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Halogenated inorganic complexes Ax[MHaly] (A = alkali metal or alkaline earth, M = transition or main group metal, x = 1–3, and y = 2–9) are an archetypal class of compounds that provide entry points to large areas of inorganic and physical chemistry. All of the hexahalo complexes adopt an octahedral, Oh, symmetry (or nearly so). Consequently, one of the bending modes is forbidden in both the infrared and Raman spectra. In the solid state, many of the complexes crystallize in the cubic space group Fm3̅m, which preserves the octahedral symmetry. Even for those that are not cubic, the octahedral symmetry of the [MHal6]n− ion is largely retained and, to a good approximation, so are the selection rules. In the present work, we show that by using the additional information provided by neutron vibrational spectroscopy, in combination with conventional optical spectroscopies, we can generate complete and unambiguous assignments for all the modes. Comparison of the experimental and calculated transition energies for the systems where periodic-density functional theory was possible (i.e., those for which the crystal structure is known) shows that the agreement is almost quantitative. We also provide a linear relationship that enables the prediction of the forbidden mode.

Prediction of sandstone body dimensions within paralic depositional systems is crucial for the development of predictive 3D reservoir models. Continental-scale paralic reservoir targets have complex architectures, with interpretation often further compounded because they are often located at subsurface depths ≥2 km in pre- and synrift basinal settings, typified by poor seismic resolution. As such, in many cases analysis relies on core and wireline-log data, from which depositional facies are interpreted and thicknesses of sandstone reservoir units measured. Estimation of width:thickness (W:T) ratios for different reservoir elements relies on analogue data. However, the inherent uncertainty in the initial interpretation of core/log data and the wide W:T ranges for different sandstone bodies within published analogue datasets hinders prediction of accurate reservoir geometry/dimensions. Without access to quality seismic data, constraining the evolution and dimensions of reservoirs in these depositional systems is challenging.This paper presents a detailed case study of the Triassic Mungaroo Formation, and assesses the uncertainty and limitation of interpretations that can be made about reservoir architecture and the evolution of a paralic depositional system, if only wireline and core data are available.The Mungaroo Formation is characterized by upper and lower delta-plain channel sandstones, swamps and restricted embayments, through to delta-front and pro-delta heterolithics. Core-to-wireline-log calibration allowed identification of key marine intervals that enabled well correlations to be established across the study area, based on candidate flooding surfaces. Applying classic sequence stratigraphic models to low gradient fluvio-deltaic systems is difficult, due to a lack of preservation and/or confident identification of laterally continuous chronostratigraphic markers. The large-scale temporal change in reservoir architecture was likely to have been controlled by eustatic sea level causing overall transgression of the depositional system. However, the observed complex spatial facies variability is most likely controlled by climatic-induced changes in sediment supply/fluvial discharge and autocyclic processes.Four classes of sandstone bodies/reservoir elements have been identified from core and wireline data based on their thickness distributions. Whereas core to wireline to seismic calibration has enabled large-, medium- and small-scale geobodies to be identified representing fluvial channel belt complexes; multistorey channel belts; and single-storey channel belts, respectively. To predict channel body widths and sinuosity from thickness data extracted from wells, typically, analogue data are used. However, for each geobody type there is a large range of possible sandstone body dimensions based on published literature. The largest-scale sand bodies, with most significance as reservoir targets, have possible interpretations as either incised valleys or amalgamated channel belts, based on their thickness ranges alone. This poses significant uncertainty for understanding the evolution of the depositional system and input into predictive reservoir models.This study emphasizes the importance of understanding the range of uncertainty of interpretation and the need for refined analogue data to better constrain reservoir element dimensions when relying solely on well-log datasets. Where seismic attribute analysis from high-quality 3D seismic data are available, W:T dimensions for reservoir elements can be constrained more accurately and correlated to core and log data. The existing global database is limited, often poorly constrained due to the use of variable terminology and potential for misinterpretation. Many studies lack statistical rigour. We conclude that further high-resolution studies are required to build more robust and quantitative analogue datasets.

