bluuebunny/crossref_metadata_2025 huggingface dataset:
A mixed solid‐shell element for the analysis of laminated composites
Authors: Rah K. , Van Paepegem W. , Habraken A. M. , Degrieck J.
Published: November 2011

This paper presents a versatile low order locking‐free mixed solid‐shell element that can be readily employed for a wide range of linear elastic structural analyses, that is, from thick isotropic structures to multilayer anisotropic composites. This solid‐shell element has eight nodes with only displacement degrees of freedom and few assumed stress parameters that provide very accurate interlaminar stress calculations through the element thickness. These elements can be stacked on top of each other to model multilayer structures, fulfilling the interlaminar stress continuity at the interlayer surfaces and zero traction conditions on the top and bottom surfaces of the laminate. The element formulation is based on the well‐known Fraeijs de Veubeke–Hu–Washizu mixed variational principle with enhanced assumed strains formulation and assumed natural strains formulation to alleviate the different types of locking phenomena in solid‐shell elements. The distinct feature of the present formulation is its ability to accurately calculate the interlaminar stress field in multilayer structures, which is achieved by the introduction of a constraint equation on the interlaminar stresses in the Fraeijs de Veubeke–Hu–Washizu principle‐based enhanced assumed strains formulation. The intelligent computer coding of the present formulation makes the present element appropriate for a wide range of structural analyses. To assess the present formulation's accuracy, a variety of popular numerical benchmark examples related to element convergence, mesh distortion, and shell and laminated composite analyses are investigated and the results are compared with those available in the literature. These benchmark examples reveal that the proposed formulation provides very good results for the structural analysis of shells and multilayer composites. Copyright © 2011 John Wiley & Sons, Ltd.
A framework for coupled deformation–diffusion analysis with application to degradation/healing
Authors: Mudunuru M.K. , Nakshatrala K.B.
Published: November 2011

This paper deals with the formulation and numerical implementation of a fully coupled continuum model for deformation–diffusion in linearized elastic solids. The mathematical model takes into account the effect of the deformation on the diffusion process, and the affect of the transport of an inert chemical species on the deformation of the solid. We then present a robust computational framework for solving the proposed mathematical model, which consists of coupled non‐linear partial differential equations. It should be noted that many popular numerical formulations may produce unphysical negative values for the concentration, particularly, when the diffusion process is anisotropic. The violation of the non‐negative constraint by these numerical formulations is not mere numerical noise. In the proposed computational framework, we employ a novel numerical formulation that will ensure that the concentration of the diffusant be always snon‐negative, which is one of the main contributions of this paper. Representative numerical examples are presented to show the robustness, convergence, and performance of the proposed computational framework. Another contribution of this paper is to systematically study the affect of transport of the diffusant on the deformation of the solid and vice versa, and their implication in modeling degradation/healing of materials. We show that the coupled response is both qualitatively and quantitatively different from the uncoupled response. Copyright © 2011 John Wiley & Sons, Ltd.
Robust imposition of Dirichlet boundary conditions on embedded surfaces
Authors: Hautefeuille Martin , Annavarapu Chandrasekhar , Dolbow John E.
Published: November 2011

We develop both stable and stabilized methods for imposing Dirichlet constraints on embedded, three‐dimensional surfaces in finite elements. The stable method makes use of the vital vertex algorithm to develop a stable space for the Lagrange multipliers together with a novel discontinuous set of basis functions for the multiplier field. The stabilized method, on the other hand, follows a Nitsche type variational approach for three‐dimensional surfaces. Algorithmic and implementational details of both methods are provided. Several three‐dimensional benchmark problems are studied to compare and contrast the accuracy of the two approaches. The results indicate that both methods yield optimal rates of convergence in various quantities of interest, with the primary differences being in the surface flux. The utility of the domain integral for extracting accurate surface fluxes is demonstrated for both techniques. Copyright © 2011 John Wiley & Sons, Ltd.
Psychological distress in cancer survivors: the further development of an item bank
Authors: Smith Adam B. , Armes Jo , Richardson Alison , Stark Dan P.
Published: November 2011

Objective

Assessment of psychological distress by patient report is necessary to meet patients' needs throughout the cancer journey. We have previously developed an item bank to assess psychological distress but not evaluated it for cancer survivors. Our first aim in this study was to test whether we could extend our item bank to include cancer survivors. The second aim was to examine whether the item bank could assess positive affect as a single construct alongside negative psychological symptoms.

Methods

Responses from 1315 cancer survivors to the Hospital Anxiety and Depression Scale (HADS) and the Positive and Negative Affect Scale (PANAS) were considered for inclusion in a pre‐existing item bank created from a heterogeneous sample of 4914 cancer patients. Differential item functioning (DIF) was used to assess whether HADS responses drawn from the two samples were equivalent. Common‐item equating was used to anchor the shared (HADS) items, whilst the PANAS items were added. Item fit was evaluated at each stage, and misfitting items were removed. Unidimensionality was assessed with a principal components factor analysis.

Results

The DIF analysis did not reveal any differences between the HADS item locations from the two samples. Three misfitting PANAS items were removed, resulting in a final unidimensional bank of 80 items with good internal reliability (α = 0.85).

