Kobyashevite, Cu5(SO4)2(OH)6·4H2O, a new devilline-group mineral from the Vishnevye Mountains, South Urals, Russia     

Igor V. Pekov  Natalia V. Zubkova  Vasiliy O. Yapaskurt  Dmitriy I. Belakovskiy  Nikita V. Chukanov  Anatoly V. Kasatkin  Aleksey M. Kuznetsov  Dmitry Y. Pushcharovsky 《Mineralogy and Petrology》2013,107(2):201-210

A new mineral kobyashevite, Cu₅(SO₄)₂(OH)₆·4H₂O (IMA 2011–066), was found at the Kapital’naya mine, Vishnevye Mountains, South Urals, Russia. It is a supergene mineral that occurs in cavities of a calcite-quartz vein with pyrite and chalcopyrite. Kobyashevite forms elongated crystals up to 0.2 mm typically curved or split and combined into thin crusts up to 1?×?2 mm. Kobyashevite is bluish-green to turquoise-coloured. Lustre is vitreous. Mohs hardness is 2½. Cleavage is {010} distinct. D(calc.) is 3.16 g/cm³. Kobyashevite is optically biaxial (?), α 1.602(4), β 1.666(5), γ 1.679(5), 2 V(meas.) 50(10)°. The chemical composition (wt%, electron-microprobe data) is: CuO 57.72, ZnO 0.09, FeO 0.28, SO₃ 23.52, H₂O(calc.) 18.39, total 100.00. The empirical formula, calculated based on 18 O, is: Cu_4.96Fe_0.03Zn_0.01S_2.01O_8.04(OH)_5.96·4H₂O. Kobyashevite is triclinic, $ P\overline{\,1 } $ , a 6.0731(6), b 11.0597(13), c 5.5094(6)?Å, α 102.883(9)°, β 92.348(8)°, γ 92.597(9)°, V 359.87(7)?ų, Z?=?1. Strong reflections of the X-ray powder pattern [d,Å-I(hkl)] are: 10.84–100(010); 5.399–40(020); 5.178–12(110); 3.590–16(030); 2.691–16(20–1, 040, 002), 2.653–12(04–1, 02–2), 2.583–12(2–11, 201, 2–1–1), 2.425–12(03–2, 211, 131). The crystal structure (single-crystal X-ray data, R?=?0.0399) сontains [Cu₄(SO₄)₂(OH)₆] corrugated layers linked via isolated [CuO₂(H₂O)₄] octahedra; the structural formula is CuCu₄(SO₄)₂(OH)₆·4H₂O. Kobyashevite is a devilline-group member. It is named in memory of the Russian mineralogist Yuriy Stepanovich Kobyashev (1935–2009), a specialist on mineralogy of the Urals.  相似文献   

Record-breaking warming in the Kamchatka Current halocline     

Rogachev  Konstantin  Shlyk  Natalia 《Ocean Dynamics》2021,71(5):545-557

Ocean Dynamics - We used historical CTD observations and Argo data to obtain the characteristics of the Kamchatka Current halocline and its eddies. Kamchatka Current eddies have a cold low salinity...  相似文献   

Seasonal and inter-annual variability of water quality in the Uruguay River,Argentina     

Juan C. Colombo  Carlos N. Skorupka  Claudio Bilos  Leandro Tatone  Natalia Cappelletti  M. Carolina Migoya 《水文科学杂志》2013,58(6):1155-1163

Abstract

Water quality of the Uruguay River was evaluated with multi-parametric (temperature, turbidity, conductivity, pH, dissolved oxygen) and sediment trap data (particle flux, total organic carbon and nitrogen contents) and correlated to precipitation, river discharge and El Niño Southern Oscillation (ENSO) indices for the period 2006–2011. Hydro-meteorological parameters averaged 24–85% variability with coincident precipitation (200–400 mm month^-1), discharge (7000–28 000 m³ s^-1) and turbidity peaks (50–80 NTU) in the austral spring, and absolute maxima during the El Niño 2009 episode. Spectral analysis of discharge and sea-surface temperature anomaly (SSTA) showed consistent variance maxima at approx. 3 and 1.5 years. Deseasonalized discharge was significantly correlated to SSTA. During river floods, pH decreased (from 7.5 to 6.6) and particle dynamics peaked (turbidity: 15–80 NTU; vertical fluxes: 20–200 g m^-2 d^-1; total solid load: <1000 to 100 000 t d^-1),whereas TOC remained stable (3.2 ± 0.8%) and C/N ratios increased (10–12) due to the higher contribution of terrestrial detritus.  相似文献   

