Atmospheric observations of liquid water in cloud and of chemical species in aerosols and gases near the ground and in fallen snow at Svalbard, Arctic

Columnar observations of liquid water and of radar echo intensity in cloud were carried out, using a microwave radiometer and a vertically pointing radar respectively, in Ny-Ålesund, Svalbard. Chemical concentrations were also measured in aerosols, gases and snowfalls. Clouds with a large proportion of liquid water moved over the site after snow clouds, with a much lower liquid water content, had been present for about 16 h. The mass concentrations of most chemical species in snowfalls were lower from the first set of clouds than the second. The NO₃⁻ and SO₄²⁻ concentrations in gases and aerosols associated with the first set of clouds were higher than in the second set, but Cl⁻ concentration was less for the first set than the second.     

Clay Minerals and Geotechnical Index Properties of Marine Clays in East Asia

Clay mineral composition and geotechnical index properties of marine clays collected from Singapore, Korea, and Japan were investigated, and the correlation of clay mineral composition with the consistency limits and activity of the clays was examined. Predominant clay minerals were kaolinite for Singapore clay, kaolinite, vermiculite, and illite for Pusan clay, and smectite for Hachirogata and Ariake clay from Japan. The activity of clay indicates that Singapore clay is classified as normal or inactive, Pusan clay as normal, and Hachirogata and Ariake clays mostly as active. Significant positive correlations were found between smectite percentage in bulk soil and the liquid and plastic limits of the clays.     

Thermochemistry of sulfide liquids IV: density measurements and the thermodynamics of O–S–Fe–Ni–Cu liquids at low to moderate pressures

We present the results of a series of density experiments in the system O–S–Fe–Ni–Cu. These experiments were designed to extend our understanding of the physical properties of sulfide liquids, and to extend one-bar thermochemical models for sulfide liquids to apply to low to moderate pressures. Density measurements indicate both positive and negative deviations from linear mixing of partial molar volumes across this five-dimensional composition space. In terms of the homogeneous speciation model of Kress (in Contrib Mineral Petrol 154:191–204, 2007), the best fit to experimental data can be achieved by starting with a model where the volume of formation reaction for associated species initially is set to zero. Further refinement of this first-order fit yields a volume mixing model which reproduces experimental data to within nearly the estimated experimental uncertainty. Experimental ultrasonic and X-ray absorption data from the literature, along with the bulk modulus–volume relation of Anderson and Nafe (J Geophys Res 16:3951–3963, 1965), allow the estimation of the pressure dependence of partial molar volumes for sulfide liquid species. The resulting combined thermochemical model should be valid to about 2,000 K and 3 GPa. Application of this thermochemical model in a simple adiabatic magma ascent scenario confirms earlier work suggesting that the pressure dependence of sulfur solubility in sulfide-saturated magma will decrease with increasing pressure along geologically reasonable paths in P–T–– space.     

Comparison of laminar model,RANS, LES and VLES for simulation of liquid sloshing

Liquid sloshing in storage tank is a fundamental problem of great engineering importance. Sloshing motion can be laminar or turbulent. However, the necessity for inclusion of turbulence in CFD simulation of sloshing flows has not yet been established. In this paper, three roll–induced sloshing cases are studied to assess the merits and shortcomings of the laminar model and three most–commonly used turbulence models (RANS k–ε, LES and Very LES). To overcome the deficiencies in the RANS and LES, the new Very LES (VLES) model, which combines the RANS k–ε and LES, is developed in this paper. The free surface profiles are reconstructed by a coupled Level–Set and Volume–of–Fluid (CLSVOF) method. To the authors’ knowledge, the comprehensive and systematical assessment of the effect of turbulence on sloshing simulation has not been reported in the literature. The numerical results are evaluated using experimental measurements from Delorme and Souto−Iglesias. The present study indicates that the inclusion of an appropriate turbulence model has a profound influence on the simulations of violent and non–violent sloshing flows. The VLES and LES models can provide accurate predictions of free surface profiles and impact pressures, whereas the laminar flow assumption and the RANS model cannot adequately capture the energy dissipation in the sloshing simulation and lead to the inaccurate flow predictions.     

硅酸盐-盐（硫酸盐）流体不混溶：蒙古南部Mushugai-Khuduk含火成碳酸岩杂岩体矿物中的熔体包裹体研究

Crystalline and melt inclusions were studied in garnet,diopside,potassium feldspar,and sphene from the garnet syenite porphyry of the carbonatite-bearing complex Mushugai-Khuduk,southern Mongolia.Phlogopite,clinopyroxene,albite,potassium feldspar,spheric,wollastonite,magnetite,Ca and Sr sulfates,fluorite,and apatite were identified among the crystalline inclusions. The melt inclusions were homogenized at 1010～1080℃and analyzed on an electron microprobe.Silicate,salt,and combined silicate- salt melt inclusions were found.Silicate melts show considerable variations in SiO_2 concentration(56 to 66wt% ),high Na_2O K_2O (up to 17wt% ),and elevated Zr,F,and C1 contents.In terms of bulk rock chemistry,the silicate melts are alkali syenites.During thermometric experiments,salt melt inclusions quenched into homogeneous glasses of predominantly sulfate compositions containing no more than 1.3wt% SiO_2.These melts are enriched in alkalis,Ba,Sr,P,F,and C1.The investigation of the silicate and salt melt inclusions in minerals of the garnet syenite porphyries indicate that these rocks were formed under influence of the processes of crystallization differentiation and magma separation into immiscible silicate and salt(sulfate)liquids.     