Conclusion

The new item bank is valid for use across the cancer journey, including cancer survivors, and modestly improves the assessment of all levels of psychological distress and positive psychological function. Copyright © 2011 John Wiley & Sons, Ltd.
Suitability of Soxhlet Extraction to Quantify Microalgal Fatty Acids as Determined by Comparison with In Situ Transesterification
Authors: McNichol Jesse , MacDougall Karen M. , Melanson Jeremy E. , McGinn Patrick J.
Published: November 2011

To assess Soxhlet extraction as a method for quantifying fatty acids (FA) of microalgae, crude lipid, FA content from Soxhlet extracts and FA content from in situ transesterification (ISTE) were compared. In most cases, gravimetric lipid content was considerably greater (up to sevenfold) than the FA content of the crude lipid extract. FA content from Soxhlet lipid extraction and ISTE were similar in 12/18 samples, whereas in 6/18 samples, total FA content from Soxhlet extraction was less than the ISTE procedure. Re‐extraction of residual biomass from Soxhlet extraction with ISTE liberated a quantity of FA equivalent to this discrepancy. Employing acid hydrolysis before Soxhlet extraction yielded FA content roughly equivalent to ISTE, indicating that acidic conditions of ISTE are responsible for this observed greater recovery of FA. While crude lipid derived from Soxhlet extraction was not a useful proxy for FA content for the species tested, it is effective in most strains at extracting total saponifiable lipid. Lipid class analysis showed the source of FA was primarily polar lipids in most samples (12/18 lipid extracts contained <5% TAG), even in cases where total FA content was high (>15%). This investigation confirms the usefulness of ISTE, reveals limitations of gravimetric methods for projecting biodiesel potential of microalgae, and reinforces the need for intelligent screening using both FA and lipid class analysis.
Cognitive impairment in nondemented oldest‐old: Prevalence and relationship to cardiovascular risk factors
Authors: Peltz Carrie B. , Corrada María M. , Berlau Daniel J. , Kawas Claudia H.
Published: November 2011

Objective

To determine the prevalence and types of cognitive impairment in a sample of nondemented participants aged ≥90 (the oldest‐old) and to examine the relationships between cognitive impairment and cardiovascular risk factors.

Participants

The participants were 420 nondemented individuals from The 90+ Study, a study of aging and dementia in the oldest‐old. These participants were categorized into four nonoverlapping groups: normal cognition, amnestic mild cognitive impairment (aMCI), nonamnestic MCI (naMCI), and other cognitive impairment (OCI). History of cardiovascular risk factors was assessed through self‐report.

Results

The overall prevalence of cognitive impairment in nondemented participants was 34.0% (95% CI: 29.5–38.5). The prevalence of OCI was highest (17.4%; 95% CI: 13.9–21.4), followed by aMCI (8.3%; 95% CI: 5.9–11.4) and naMCI (8.3%; 95% CI: 5.9–11.4). Normal cognition was present in 66.0% (95% CI: 61.2–70.5) of participants. History of hypertension and stroke were the only risk factors that varied between the groups, occurring more frequently in participants with naMCI (χ2 = 3.82; P < .05) and OCI (χ2 = 5.51; P < .05).

Conclusions

This study found a high prevalence of cognitive impairment in a sample of nondemented oldest‐old. We did not find a strong relationship between cardiovascular risk factors and the cognitive impairment groups, other than between hypertension and naMCI and stroke and OCI. Future studies comparing the incidence of dementia in these groups will ultimately determine their predictive utility in the oldest‐old.
Do waterfalls have value in themselves? A metamorphosis in the values of the Gimel waterfall in France
Authors: Haghe Jean-Paul
Published: November 2011

This paper describes the change of value ascribed to a waterfall (the Gimel fall in France) from the early 20th to present. Two movements of valuation are studied. The first movement corresponds to the transformation of the waterfall into a touristic site. This was triggered by Gaston Vuillier, a painter who fell in love with the site and decided to protect it; in this case the value changed from non-anthropocentric instrumental value to anthropocentric instrumental and extrinsic value. The second movement, which began at the end of the 20th century, demonstrates new environmental perceptions which have changed the valuation of the site from a non-anthropocentric intrinsic value to an anthropocentric instrumental value.
The problems of reforming of the International Stratigraphic Chart in terms of evolution of ecosystems (by the example of the Lower Paleozoic)
Authors: Kanygin A.V.
Published: November 2011

The hierarchial structure and conceptual bases of the International Stratigraphic Chart (ISC) were created during the first eight sessions of the International Geological Congress (IGC) (1878–1900) by the systematization and unification of mainly the West European regional stratigraphic references, except the Permian and, partly, Carboniferous systems with stratotypes in the Russian territory. In the next stage, the structure was refined and supplemented by on the basis of the same principles. Since the middle 1980s, a radical ISC reforming has been performed in the framework of the International Commission on Stratigraphy (ICS), which revealed the contradictory tendencies in the development of modern stratigraphy. They are expressed first of all in the principal difference between the new methodology of the “rational” substantiation of global stratigraphic references adopted by the ICS and the real practice of the development of their regional equivalents based not on the choice of chronometric markers for global correlations but on the revealing of natural geohistorical stages in the evolution of ecosystems, using the total set of paleontological, sedimentological, and isotope-chronometric data. The new approach is based mainly on the concept of the self-sufficiency of limiting types, i.e., monotaxon markers for graduating the ISC, which replace the stratotypes of subunits, their integral complex characteristics, reflecting the trends and periodicity of the Earth’s evolution. The negative consequences of this “rational” substantiation and revision of the stratigraphic references of the ISC are particularly obvious by the example of innovations in the subdivision of the Cambrian and Ordovician systems on the comparison of the new series and stages adopted by the ICS with the global ecosystem rebuildings in the Early Paleozoic.
Problems of Paleogene stratigraphy and paleogeography in the middle latitudes of Eurasia
Authors: Akhmet’ev M.A.
Published: November 2011