An event-based conceptual model for context-aware movement analysis     

Gennady Andrienko  Natalia Andrienko  Marco Heurich 《International journal of geographical information science》2013,27(9):1347-1370

Current tracking technologies enable collection of data, describing movements of various kinds of objects, including people, animals, icebergs, vehicles, containers with goods and so on. Analysis of movement data is now a hot research topic. However, most of the suggested analysis methods deal with movement data alone. Little has been done to support the analysis of movement in its spatio-temporal context, which includes various spatial and temporal objects as well as diverse properties associated with spatial locations and time moments. Comprehensive analysis of movement requires detection and analysis of relations that occur between moving objects and elements of the context in the process of the movement. We suggest a conceptual model in which movement is considered as a combination of spatial events of diverse types and extents in space and time. Spatial and temporal relations occur between movement events and elements of the spatial and temporal contexts. The model gives a ground to a generic approach based on extraction of interesting events from trajectories and treating the events as independent objects. By means of a prototype implementation, we tested the approach on complex real data about movement of wild animals. The testing showed the validity of the approach.  相似文献   

Experimental shock metamorphism of the L4 ordinary chondrite Saratov induced by spherical shock waves up to 400 GPa     

Natalia S. BEZAEVA  Dmitri D. BADJUKOV  Pierre ROCHETTE  Jérôme GATTACCECA  Vladimir I. TRUKHIN  Evgeny A. KOZLOV  Minoru UEHARA 《Meteoritics & planetary science》2010,45(6):1007-1020

Abstract– We carried out shock experiments on macroscopic spherical samples of the L4 ordinary chondrite Saratov (natural shock stages S2–S3), using explosively generated spherical shock waves with maximum peak pressures of 400 GPa and shock‐induced temperatures >800 °C (up to several thousands °C). The evolution of shock metamorphism within a radius of the spherical samples was investigated using optical and scanning electron microscopy, microprobe and magnetic analyses as well as Mössbauer spectroscopy and X‐ray diffraction techniques. Petrographic analyses revealed a shock‐induced formation of three different concentric petrographic zones within the shocked samples: zone of total melting (I), zone of partial melting (II), and zone of solid‐state shock features (III). We found a progressive pressure‐induced oxidation of Fe‐Ni metal, whose degree increased with increasing shock peak pressure. The amount of FeO within zone I increased the factor of 1.4 with respect to its amount in the unshocked Saratov sample. This suggests that within zone I about 70 wt% of the initial metallic iron was oxidized, whereas magnetic analyses showed that about 10 wt% of it remained intact. This strongly supports the hypothesis that, in addition to oxidation, a migration of metallic iron from the central heavily shocked zone I toward less shocked peripheral zone took place as well (likely through shock veins where metallic droplets were observed). Magnetic analyses also showed a shock‐induced transformation of tetrataenite to taenite within all shocked subsamples, resulting in magnetic softening of these subsamples (decrease in remanent coercivity). These results have important implications for extraterrestrial paleomagnetism suggesting that due to natural impact processes, the buried crustal rocks of heavily cratered solid solar system bodies can have stronger remanent magnetism than the corresponding surface rocks.  相似文献   

Acoustic backscatter by schools of adult Atlantic mackerel     

Gorska  Natalia; Korneliussen  Rolf J.; Ona  Egil 《ICES Journal of Marine Science》2007,64(6):1145-1151

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Comment on “Geophysical evidence for a large impact structure on the Falkland (Malvinas) Plateau”          下载免费PDF全文

Wolf Uwe Reimold  Alvaro P. Crósta  Christian Koeberl  Natalia Hauser 《地学学报》2017,29(6):409-410

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Environmental change in the Ría de Vigo,NW Iberia,since the mid‐Holocene: new palaeoecological and seismic evidence     