Post-drilling open-hole log measurements made by wireline tools are most commonly transmitted to surface via wireline, but the trend is towards increased use of memory-capable tools with greater operational flexibility. The primary purpose of the original memory tools was to operate on wireline in intermediate and TD sections while offering a low-risk alternative to conventional tools in horizontal wells, bad hole conditions and other challenging well scenarios. This wide operational envelope required the tools to be small-diameter to allow protected conveyance inside drill pipe, but it also required that measurement performance and associated environmental characterization be on a par with conventionally sized tools that generated the majority of the historical record. The extent to which these goals have been achieved, using evidence from the over 150,000 wells logged with the most highly developed of the small-diameter tool types, is reviewed. Standard response modelling is essential but insufficient to ensure optimum measurement performance. Findings from the performance in thousands of wells have been used to refine models, hardware designs and processing algorithms, including more precise control on the position of tools in the wellbore. Log data from test wells and commercial wells are provided showing the measurement quality from small-diameter tools matches that from conventionally sized tools for the large majority of operations. Log data is also provided from wells that had presented insurmountable challenges for traditional logging tools which demonstrate the conveyance flexibility and the reduced acquisition risk in using the small-diameter tools. The significance of the findings is that the performance of the most highly developed small-diameter tools has evolved to the point where measurement quality is not a differentiating factor for the large majority of operations, allowing job planning to be driven by the other considerations, in particular the minimization of acquisition risk.

The genetics of reproduction is poorly understood because the heritabilities of traits currently recorded are low. To elucidate the genetics underlying reproduction in beef cattle, we performed a genome-wide association study using the bovine SNP50 chip in 2 tropically adapted beef cattle breeds, Brahman and Tropical Composite. Here we present the results for 3 female reproduction traits: 1) age at puberty, defined as age in days at first observed corpus luteum (CL) after frequent ovarian ultrasound scans (AGECL); 2) the postpartum anestrous interval, measured as the number of days from calving to first ovulation postpartum (first rebreeding interval, PPAI); and 3) the occurrence of the first postpartum ovulation before weaning in the first rebreeding period (PW), defined from PPAI. In addition, correlated traits such as BW, height, serum IGF1 concentration, condition score, and fatness were also examined. In the Brahman and Tropical Composite cattle, 169 [false positive rate (FPR) = 0.262] and 84 (FPR = 0.581) SNP, respectively, were significant (P < 0.001) for AGECL. In Brahman, 41% of these significant markers mapped to a single chromosomal region on BTA14. In Tropical Composites, 16% of these significant markers were located on BTA5. For PPAI, 66 (FPR = 0.67) and 113 (FPR = 0.432) SNP were significant (P < 0.001) in Brahman and Tropical Composite, respectively, whereas for PW, 68 (FPR = 0.64) and 113 (FPR = 0.432) SNP were significant (P < 0.01). In Tropical Composites, the largest concentration of PPAI markers were located on BTA5 [19% (PPAI) and 23% (PW)], and BTA16 [17% (PPAI) and 18% (PW)]. In Brahman cattle, the largest concentration of markers for postpartum anestrus was located on BTA3 (14% for PPAI and PW) and BTA14 (17% PPAI). Very few of the significant markers for female reproduction traits for the Brahman and Tropical Composite breeds were located in the same chromosomal regions. However, fatness and BW traits as well as serum IGF1 concentration were found to be associated with similar genome regions within and between breeds. Clusters of SNP associated with multiple traits were located on BTA14 in Brahman and BTA5 in Tropical Composites.

Earlier it was observed that polarization rotation in an AWG built from birefringent waveguides can result in sidelobes in its response. This effect was measured in a polarization sensitive AWG with an orthogonal layout. Now we investigate through detailed simulation whether this effect also exists in polarization desensitised AWGs. It is shown that a dispersion compensated AWG does not suffer from a polarization sidelobe. Alternatively, the AWG can be designed to minimize polarization rotation to suppress the sidelobe.