The present-day notions of the Paleogene history, paleogeography, and paleobiogeography of Central Asia middle latitudes are based on studies carried by A.L. Yanshin in the second quarter of the 20th century. Here, main phases in the geologic history of the West Siberian and Turan Plates and Turgai depression are considered. In the Paleocene and Eocene, these regions were key links of a continuous meridional marine communication system connecting the Tethys and Arctic Oceans. Before the emergence of the latitudinal Alpine–Himalayan orogenic belt, the Tethys and its marginal seas formed a united shelf area. The closest linkage of the water bodies and biota exchange between them existed in the Thanetian and in the first half of the Ypresian. There was intense heat transfer from tropical to higher latitudes through the entire system of epeiric seas and straits. From the end of the Paleocene, this system was supplemented and complicated by latitudinal straits that ensured the connection of the seas of the Northern Peri-Tethys with the Northern Sea basin and the Atlantic. The combination of two sea systems determined the climatic history of this region from the Paleocene till the Late Eocene. The Arctic Basin influenced mainly the structure of cold-water benthos, and the Tethys, the composition of planktonic biota in the photic zone. During the Bartonian and Priabonian, in the last phase of marine sedimentation, the West Siberian epeiric sea was completely isolated from the Arctic Basin and connected only with the Turan sea through the Turgai strait. The Azolla beds accumulated during the low stand of the World Ocean in desalted surface waters and in disoxic bottom waters inhabited by depauperated benthos. At the Eocene/Oligocene boundary, the drainage of the Tavda–Chegan sea was followed by the formation of an N-S-directed river network in the vast areas of West Siberia, Turgai, and the northern cis-Aral region. The climate was unstable, moderately warm to subtropical, with variable humidity. The formation of the Turgai ecotype of mesophytic conifer-broadleaved flora was completed by the end of the Early Oligocene.
Seismostratigraphic analysis of Paleogene deposits in the northern Aral area and northeastern Ustyurt
Authors: Antipov M.P. , Bykadorov V.A. , Volozh Yu.A. , Shlezinger A.E.
Published: November 2011

Seismostratigraphic analysis of Paleogene deposits in northeastern Ustyurt was carried out. Four seismostratigraphic complexes have been recognized: Paleocene–Ypresian, Lutetian–Bartonian (Tasaran unit), Bartonian–Priabonian (Saksaul’skaya–Chegan), and Oligocene. We have established for the first time the clinoform structure of the Tasaran and Saksaul’skaya–Chegan complexes, which explains various concepts of their age. Seismostratigraphic analysis must be an integral part of stratigraphic research, which will significantly increase the reliability of correlation between geological sequences.
Arid sedimentation in the oceans and atmospheric particulate matter
Authors: Lisitzin A.P.
Published: November 2011

Recent studies on the continental sources of aerosol production, transport and deposition to the ocean (natural sink) allowed us to recognize the possibility of long-range high-altitude (transoceanic) transport of aerosol dust of specific composition and properties. The dust consists of fine (micro- and nanosized) particles (94%, less than 2 μm) originated in the arid (undrained) tropical and subtropical regions extending into the oceans and are similar in composition to deep-sea (pelagic) red clays. Satellite and aircraft observation data were used to track trajectories of long-range (and transoceanic) transport of dust clouds. These data were coupled with direct shipboard measurements on ice core records and data on nuclear explosions and volcanic eruptions.

Several zones of arid sedimentation were identified based on climatic conditions (shortage of water), conditions of dust production, wind-blown transport at different altitudes and deposition onto the ocean surface. The main transport occurs at two altitude scales (from land to the cloud top and above) (5–7 km) where wind speed of 300 km/h will be critical for a long-range transport.

Three types of transport are identified based on the particle dynamics, composition and properties: 1—local (0–10 km from the source); 2—regional (100–1000 km); 3—global (over 1000 km). The finer particles are a product of local-scale transport with a total flux of 1.6 billion t/yr, which is almost equal to the net influx of the riverine terrigenous material to the pelagic zones of the oceans (outside the marginal filters). There are four main sources of aerosol dust, which is transported and deposited over arid oceanic regions. The arid oceanic regions account for about 1/3 of the modern ocean surface. During glacial periods, the sea-level drop of 100–120 m caused a significant increase in the size of arid regions due to the exposure of the shelf areas, which is equal to the area of the African continent. This caused 3–5 times higher dust emission, a decrease in the heat flux and in the transparency of the atmosphere. Comparison of ice core records and deep drilling data provide basis for studies on the ancient arid sedimentation.
Carbonate sedimentation in the Meso-Neoproterozoic basins in southern East Siberia and some problems of evolution of reef formation in the Precambrian
Authors: Khabarov E.M.
Published: November 2011