Castor Muñoz Sobrino  Soledad García‐Gil  Jorge Iglesias  Natalia Martínez Carreño  Javier Ferreiro Da Costa  Ramón Alberto Díaz Varela  Alan Judd 《Boreas: An International Journal of Quaternary Research》2012,41(4):578-601

Pollen analyses (pollen, dinocysts and others) were combined with high‐resolution seismic‐stratigraphy sequences to reconstruct environmental dynamics and regional sea‐level (RSL) changes in a ria in NW Iberia. The chronological framework was established using radiocarbon dating and pollen markers that are related to a number of historical events. Major intensifications of the regional upwelling regime occurred during predominant NAO positive stages, dated to c. 4600–4300, 3800–3600, 3200–2700 and 2600–2400 cal. a BP. The regional Early Highstand System Tract spans from before 4500 to c. 3200 cal. a BP. During this period RSL was still rising, but several short episodes of higher terrestrial influence were detected between c. 4300–3800 and 3600–3200 cal. a BP. A readjustment occurred between 3200 and 2300 cal. a BP, including the first stage of relative sea‐level drop (2.8 ka event) dated to 3200–2800 cal. a BP, with the RSL recovering between 2800 and 2300 cal. a BP. The subsequent Later Highstand System Tract, after 2300 cal. a BP, corresponds to a final period of rising sea level that caused the final inundation of San Simón Bay. Since then, only minor changes in relative sea level can be postulated (e.g. towards the end of the Roman Period, in the Middle Ages and during the Little Ice Age). This new evidence is consistent with most of the available palaeoecological and historical information, but it provides a more detailed, near‐complete succession of simultaneous changes occurring in both the terrestrial and the marine ecosystems.  相似文献   

A reassessment of late glacial – Holocene diatom oxygen isotope record from Lake Baikal using a geochemical mass‐balance approach     

Anson W. Mackay  George E. A. Swann  Melanie J. Leng  David W. Morley  Natalia Piotrowska  Patrick Rioual  Dustin White 《第四纪科学杂志》2011,26(6):627-634

We present a new palaeoenvironmental record of hydrological variability in Lake Baikal, based on re‐modelled δ¹⁸O_diatom values of diatom silica (δ¹⁸O_modelled), where the residual contaminants are identified and compensated for using electron optical imaging and whole‐sample geochemistry. δ¹⁸O_modelled interpretations are based on the balance between rivers with high δ¹⁸O values and rivers with low δ¹⁸O values. Isotopic variability is related to latitudinal differences in precipitation which feed these rivers. The δ¹⁸O_modelled record suggests that rather moist conditions prevailed in the Lake Baikal region during the latter stages of the Younger Dryas. Throughout the Holocene, episodes of low δ¹⁸O_modelled values are, in general, in good agreement with increases in percentage haematite‐stained grains in North Atlantic sediments (indicative of ice‐rafted debris events). Rivers with southerly catchments dominate fluvial input especially between c. 3.3 and 2 cal ka BP, concurrent with high precipitation in the Lake Baikal region. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

Oil pipeline construction in Eastern Siberia: Implications for indigenous people     

Natalia Yakovleva 《Geoforum》2011,42(6):708-719

Traditional economic activities, lifestyles and customs of many indigenous peoples in the Russian North, such as reindeer herding, hunting and fishing, are closely linked to quality of the natural environment. These traditional activities that constitute the core of indigenous cultures are impacted by extractive sector activities conducted in and around traditional territories of indigenous peoples. This paper examines implications of an oil pipeline development in Eastern Siberia on the Evenki community in the Aldan district of the Republic of Sakha (Yakutia). It examines community concerns about potential environmental damage and impacts on traditional livelihood. The paper analyses the interaction of indigenous communities with the pipeline project through interrogation of elements such as impact assessment, consultation, compensation, benefits, communication and public activism. The paper discusses how state policy and industry’s approach towards land rights and public participation affects the position of indigenous peoples and discusses barriers for their effective engagement. The analysis shows a number of policy failures in the protection of traditional natural resource use of indigenous peoples and provision of benefits with regards to the extractive sector that leave indigenous peoples marginalised in the process of development. There is a need to involve indigenous peoples on the basis of dialogue and partnership, improve regulation and shift industry’s approach towards consideration and engagement.  相似文献