This paper proposes a model for glaciation in Oman during the late Palaeozoic ice age (LPIA) based on sedimentological and provenance analyses of the Late Carboniferous- Early Permian Al Khlata Formation, exposed in the Huqf, Oman. The results demonstrate a complex pattern of glaciation across Oman, not fully recognized in previous models. Striated glacial pave- ments provide evidence for two phases of ice advance: a phase of ice sheet advance towards the NE, and a second and probably younger phase where an ice centre localized on the Huqf High flowed towards the SW. The stratigraphy is constrained by previous palynological studies and is sub- divided into three units, from oldest to youngest: 'early' AKP5, 'late' AKP5 and AKP5/P1. 'Early' AKP5 palaeogeography is characterized by ice-contact glacial lacustrine and deltaic sedi- mentary environments along the western margin of the Huqf High. Meltwater discharge flowed into the lake from ice margins located to the east, upon the Huqf High, recorded by progradational delta and fan complexes. 'Late' AKP5 palaeogeography is characterized by pro-glacial fluvial- deltaic outwash braidplains that record high-magnitude meltwater discharge from an ice margin located to the SW of the study area. The youngest undifferentiated AKP5/P1 palaeogeography is characterized by re-establishment of ice-contact glaciolacustrine conditions.

Trace fossils from the Middle Devonian Caherbla Group of the Dingle Peninsula, southwest Ireland, record a diverse arthropod fauna inhabiting a hot-arid intracontinental rift setting. Aeolian dunefield and coeval fluvial interdune deposits interfinger spatially and temporally with alluvial fan sedimentary rocks. Three distinct trace fossil assemblages are recognized. The Taenidium-Scoyenia ichnocoenosis occurs in alluvial fan and fluvial channel deposits, and includes the large backfilled burrow Taenidium, interpreted as eoarthropleurid aestivation chambers. The Rusophycus-Protichnites ichnocoenosis, composed of arthropod trackways and surface pits, occurs in an interdune ponded area that was susceptible to ephemeral fluvial flow, with Rusophycus showing preferred orientation into the oncoming palaeocurrent. Both the Taenidium-Scoyenia and Rusophycus-Protichnites ichnocoenoses are assignable to the globally recurring continental Scoyenia ichnofacies. They are clearly substrate-controlled and moisture-related due to the ephemeral nature of the fluvial system. The Palmichnium-Entradichnus ichnocoenosis occurs in aeolian dune deposits, and includes Palmichnium, attributed to large stylonurid eurypterids, and Diplichnites, attributed to eoarthropleurids. These trackways represent the activities of dune pioneers that left their fluvial habitat to forage for detritus. Interface burrows (Entradichnus, Palaeophycus) were also constructed by arthropods moving just under the sand surface and vertical burrows (Cylindricum, Pustulichnus) were made by arthropods digging downward. Trace preservation in the aeolian environment was probably enhanced by heavy nocturnal dew-fall or light rain. The Palmichnium-Entradichnus ichnocoenosis is assigned to the globally recurring aeolian Octopodichnus-Entradichnus ichnofacies. This aeolian facies, and associated ichnofauna described herein, represents the oldest development of a unique erg system in the Old Red Sandstone (Devonian) of the southern British Isles, and one of the oldest and most diverse aeolian ichnofaunas to be reported worldwide. Copyright © 2011 John Wiley & Sons, Ltd.

This article considers the history of the transmission of the opening verses of the Fourth Gospel and the ways in which the text was divided or not divided into segments by commentators (e.g. Ptolemy, Heracleon, Irenaeus, Cyprian, Chrysostom, Augustine, Cyril, Philoxenus), liturgical systems and the scribes of early manuscripts (e.g. Arabic, Armenian, Coptic, Ethiopic, Georgian, Greek, Latin, Syriac). There is then investigation of the division of the text in the period of print from 1495 (the first printing of Jn 1.1-14) to the present. It is found that systems that regarded Jn 1.1-5, 1-14, or 1-17 as a unit preceded those that regarded 1.1-18 as a unit and that these earlier analyses each have distinct exegetical advantages over the common modern position of viewing 1.1-18 as a unit. The reasons for the currently preferred division and its exegetical consequences are explored with the conclusion that Jn 1.1-18 should not be regarded as the prologue of the Fourth Gospel.