Diverse stromatolitic structures are recognized in the Meso-Neoproterozoic basins in southern East Siberia: simple (bioherms and biostromes), individual, barrier, shore reefs and reef-like structures, and large reef-like banks. These data and results of macro- and microscopic studies of stromatolites point to the leading role of microbial communities in the production of primary carbonate material. Most of the carbonate mud was supplied to the deep-water shelf zones, slopes, and plains of the Meso-Neoproterozoic East Siberian basins from shallow-water shelves. Analysis of the materials from almost all Precambrian carbonate complexes shows that the microbial communities have played the leading role in the generation of carbonate material since the Late Mesoarchean. Both the shallow- and deep-water Precambrian carbonate sedimentary systems have much in common with the Phanerozoic ones. Their diversity and development are controlled by a number of factors, which exert different effects in geodynamically different basins, and the carbonate systems of different ranks are fine indicators of various events in the basin evolution, from the low-amplitude eustatic fluctuations of the sea level to the global epochs of flooding and highstand of supercontinents. The absence of lime-producing organisms in the Precambrian determined the similar composition of carbonate rocks and sometimes the indistinct structure-morphologic differentiation of the Precambrian organogenic structures. The evolution of reef systems in the Precambrian was determined first of all by the evolution of the lithosphere, which periodically led to the formation and cessation of development of basins favorable for the mass evolution of microbial communities, and by the structural complication of microbial communities producing stromatolites. The epochs of stromatolite formation reduction and destruction of sea basins correlate well with the global epochs of the formation and highstand of supercontinents.
The geochemical and isotope (Sr, C, O) characteristics of the Vendian–Cambrian carbonate deposits of the Azyr-Tal Ridge (Kuznetsk Alatau): chemostratigraphy and sedimentogenesis environments
Authors: Letnikova E.F. , Kuznetsov A.B. , Vishnevskaya I.A. , Terleev A.A. , Konstantinova G.V.
Published: November 2011

Results of isotope (Sr, C, and O) and geochemical studies of the carbonate deposits of the Yenisei Group of the Azyr-Tal Ridge (Kuznetsk Alatau) are presented. Using the Sr and C isotope chemostratigraphy, the age restrictions for these deposits have been made. It is shown that the sediments of the Charyshtag, Bidzha, and Martyukhina Formations and the lower part of the Sorna Formation accumulated in the Late Vendian and Early Cambrian, at 580–530 Ma, and those of the upper part of the Sorna Formation, at 525–517 Ma. Their successive accumulation in the same sedimentary basin is not confirmed by the performed geochemical studies. The deposits of the upper part (members 2 and 3) of the Sorna Formation accumulated in a sedimentary basin of other type as compared with the rest underlying deposits of the Yenisei Group. For example, at least two types of shallow-water sea basins are recognized within Kuznetsk Alatau in the Late Vendian: shelf, localized within a block with a passive tectonic regime (Charyshtag, Bidzha, and Martyukhina Formations and lower part of the Sorna Formation), and oceanic, where accumulation proceeded within oceanic islands with underwater hydrothermal activity (upper part of the Sorna Formation).
Changing ichnofossil composition in the Callovian–Oxfordian sediments of the West Siberian basin as a reflection of sedimentation cyclicity
Authors: Yan P.A. , Vakulenko L.G.
Published: November 2011

We summarize the results of the integrated lithologic and ichnofacies studies of the Callovian–Oxfordian sediments in the West Siberian sedimentary basin on the basis of core samples from more than 200 wells. In the sections of various structurefacies zones, ten ichnofossils of the ichnofacies Skolithos, Cruziana, and Zoophycos have been identified and spatial variations in the species composition of ichnofacies assemblages have been traced. It has been found that lateral and vertical variations in the ichnofossil distribution agree with the regional structural patterns of the Vasyugan Horizon and are related to the Callovian–Oxfordian cyclic turnovers of the basin depositional systems.
Structure and depositional environment of the Vasyugan Horizon (Upper Bathonian–Oxfordian) in the Aleksandrovskoe arch area (West Siberia)
Authors: Vakulenko L.G. , Dul’tseva O.V. , Burleva O.V.
Published: November 2011

An integrated sedimentological study of the Vasyugan Horizon in the Aleksandrovskoe arch area was performed, during which its depositional environments were reconstructed and a series of paleogeographic maps was plotted. It has been established that shallow-marine, marginal-marine, transitional, and continental depositional environments existed here at various stages. Most of the arch area is characterized by sections of the transitional Naunak–Vasyugan and Vasyugan–Naunak types; the westernmost part, by sections of the Vasyugan type, and the easternmost part, by sections of the Naunak type. The sand beds of the J1 horizon are low-quality reservoirs, whereas those on the western slope and the northern pericline of the Aleksandrovskoe arch are of better quality.
A tectonogeodynamic model for the junction zone between the Fennoscandian and Sarmatian segments of the East European Platform
Authors: Garetsky R.G. , Karatayev G.I.
Published: November 2011

Seismic gravity modeling along the Eurobridge-96–Eurobridge-97 DSS geotransects has shown that the Central Belarus suture zone formed in the Paleoproterozoic as a results of the subduction and collision processes at the convergent junction of the Fennoscandian and Sarmatian segments of the East European Platform. The influence of pre-Riphean processes on the subsequent tectonic events occurring on the territory of Belarus during the Phanerozoic has been established.
Collision-related metamorphic complexes of the Yenisei Ridge: their evolution, ages, and exhumation rate
Authors: Likhanov I.I. , Reverdatto V.V. , Kozlov P.S.
Published: November 2011