Immiscible two-liquid regions in the Fe-O-S system at high pressure: Implications for planetary cores

We have determined phase relations in the Fe-O and Fe-O-S systems in the range of 15-21 GPa and 1825-2300 °C. Below the liquidus temperatures, solid FeO and metallic liquids are observed in both the Fe-O and the Fe-O-S systems. An immiscible two-liquid region exists in the Fe-O binary system in the pressure range investigated, and the immiscibility gap between Fe-rich metallic liquid and FeO-rich ionic liquid does not greatly change with either pressure or temperature. On the other hand, an immiscible two-liquid region in the Fe-O-S ternary system narrows significantly with increasing pressure at constant temperature and vice versa, and it almost disappears at 21 GPa, and 2300 °C. Immiscible two-liquid regions are thus not expected to exist in the Fe-O-S system in the Earth's core, suggesting that both oxygen and sulfur can be incorporated into the core. Our results are consistent with a geochemical model for the core containing 5.8 wt.% oxygen and 1.9 wt.% sulfur as proposed by McDonough and Sun [McDonough, W.F., Sun, S.-S., 1995. The composition of the Earth. Chem. Geol. 120, 223-253].     

The liquid limit of peat and its application to the understanding of Irish blanket bog failures

Catastrophic failures of blanket bogs, involving the escape and outflow of large volumes of semi-liquid basal peat, are well-known phenomena in Ireland but have only very rarely been reported from elsewhere in the world. Their precise causes and mechanisms are as yet unclear. The liquid limit (w _L) was identified as a potentially useful indicator of the susceptibility of peat to such failure because peat has extremely high natural water contents and, as an index property, w _L takes no account of the properties or structures of highly heterogeneous intact peat. However, the usual procedure for determining the w _L of peat is not fully standardised. Prepared samples will normally include potentially highly reactive particles of disrupted fibres and wood fragments that would not be present in such freshly disintegrated form in the field. This paper presents results from w _L determinations of peat obtained from the scar margins of three bog failures in northwest Ireland, using four different test procedures including a method involving wet-sieving of the peat to separate the humified <425-μm fraction for testing without incorporating artificially fragmented particles of fibres. The sampled peat was classified as H₈–H₁₀ according to the von Post humification scale. The fibre contents varied between the sites, but the ash contents were <3% in all but one test sample, and bulk densities (dry and field-wet) of the peat from all three sites were almost identical. w _L results from the wet-sieving method were 708–785%, compared with 633–980% from the standard method. The highest measured field water contents exceeded the wet-sieved w _L for all three of the field sites. Tests of cone penetration into intact peat cores demonstrated the influence of the reinforcing effect of in situ fibres. The results strongly suggest the need to adopt a fully standardised procedure for determining the w _L of peat. Additional shear vane measurements of intact and remoulded peat from a bog failure in Northern Ireland indicated a very high ‘strength sensitivity’. This leads to the suggestion that a slight disturbance of basal peat can lead to a loss of strength that rapidly propagates as local stresses change and cause further remoulding as water contents exceed w _L.     

Reaction between liquid iron and (Mg,Fe)SiO3-perovskite and solubilities of Si and O in molten iron at 27 GPa

The Earth’s core contains light elements and their identification is essential for our understanding of the thermal structure and convection in the core that drives the geodynamo and heat flow from the core to the mantle. Solubilities of Si and O in liquid iron coexisting with (Mg,Fe)SiO₃-perovskite, a major constituent of the lower mantle, were investigated at temperatures between 2,320 and 3,040 K at 27 GPa. It was observed that Si dissolved in the liquid iron up to 1.70 wt% at 3,040 K and O dissolved in the liquid iron up to 7.5 wt% at 2,800 K. It was also clearly seen that liquid iron reacts with (Mg,Fe)SiO₃-perovskite to form magnesiowüstite and it contains Si and O at 27 GPa and at 2,640 and 3,040 K. The amounts of Si and O in the liquid iron are 1.70 and 2.25 wt% at 3,040 K, respectively. The solubilities of Si and O in liquid iron coexisting with (Mg,Fe)SiO₃-perovskite have strong positive temperature dependency. Hence, they can be plausible candidates for the light elements in the core.     

山西大同新生代火山岩熔融相平衡的实验研究

通过低压熔融相平衡实验，研究山西大同火山群玄武岩在结晶分离作用过程中液相成分的演化规律，探讨了矿物和溶浆之间元素的分配。在１００ｋＰａ，ｆｏ２＝ＮＮＯ，Ｔ＝１１００°～１３００℃条件下，矿物结晶顺序为Ｏ１→Ｐ１→Ｃｐｘ。橄榄石为液相线矿物。橄榄石－熔体Ｆｅ２－－Ｍｇ２－交换反应的分配系数是一个与温度无关的常数、残余液相线成分取决于晶出矿物相的化学成分及含量。Ｏ１＋ＣｐＸ＋Ｐ１饱和液相成分的Ｏ１－Ｄｉ－Ｓｉｌ和Ｏ１－Ｄｉ－Ｎｅ三元系相图清楚地反映了熔岩低压结晶作用的趋势，低压下熔浆的主要元素变化很大程度上依赖于母岩浆ＳｉＯ２饱和程度。