Permo-Triassic rift basins offer important hydrocarbon targets along the Atlantic margins. Their fill is dominated by continental red beds, comprising braided fluvial, alluvial fan, aeolian, floodplain and lacustrine facies. These relatively lightly explored basins span both the Atlantic and Tethyan domains and developed above a complex basement with inherited structural fabrics. Sparse data in offshore regions constrain understanding of depositional geometries and sedimentary architecture, further impeded by their deep burial beneath younger strata, combined with the effects of later deformation during continental breakup. This paper provides results from a multidisciplinary analysis of basins along the Atlantic margin. Regional seismic and well data, combined with geochemical provenance analysis from the European North Atlantic margins, are integrated with detailed outcrop studies in Morocco and Nova Scotia. The research provides new insights into regional basin tectonostratigraphic evolution, sediment fill, and reservoir distribution, architecture and quality at a range of scales. Regional seismic profiles, supported by key well data, indicate the presence of post-orogenic collapse basins, focused narrow rifts and low-magnitude multiple extensional depocentres. Significantly, Permo-Triassic basin geometries are different and more varied than the overlying Jurassic and younger basins. Provenance analysis using Pb isotopic composition of detrital K-feldspar yields new and robust controls on the sediment dispersal patterns of Triassic sandstones in the NE Atlantic margin. The evolving sedimentary architecture is characterized by detailed sedimentological studies of key outcrops of age equivalent Permian-Triassic rifts in Morocco and Nova Scotia. The interplay of tectonics and climate is observed to influence sedimentation, which has significant implications for reservoir distribution in analogue basins. New digital outcrop techniques are providing improved reservoir models, and identification of key marker horizons and sequence boundaries offers a potential subsurface correlation tool. Future work will address source and seal distribution within the potentially petroliferous basins.

Triassic dryland fluvial systems occur infilling extensional and post-rift basins across northwest Europe. These systems were deposited by streams draining off the major basin margin catchments of Greenland, Fennoscandia, the Scottish Highlands and the remnant Variscan mountains. Fluvial drainage was dominantly endorheic in character, and terminated in playa, aeolian dune, sabkha or marsh settings. Whilst the ambient basin climate fluctuated through varying levels of aridity and humidity, the dispersal of sand into these basins was critically dependant on catchment run-off from the major, basin flanking regions. In the Early Triassic the Tethyan monsoon drove seasonal precipitation over the Variscan mountains which transported sediment northward into arid dune fields and playa. In addition, far-travelled fluvial systems supplied sediment from distant, wetter catchments. Through the Middle and Late Triassic the effects of the Tethyan monsoon apparently weakened, and sand-prone fluvial systems draining off the Variscan mountains were more limited in areal extent, but expanded during pluvial episodes. However, Greenland and Fennoscandia maintained sediment supply from the north, with perennial run-off from Fennoscandia able to maintain marshes and levels of vegetation cover not encountered elsewhere in the region and to episodically drive major exorheic drainage systems into the Tethys Sea. Published climatic simulations are consistent with these observations, which indicate that Greenland, and particularly Fennoscandia, had precipitation levels higher than the regions to the south with a positive precipitation: evaporation balance. Copyright © 2009 John Wiley & Sons, Ltd.