In the Transangarian part of the Yenisei Ridge, rocks near the thrusts in area of the Tatarka deep fault underwent the medium-pressure kyanite-sillimanite grade metamorphism, which resulted locally in the progressive replacement of andalusite by kyanite, the development of new mineral assemblages and deformation structures. A number of features special to kyanite-sillimanite grade metamorphism, such as a relatively small measured thickness of the medium-pressure zones (from 2.5 to 7 km) and a gradual increase in pressure towards the thrust faults from 4.5–5 kbar to 6.5–8 kbar with slightly increasing temperature, suggest a low metamorphic field gradient with dT/dH ranging from 7 to 12 °C/km. These specific features are typical of collisional metamorphism during overthrusting of continental blocks and suggest a near-isothermal loading in accordance with the transient emplacement of thrust sheets and subsequent rapid exhumation and erosion. Based on geothermobarometry and 40Ar-39Ar mica ages, the proposed model suggests that, given an estimated exhumation rate of 0.368 mm/yr for a number of areas, the peaks of collision-related metamorphism occurred at 849–862 and 798–802 Ma. The older metamorphic complexes (Angara, Mayakon, Teya, and Chapa areas) are interpreted to have formed by thrusting of Siberian cratonal blocks onto the Yenisei Ridge, as indicated by geophysical observations and regional provenance studies. A later phase of the repeated collisional metamorphism appears to have been associated with reverse motion of some smaller blocks along higher-order splay faults in the eastward direction (Garevka area). On a regional scale, this may result from collision and accretion of a microcontinent split off the craton at the Early–Middle Riphean boundary onto the Central Angara terrane.
Seismostratigraphic characteristics, tectonic evolution, and petroleum potential of the northwestern part of the Kaimysovy petroliferous region
Authors: Kontorovich D.V.
Published: November 2011

Structural and isopach maps of seismogeologic megacomplexes were constructed on the basis of an integrated interpretation of seismic prospecting, GIS, and deep drilling data. The tectonic evolution of the northwestern part of the Kaimysovy arch and adjacent areas of the Yugan megadepression in the Mesozoic–Cenozoic was analyzed, and the main stages of formation of structures of different orders were established. An analysis of geological and geophysical data shows that the Larlomkiny and Pervomaiskoe–Vesennii swells have radically different formation histories despite their similar modern tectonic structure.

The results of the investigations suggest that most of the local uplifts in the Bazhenovka Formation, in particular, the Larlomkiny structure bearing an Upper Jurassic oil pool, formed in the Neocomian due to the inherited growth of erosional-tectonic salients (ETS) of the pre-Jurassic basement, and then developed only slightly. The large tectonic structures of the first order—the Kaimysovy arch and the Yugan megadepression and the Pervomaiskoe–Vesennii swell—a big trap associated with one of the largest oil fields of southeastern West Siberia, completed their formation in the Cenozoic.
The phase composition of crystal-fluid nanoinclusions in alluvial diamonds in the northeastern Siberian Platform
Authors: Logvinova A.M. , Wirth R. , Tomilenko A.A. , Afanas’ev V.P. , Sobolev N.V.
Published: November 2011

The phase composition of crystal-fluid nanoinclusions in two types of placer diamonds of unknown genesis from the northeastern Siberian Platform (Ebelyakh diamondiferous region) has been first studied by transmission electron microscopy including electron diffraction, analytical electron microscopy (AEM), electron energy loss spectroscopy (EELS), and chromatography. The type I diamonds are transparent dodecahedroids, and the type II ones, widespread in this region, are dark rounded crystals assigned to variety V according to Orlov’s mineralogical classification. Isotopic and IR-Fourie spectroscopic studies showed that the type II diamonds have a strongly light carbon isotope composition (δ13Cav = –22.4‰) and high concentrations of nitrogen admixture (1100–1800 ppm). Nitrogen is present mainly as an aggregate. It is shown that all inclusions no larger than 400 nm are polyphase particles consisting of solid (silicate, oxide, carbonate, salt) and fluid phases. The type I diamonds bear high-Mg carbonatite inclusions (up to 100 nm) consisting of magnesite, dolomite, Fe-spinel, and clinohumite. The fluid phase has high concentrations of K, Cl, and O. The inclusions are similar in composition to the near-solidus melts of saturated carbonatized peridotites; thus, they might have resulted either from the crystallization of the parental melt or from the quenching and crystallization of deep-seated carbonate-silicate melt. The type II diamonds bear low-Mg carbonatite polyphase nanoinclusions consisting of Ba-, Sr-, and Ca,Fe-carbonatites, K,Ba-phosphates, Ti,Si- and Ti,Al-phases, and abundant fluid segregations filled mainly with CO2, N, and hydrocarbons. These melts/solutions might have been supplied from subducted rocks of the oceanic and, partly, continental Earth’s crust. The enrichment of these inclusions in incompatible elements might evidence the percolation of salt fluids enriched in Ba, Sr, P, Ti, K, and Cl through carbonatized eclogites.
Fibrous diamonds from the placers of the northeastern Siberian Platform: carbonate and silicate crystallization media
Authors: Zedgenizov D.A. , Ragozin A.L. , Shatsky V.S. , Araujo D. , Griffin W.L.
Published: November 2011

The first data are presented on the compositions of microinclusions in fibrous diamonds from the Ebelyakh placers, northeastern Siberian Platform. Their fluid/melt microinclusions are of silicate or carbonate compositions. In general, the trace element patterns for the microinclusions correspond to kimberlites and carbonatites. The major-element composition differs significantly; for example, the microinclusions are considerably enriched in K and Na. In two of the studied diamonds, the microinclusion compositions differ considerably in the cores and rims. In one of them, the composition of the medium changes from chloride–carbonate to predominantly carbonate (sample HI-90); in the other one, from carbonate to silicate (sample HI-98). Similar carbon isotope characteristics of diamonds with microinclusions of two contrasting media might suggest their crystallization from a mantle reservoir with the same carbon isotope characteristics. The geochemical features of the microinclusions in the placer diamonds revealed their relationship with protokimberlitic carbonate–silicate fluids. Such fluids might result from the metasomatic interaction of volatiles and/or the low-degree partial melting of peridotite and eclogite substrates.
Genesis of scapolite from granulites (lower-crustal xenoliths from the Pamir diatremes): results of study of melt inclusions
Authors: Madyukov I.A. , Chupin V.P. , Kuzmin D.V.
Published: November 2011

