheric evolution during a time which is hitherto poorly understood. Thus far, little attention has been paid to the contribution of large lakes and intercontinental basins to the global burial of organic carbon, and thus the progressive oxygenation of the atmosphere, especially given that the highest rates of organic carbon burial in modern aquatic environments occur in lacustrine settings, in stark contrast to the low rates observed in the contemporary marine realm. Here, we report high burial rates of organic carbon in large lacustrine systems of late Mesoproterozoic to early Neoproterozoic age, which are comparable with modern lacustrine systems, and significantly higher than modern and ancient marine deposits. These data emphasise the significance of lakes as a global repository for organic carbon, and imply Proterozoic lakes were at least as efficient, and perhaps as important, as modern lakes in the global burial of organic carbon. Such findings suggest large Proterozoic lakes and epicontinental basins played a crucial role in the progressive oxygenation of the atmosphere before the major Neoproterozoic oxygenation. [ABSTRACT FROM AUTHOR]

The ESA/Roscosmos ExoMars rover will be launched in 2018. The primary aim of the mission will be to find evidence of extinct or extant life by extracting samples from the subsurface of Mars. The rover will incorporate a drill that is capable of extracting cores from depths of up to 2 m, a Sample Preparation and Distribution System (SPDS) that will crush the core into small grains and a suite of analytical instruments. A key component of the analytical suite will be the Raman Laser Spectrometer (RLS) that will be used to probe the molecular and mineralogical composition of the samples. In this work we consider the capability of the proposed Raman spectrometer to detect reduced carbon (possibly associated with evidence for extinct life) and to identify the level of thermal alteration/maturity. The Raman analysis of 21 natural samples of shale (originating from regions exhibiting different levels of thermal maturity) is described and it is shown that reduced carbon levels as low as 0.08% can be readily detected. It is also demonstrated that the Raman spectra obtained with the instrument can be used to distinguish between samples exhibiting high and low levels of thermal maturity and that reduced carbon can be detected in samples exposed to significant levels of oxidation (as expected on the surface of Mars). [ABSTRACT FROM AUTHOR]

Lamina by lamina measurement of biomarkers at a sub-millimetre resolution within the Achanarras Limestone Member has helped to resolve the changing environmental conditions associated with a fish mass mortality horizon. An anomalous proportion of C 30 sterane (24- n -propylcholestane) marks the beginning of the horizon and likely corresponds to an influx of marine water. This appears to have been short lived and was likely analogous to a modern day storm tide. The subsequent laminae record an increased incidence of water column stratification and hypoxic bottom waters in the form of an elevated gammacerane index. The mass mortality horizon studied was from an upper interval of the Achanarras Limestone Member with a fossil fish assemblage comprising mostly Dipterus , an early Dipnoan (lungfish). However, lower intervals of the Achanarras Limestone Member have greater assemblage diversity, including species associated with marine conditions such as Coccosteus , and evidence higher proportions of C 30 sterane indicating better connection to the marine environment. Therefore, it appears that ingressing seawater in and of itself was not responsible for creating a stressed environment. Rather, disconnection of the lake from marine waters stranded fish in a lake, that when perturbed by storm tides, killed en masse by exposing fish to hypoxic conditions in a similar way to modern water bodies affected by storm tides generated during hurricanes. [ABSTRACT FROM AUTHOR]