Determining what the controls are on the large-scale (> 10 km) horizontal architecture of coarse-grained fluvial deposits is important for understanding subsurface fluid distribution and extraction from these important aquifers and hydrocarbon reservoirs. This contribution describes the architecture of coarse-grained fluvial sediments from an almost continuous lateral profile 27 km long by 115 m high in the Upper Triassic Wolfville Formation, (Fundy Basin, Nova Scotia). The lateral extent and quality of exposure allows development of a high-resolution correlation scheme and definition of architectural elements. The lower Wolfville Formation lithofacies, composed of breccias, conglomerates, sandstones, mudstones, and paleosols, comprises alluvial-fan, fluvial, and ephemeral lake-margin facies associations. Alluvial-fan deposits form 15% of the studied section and are developed locally between the overlying fluvial facies and the unconformity with Carboniferous strata, where they infill remnant topography. The succession is dominated (80%) by pebbly sandstones deposited as part of a gravelly braided fluvial system and ends abruptly with a thin ephemeral lake-margin facies association (5%). The large-scale architecture and sedimentology of the pebbly sandstone succession is documented with particular attention focussed on bounding surfaces and stacking patterns. In the fluvial facies association two scales of development of erosion surface and cycles can be recognized. The “S” surfaces can be correlated across the profile (> 27 km) and show evidence of up to 10 m of erosion, a significant facies or grain-size change, onlap, and association with mature calcic paleosols. The “E” surfaces can be correlated between 5 and 17 km, display erosion of The regional extent of the “E” and “S” surfaces indicate that the gravelly fluvial system has a large-scale, sheet-like geometry which comprises a series of stacked, erosion-dominated, multi-story bodies. High-resolution architectural elements are poorly defined in this coarse fluvial system and make it difficult to constrain the scale of the depositional system. An individual high-resolution cycle records braid-plain development and is interpreted as a multi-story channel belt. The braid-plain width is estimated at 19 km but the width of individual active channels is unknown. The sediments were deposited in a proximal fluvial setting disconnected from marine influences. We interpret the high-resolution cycles and bounding “E” surfaces to record a progressive decrease in runoff and fluvial transport capacity indicative of a drying-upward, climatically driven signal. The origin of the S-surface-bounded packages is more difficult to determine. A variety of mechanisms are considered, including changes in discharge driven by climatic fluctuations, changes in stream power related to drainage capture within the source area, and tectonic tilting. An important aspect of the study is that the “S” surfaces can be identified and correlated for > 27 km, and provide an example of a robust, high-resolution correlation framework in coarse-grained braided fluvial deposits that could be applied elsewhere. In contrast the “E” surfaces do not display any significant changes in facies or grain size across them, such that many of the smaller scale cycles could potentially be miscorrelated.

Green crab (Carcinus maenas) have recently invaded the southern Gulf of St. Lawrence, Canada. Although these invasive crabs have coexisted without appreciable impact on American lobster (Homarus americanus) populations in northeastern United States, Bay of Fundy, and the southern shore of Nova Scotia, Canada, the green crab in the southern Gulf of St. Lawrence likely represents a new introduction of crab from northern Europe. The southern gulf is ideal habitat for green crab, and the crab are commonly captured subtidally, increasing the potential for overlap with juvenile lobsters. To complement previous experiments with green crab versus small (28–57 mm carapace length, CL) and medium (55–70 mm CL) sized lobsters in food competition trials, this paper reports findings from trials with large (72–80 mm CL) lobsters. The lobsters were first to gain possession of the food in an equal number of trials as green crab. The large lobsters fed for 62% of the total feeding time, versus 38% for the green cr...

As a result of the advancing global technologies and civilisation, there has been a progressive depletion of high-grade mineral deposits. Consequently, it has become increasingly important to process lower-grade ores. Phosphorous (P) and particular potassium (K) contained in the iron ore concentrates of the Sishen Iron Ore Mine have a detrimental effect on the steel making process, whereby these alkali’s cause cracks to form in the refractory lining of blast furnaces. It is initially essential to determine which microbes are indigenously present at the Sishen Iron Ore Mine before strategising how best to employ them to industrial advantage. Therefore, the objective of this study was to determine which microorganisms are indigenous to the iron ore and soil of the Sishen Iron Ore Mine. The bacterial 16S PCR and fungal ITS PCR revealed several bacterial and fungal species present in the mine environment. The bacterial isolates were found to be closely related to Herbaspirillum species, as well as Acidithiobacillus ferrooxidans, while the fungal isolates were closely related to Aureobasidium pullulans, Phaeosphaeria nodorum, Aspergillus fumigatus, and Candida parapsilosis. Isolating A. fumigatus from the iron ore/soil of the mine may indicate that A. niger, the most common fungi used for the production of citric acid, can adapt to the stringent mine environment. This would allow the application of A. niger for the production of citric acid, which may be used for the chemical leaching of the P and K from the iron ore concentrate of the Sishen Iron Ore Mine.