The results of mineralogical and thermobarogeochemical studies of lower-crustal xenolith of scapolite-bearing granulites from the fergusite-porphyry diatremes pipes in Southeastern Pamir (Tajikistan) are presented. All minerals (including garnet, clinopyroxene, and scapolite) of these granulites contain primary melt inclusions, which were studied using thermometric and microprobe methods (EPMA, SIMS, Raman spectroscopy). We have established that their compositions correspond to acid (from rhyodacites to rhyolites), essentially potassic melts of normal and high alkalinity with H2O ≤ 4 wt.%, Cl ≤ 0.8 wt.%, and CO2 ~ 1 wt.%. The melts are depleted in HREE and have high Th/U ratios (7.7–9.4). Study of melt inclusions using mineralogical thermobarometers showed that the scapolite-bearing granulite crystallized at ~1000 °C and ~15 kbar. This rock resulted, most likely, from the incongruent melting of carbonate-bearing biotite-quartz-plagioclase substrate in the lower crust, which was accompanied by the crystallization of garnet, clinopyroxene, sphene, plagioclase, and scapolite trapping microportions of acid melts as inclusions. The minerals crystallized not from melt but in its presence. High-Ca scapolite (Me67–69) crystallized instead of plagioclase when the melts reached high contents of CO2 (~1 wt.%) and Cl (≤ 0.8 wt.%) in the presence of CO2-rich fluid.
Rhönite in alkali basalts: silicate melt inclusions in olivine phenocrysts
Authors: Sharygin V.V. , Kóthay K. , Szabó Cs. , Timina T.Ju. , Török K. , Vapnik Ye. , Kuzmin D.V.
Published: November 2011

Silicate melt inclusions containing rhönite Ca2(Mg,Fe2+)4Fe3+Ti[Al3Si3O20] were studied in olivine phenocrysts from alkali basalts of six different volcanic regions: Udokan Plateau, North Minusa Depression, Tsagan-Khurtei Ridge (Russia), Bakony-Balaton Highland, Nógrád-Gömör Region (Hungary) and Makhtesh Ramon (Israel). Rhönite-bearing silicate melt inclusions are relatively common phenomena in alkali basalts and usually coexist with inclusions containing no rhönite. Inclusions with rhönite generally occur in the core of the olivine phenocrysts. According to heating experiments and CO2 microthermometry, all the rhönite-bearing inclusions in core of the olivine phenocrysts were trapped as silicate melt at T > 1300 °C and P > 3–5 kbar. Rhönite crystallized in a narrow temperature range (1180–1260 °C) and P < 0.5 kbar. The petrography and thermometry of rhönite-bearing silicate melt inclusions show a general crystallization sequence: Al-spinel → rhönite → clinopyroxene → apatite → ± amphibole, Fe-Ti oxide (ilmenite or Ti-magnetite) → glass.

Majority of rhönites from melt inclusions have Mg/(Mg + Fe2+) > 0.5 and belong to Mg-rich species Ca2Mg4Fe3+Ti[Al3Si3O20]. There are no essential differences in chemistry among rhönites from olivine-hosted silicate melt inclusions from phenocryst, from groundmass of alkali basalts, from alteration products of kaersutitic amphibole mega/xenocrysts and of kaersutite in deep-seated xenoliths in alkali basalts. The rare occurrence of rhönite as essential constituent in rocks may be explained from its microstructural peculiarities. This mineral is an intermediate member of the polysomatic spinel-pyroxene series. Possibly, the structural feature of rhönite does explain why it is an unstable mineral in under changing crystallization conditions. In general, the presence and chemistry of rhönite may be used for rough estimation of temperature, pressure and oxygen fugacity during crystallization of alkali basalts.
Rhyolitic melts in eastern Transbaikalia and the North Caucasus: chemical composition, volatiles, and admixture elements (from data of study of melt inclusions in minerals)
Authors: Naumov V.B.
Published: November 2011

We studied melt inclusions in quartz phenocrysts from Late Jurassic rhyolites in eastern Transbaikalia (Strel’tsovka caldera) and in quartz, apatite, and plagioclase phenocrysts from rhyolites in the North Caucasus (North Ossetia and Tyrnyauz region). More than 15 uranium deposits and ore occurrences are known in the Strel’tsovka caldera, as well as Pb-Zn deposits in North Ossetia and the largest Mo-W deposit in the Tyrnyauz region. For the studies we used the inclusion homogenization methods and performed electron and ion microprobe analyses of glasses from more than 30 inclusions. The temperatures of the total homogenization of melt inclusions are shown to depend directly on the initial melting points of their glasses, which might be due to the different contents of volatiles (first of all, water). The experiments on determining the time required for the homogenization and heterogenization of melt inclusions showed that the melts in the inclusions are of different viscosity and homogenize at different temperatures. The rhyolitic melts from eastern Transbaikalia and the North Caucasus have similar contents of rock-forming elements (average, wt.%): 75.0 and 74.6 SiO2, 0.08 and 0.05 TiO2, 11.0 and 12.3 Al2O3, 0.74 and 0.40 FeO, 0.04 and 0.05 MgO, 0.29 and 0.64 CaO, 4.09 and 3.79 Na2O, and 4.30 and 4.24 K2O, respectively. But these melts differ significantly in the contents of Cl (on average, 0.20 and 0.08 wt.%, respectively), F (1.07 and 0.09 wt.%), and some admixture elements. The melts from the first region are much richer in Zr, Nb, La, Ce, Th, and U but poorer in Sr, Ba, and Eu than the melts from the second region, which evidences their deeper differentiation. The revealed high contents of Th and U in the melts from the Strel’tsovka caldera agree with the literature data of the French geologists on the same caldera.
Heterogeneity in fluid characteristics in the Ramagiri–Penakacherla sector of the Eastern Dharwar Craton: implications to gold metallogeny
Authors: Bhattacharya S. , Panigrahi M.K.
Published: November 2011

The auriferous Penakacherla–Ramagiri schist belt is a part of the granite-greenstone terrain of the Eastern Dharwar Craton. It is surrounded by gneissose basement and has a close spatial association with the younger granitoid units. Fluid inclusion assemblages studied from quartz veins in schists, quartz veins in granites and matrix quartz in granite indicate heterogeneity in fluid characteristics with methane-poor aqueous-carbonic, methane-rich carbonic, low salinity aqueous and high salinity aqueous fluids. Coexisting aqueous and carbonic inclusions do not seem to be the product of phase separation of a parent aqueous-carbonic fluid on all instances. This is corroborated by the fact that the pure carbonic fluid is richer in methane than the carbonic component of the aqueous-carbonic inclusions. This warrants a separate source of carbonic fluid during deposition of the gold-quartz ± sulfide veins. A high salinity component in the fluid in the schist belt is unlikely to be contributed by metamorphism of the host volcanic units rather it is comparable to the high salinity fluid present in the closely associated granites. Thus it may be surmised that the heterogeneous fluid characteristics in the auriferous Penakacherla–Ramagiri schist belt raises the possibility of fluid derivation from diverse sources, including the granitoids, rather than from a single metamorphogenic source.
Formation conditions and composition of ore-forming fluids in the Promezhutochnoe gold and silver deposit (Central Chukchi Peninsula, Russia)
Authors: Volkov A.V. , Prokof’ev V.Yu.
Published: November 2011

The Promezhutochnoe and Sil’noe epithermal gold and silver deposits and ore bodies of eastern areas of the Sopka Rudnaya deposit have been discovered in the Maiskoe ore cluster, central Chukchi Peninsula, in terrigenous flysch strata of the basements of the Okhotsk–Chukchi volcanic belt. Fluid inclusions in quartz from gold ore veins of Promezhutochnoe have been studied. Similar deposits and occurrences have been found in the terrigenous-sedimentary framing of some intrusion domes in tectonomagmatic zones in the Upper Yana–Kolyma fold belt. Terrigenous strata of similar compositions host the Vysokovol’tnoe and Kosmanychi gold and silver deposits in central Kyzyl Kum and the Balei and Taseevka deposits in Transbaikalia. The richest Hishikari deposit (250 tons of gold, the mean content 60 g/t) in Japan also occurs in terrigenous strata of the basement beneath a volcanic rock cover. However, deposits other than Hishikari, Balei, or Taseevka are small. The causes of this fact are discussed in the context of the geologic structure, chemical composition, and ore formation conditions in the Promezhutochnoe deposit. The main physicochemical parameters of the formation of the ores in this deposit are: temperature 247–194 °C, pressure 270–30 bar, salt concentration 4.3–2.9 wt.% NaCl equiv. The composition of the ore-forming fluids has been studied by gas chromatography, ion exchange chromatography, and inductively coupled plasma mass spectrometry.
The Gerfed gold deposit: fluids and PT-conditions for quartz vein formation (Yenisei Ridge, Russia)
Authors: Gibsher N.A. , Tomilenko A.A. , Sazonov A.M. , Ryabukha M.A. , Timkina A.L.
Published: November 2011

At the Gerfed gold deposit, fluid inclusions were studied by thermobarometry, gas chromatography, Raman spectroscopy, and ICP MS in quartz samples of three types: quartzites, Au-poor (<1–2 ppm) feathering veins, and Au-rich (>2.8–10 ppm) feathering veins. It has been found that these three types were produced from fluids differing in composition and thermobarogeochemical parameters. The quartzites formed from low-salinity (<7.0 wt.% NaCl equiv) homogeneous fluids of essentially aqueous–chloride composition at 120–230 °C and 0.1–0.5 kbar. The gas phase in these fluids comprises H2O, CO2, CH4, and N2, with CO2/(CO2 + H2O) = 0.04–0.15 and CO2/CH4 = 2.2–3.8. The Au-poor feathering veins formed from homogeneous and heterogeneous fluids at 150–300 °C and 0.5–2.0 kbar. The salinity of the fluids increased to 10 wt.% NaCl equiv. The gas phase in them comprises H2O, CO2, N2, and CH4. Here, CO2/(CO2 + H2O) = 0.09–0.17 and CO2/CH4 = 2.2–2.3. The Au-rich feathering veins formed from heterogeneous and more saline (6.0–23.3 wt.% NaCl equiv) CO2–H2O fluids at higher temperatures (150–400 °C) and pressures (1.1–2.5 kbar). In this fluid CO2/(CO2 + H2O) = 0.18–0.27 and CO2/CH4 = 4.1–20.8. All three quartz types show negative Eu anomalies and a distinct predominance of LREE over HREE. Differently directed trends of REE and Eu/Sm in the quartzites and feathering veins suggest that the fluids were produced from different sources. The fluids of the gold-bearing quartz veins are enriched in K, Li, and Rb, and those of the Au-poor feathering veins, in Sr and Na. The quartzites have low Rb and Sr and similar Na and K contents. Areas with a high and bonanza gold content in feathering-vein stockworks formed when high-temperature saline H2O–CO2 fluids were superposed on the Au-poor quartzites and feathering veins.
Ongonite–elvan magmas of the Kalguty ore-magmatic system (Gorny Altai): composition, fluid regime, and genesis
Authors: Sokolova E.N. , Smirnov S.Z. , Astrelina E.I. , Annikova I.Yu. , Vladimirov A.G. , Kotler P.D.
Published: November 2011