The Early Devonian Conigar Pit Sandstone Member (CPSM) of the Freshwater West Formation (Lower Old Red Sandstone, Lochkovian age) at Freshwater West in south Wales comprises a heterolithic, predominantly alluvial suite (mudstones, fine to coarse-grained sandstones, conglomerates) with varying depositional architecture. A number of discrete facies associations are observed. The fine-grained, inclined- and non-inclined heterolithic association is dominant within the CPSM. It represents dryland sinuous channelized flow (IHS bedsets) and unconfined flow (non-inclined bedsets) at terminal and intermediate floodouts deposited under semi-arid conditions. Mudstones were deposited in two distinct environments associated with this semi-arid river system. Laminated and burrowed, reddish brown mudstones were deposited in shallow semi-permanent lakes or pools on the floodplain. Massive mudstones were deposited as within-channel muddy braid-bars, with sedimentary structures being lost during subsequent compaction. The mudstones exhibit Vertisol pedogenesis reflecting the seasonal wetting and drying associated with the semi-arid climate. Periods of intense desiccation are indicated by deep desiccation cracks and associated rubbly surfaces. Possible, though unproven tidal conditions influenced a small percentage of the heterolithic channels at Freshwater West. The extent of these channels is uncertain. The coarser-grained multi-storey sandstone association was deposited by low-sinuosity rivers with a fluctuating, but perennial discharge. Associated with these laterally extensive sandbodies was a high water table with surface ponding (wetlands) that enabled the preservation of plant detritus. During high discharge events, flow expanded over the contemporaneous floodplain depositing the sheet sandstone association within splay complexes. The interpretation that perennial discharge may have been triggered by basin-wide climate change challenges the long-held view that the Lower ORS climate was continuously semi-arid in nature. The spatial/temporal extent of this climate change is uncertain, as it is possible that the multi-storey sandbodies were deposited by allogenic rivers draining a distant, possibly uplifted source area. A decrease in the observed frequency and maturity of Vertisol profiles, and a corresponding increase in multi-storey sandbodies upward through the succession may reflect a long-term, episodic pattern of climate change.

The lower part of the Old Red Sandstone in the Dingle Penisula has been previously assigned to one lithostratigraphic group (Dingle Group) despite marked variations in sedimentary facies. However the apparently oldest non-marine sequence in the northwest of the peninsula has sedimentary and lithological attributes that contrast strongly with those of the late Silurian-early Devonian Dingle Group to the south. This northern sequence, here renamed the Smerwick Group, evolved independently of the Dingle Group in a separate basin of deposition. Field relationships between the two groups in the north of the peninsula are interpreted as indicating that the Smerwick Group overlies, with angular unconformity, a normal Dingle Group succession. Similarly, it is argued that the Smerwick Group overlies, with angular unconformity, the Dingle Group in the northwest of the peninsula, but there the Dingle Group is attenuated, represented only by a conglomerate unit some 10 m thick. In the absence of biostratigraphic evidence the age of the Smerwick Group is poorly constrained. Nevertheless, we propose a tectonic model that suggests that the Smerwick Group evolved within a small extensional half-graben on the northern margin of the Munster Basin. This model accounts for the stratigraphic and structural relationships observed, and implies that the Smerwick Group is of Late Devonian age.

Trace fossils of Beaconites type are found abundantly and widely in the Old Red Sandstone magnafacies of the British Isles, particularly in fluviatile deposits, where they occur in or closely associated with channel sandstones. Because of their giant size, however, terminations to the sediment-filled burrows are almost impossible to detect, and it has hitherto been uncertain whether the Beaconites organism dwelt in or near active rivers, or merely colonized the sandy deposits at their abandoned sites. At Llanstephan in southwest Wales B. antarcticus is preserved in a laterally accreted sandstone, a unique example of the trace fossil being truncated by an erosion surface cut during the sideways growth of a presumed point bar. The Beaconites organism is therefore thought to have lived in and near active river channels, where a moist environment was provided.