The Kalguty ore-magmatic system (OMS) is a complex combination of a granite pluton, a hydrothermal Mo–W deposit, pegmatites, greisens, and a belt of rare-metal (RM) and ultra-rare-metal (URM) elvan and ongonite dikes.

Studies of melt inclusions (MI) in quartz phenocrysts in the dike rocks have demonstrated that quenched glass has major element contents close to those of the dike rocks but rare elements (Li, Rb, Be, Cs) and P contents. This suggests that the MI represent magma at the stage preceding the dike emplacement. The MI in quartz from the URM rocks are poorer in Si, Fe, Mg, and REE than those in quartz from the RM rocks but richer in Cs, Rb, Nb, and Ta, like the URM rocks themselves. This indicates that the melts had segregated into RM and URM ones before the studied quartz phenocrysts began to crystallize. The composition of MI glass corresponds to “the albite trend” of differentiation, suggesting that the initial melt compositions were ongonitic, while their K enrichment and formation of elvan magma followed the crystallization of the quartz phenocrysts.

According to our estimates, the melt contained 6–7 wt.% H2O. The quartz phenocrysts crystallized in a heterogeneous medium consisting of a silicate melt and an aqueous fluid. The latter was a high-density supercritical fluid with 3–12 wt.% NaCl equiv. Variations in the gas and salt compositions of the fluid inclusions (FI) are attributed to the interaction between fluids of magmatic and hydrothermal systems. This possibility is confirmed by ample evidence of their coeval formation.

Quartz crystallization from the RM melts took place at 630–650 °C, whereas quartz from the URM melts formed at 20–30 °C lower temperatures. Quartz phenocrysts crystallized at 4.5–5.5 kbar. Additional estimates with regard to the mineral composition and quartz compressibility yielded values of 3–6.5 kbar.

A petrogenetic model of some crystallization stages of the dike rocks within the Kalguty OMS was constructed on the basis of the results obtained in this study. The melts which formed the dikes of the East Kalguty belt are derivatives of the same magma which formed the major-stage granite pluton. Quartz is present as intratelluric phenocrysts, which crystallized at considerably greater depths than those of the dike emplacement. Differentiation of the parental magma was accompanied by rare element and P accumulation. The compositions of the FI and MI confirm that the magma and hydrothermal system of the Kalguty OMS exchanged their substances. It is associated with the increasing K content of the melts and the subsequent elvan crystallization as well as considerable variations in the salt and gas compositions of the magmatic fluid inclusions.
Further Evidence That Facial Cues of Dominance Modulate Gaze Cuing in Human Observers
Authors: Jones Benedict C. , Main Julie C. , Little Anthony C. , DeBruine Lisa M.
Published: November 2011

Many studies have demonstrated a gaze-cuing effect in humans, whereby observers are quicker to respond to targets in locations cued by others’ gaze direction than they are to respond to uncued targets. Although researchers have generally suggested that this gaze-cuing effect is unaffected by facial cues other than gaze direction, recent work has challenged this view: Both human and macaque observers demonstrate greater gaze cuing when viewing conspecifics’ faces that possess physical cues associated with high dominance than when viewing those that possess physical cues associated with low dominance. In the current study, we tested for further evidence of dominance-contingent gaze cuing in women. We conducted a gaze-cuing experiment in which different individual female faces were used as cues and calculated the strength of the gaze-cuing effect for each face. Composite (i.e., average) faces manufactured from images of women who elicited particularly large gaze-cuing effects were perceived as more dominant than composites manufactured from images of women who elicited particularly small gaze-cuing effects. This result supports (1) the existence of dominance-contingent gaze-cuing in human observers and (2) the proposal that the gaze-cuing system is sensitive to facial cues other than gaze direction.
Does a Woman’s Skin Color Indicate Her Fertility Level?
Authors: Samson Nadine , Fink Bernhard , Matts Paul
Published: November 2011

Roberts et al. (2004 ) showed that perceived facial attractiveness of women is higher in the fertile phase of the menstrual cycle than in the luteal phase, suggesting the existence of visible cues of ovulation. However, the nature of such cues remains speculative. Here, in an initial pilot study, we test the hypothesis that changes in female facial skin coloration across the menstrual cycle could be one of the signals that men have adapted to in order to assess female fertility. Spectrophotometric measurements of the facial skin color of normally ovulating Caucasian women (aged 24–29 years) were collected in the late follicular and midluteal phase of their menstrual cycle. Facial images were also taken in both sessions and judged for attractiveness and health by a panel of German men (aged 16–37 years). In line with Roberts et al. (2004 ), our results show that men perceive women in the late follicular phase to be significantly more attractive and healthier than those in the midluteal phase. However, we did not detect any significant differences in objective measurements of skin color between the two phases. We conclude that the increase in male perception of female facial attractiveness and health in the fertile phase of the menstrual cycle is not caused by a change in overall skin color and/or lightness.