Performances of Landfill Liners under Dry and Wet Conditions

This paper addresses the study conducted on the performance of landfill liner interface parameters. Interface shear strength parameters for various combinations of 9 different lining materials were studied and presented in this paper. This comprehensive testing program covers the interfaces between: (1) soil and compacted clay liner (CCL), (2) geomembrane (HDPEs or PVC) and soil, (3) geosynthetic clay liner (GCL)/CCL and soil, (4) geomembrane and geotextile, (5) geotextile and soil, (6) geotextile and GCL/CCL, and (7) geomembrane and GCL/CCL. The experiments were conducted for both at dry or optimum moisture condition and at saturated or wet condition. The interface performance under both conditions were compared to access the material performances. Tabulated summaries of interface test data under dry or optimum moisture condition (OMO) and saturated or wet condition are presented in the paper.     

Reproductive biology of Ilisha elongata (Teleostei: Pristigasteridae) in Ariake Sound,Japan: Implications for estuarine fish conservation in Asia

Elongate ilisha (Ilisha enlongata) is a commercially important species that contributes to clupeoid fisheries in Asian countries. In the present study, the reproductive biology of I. elongata in Ariake Sound, Japan is determined for the first time. Six maturity stages were described using ovarian and testicular histology throughout the annual cycle. The spawning season in Ariake Sound lasts from May to July, with peak spawning activity in May and June. Age at first maturity was estimated to be 2 years, with a few exceptions of 1 year in well-developed males. Ovaries that contained both tertiary yolk oocytes and postovulatory follicles occurred from late May to late July, indicating that I. elongata is a multiple spawner. The size–frequency distribution of oocytes provided evidence for its multiple spawning and accuracy of the fecundity estimates. The batch fecundity of this species was estimated at between 22,200 and 270,900 eggs per individual, increasing with age between two and six years. The present findings on the reproductive strategy of I. elongata in Ariake Sound are generally consistent with those in temperate or subtropical populations, but quite different from those of tropical population where first maturation occurs around 200 days and life spans are shorter, with a maximum age less than 3 years. The conservation implications of this reproductive strategy in a harsh, variable environment in Asian countries are also discussed.     

Grain-growth kinetics in wadsleyite: Effects of chemical environment

Grain-growth kinetics in wadsleyite was investigated using a multianvil high-pressure apparatus. Fine-grained wadsleyite aggregates were synthesized by isostatic hot-pressing and were subsequently annealed under high pressure and temperature in a controlled chemical environment. Wadsleyite samples show normal grain-growth characterized by a log-normal grain-size distribution following the relation, where n is a constant, L the grain-size at time t, L₀ the grain-size at time t = 0 and k is a rate constant that depends on temperature T and chemical environments (fO₂: oxygen fugacity in Pa, C_OH: water content in H/10⁶Si) as:

     

Impacts of global warming on hydrological cycles in the Asian monsoon region

The hydrologic changes and the impact of these changes constitute a fundamental global-warmingrelated concern. Faced with threats to human life and natural ecosystems, such as droughts, floods, and soil erosion, water resource planners must increasingly make future risk assessments. Though hydrological predictions associated with the global climate change are already being performed, mainly through the use of GCMs, coarse spatial resolutions and uncertain physical processes limit the representation of terrestrial water/energy interactions and the variability in such systems as the Asian monsoon. Despite numerous studies, the regional responses of hydrologic changes resulting from climate change remains inconclusive. In this paper, an attempt at dynamical downsealing of future hydrologic projection under global climate change in Asia is addressed. The authors conducted present and future Asian regional climate simulations which were nested in the results of Atmospheric General Circulation Model （AGCM） experiments. The regional climate model could capture the general simulated features of the AGCM. Also, some regional phenomena such as orographic precipitation, which did not appear in the outcome of the AGCM simulation, were successfully produced. Under global warming, the increase of water vapor associated with the warmed air temperature was projected. It was projected to bring more abundant water vapor to the southern portions of India and the Bay of Bengal, and to enhance precipitation especially over the mountainous regions, the western part of India and the southern edge of the Tibetan Plateau. As a result of the changes in the synoptic flow patterns and precipitation under global warming, the increases of annual mean precipitation and surface runoff were projected in many regions of Asia. However, both the positive and negative changes of seasonal surface runoff were projected in some regions which will increase the flood risk and cause a mismatch between water demand and water availability in the agricul     

Decomposition of kyanite and solubility of Al2O3 in stishovite at high pressure and high temperature conditions

In order to constrain the high-pressure behavior of kyanite, multi-anvil experiments have been carried out from 15 to 25 GPa, and 1,350 to 2,500°C. Both forward and reversal approaches to phase equilibria were adopted in these experiments. We find that kyanite breaks down to stishovite + corundum at pressures above ∼15 GPa, and stishovite + corundum should be the stable phase assemblage at the pressure–temperature conditions of the transition zone and the uppermost part of the lower mantle of the Earth, in agreement with previous multi-anvil experimental studies and ab initio calculation results, but in disagreement with some of the diamond-anvil cell experimental studies in the literature. The Al₂O₃ solubility in nominally dry stishovite has been tightly bracketed by forward and reversal experiments; it is slightly but consistently reduced by pressure increase. Its response to temperature increase, however, is more complicated: increases at low temperatures, maximizes at around 2,000°C, and perhaps decreases at higher temperatures. Consequently, the Al₂O₃ solubility in dry stishovite at conditions of high temperature–high pressure is very limited.     

Seismological evidence for compositional variations at the base of the mantle transition zone under Japan Islands

Temperature and water content anomalies just above the 660-km discontinuity under the Japan Islands are estimated from seismological observations. Two sets of seismological observations of P-wave velocity perturbations and depth variations of the 660-km discontinuity are used, which are (1) long-wavelength (~ 500 km) variations from seismic tomography based on a grid parameterization and waveform analysis of ScS reverberations and (2) moderate-wavelength (~ 150 km) variations from seismic tomography with a block parameterization and receiver-function analysis. To estimate temperature and water content anomalies, partial derivatives of velocity and depth variations with respect to temperature and water content determined by mineral physics studies are used. Under Southwest Japan, low temperature and high water-content anomalies are obtained from both sets of seismological observations, which have already been found by a previous study. Under Northeast Japan, however, there are discrepancies between the results estimated from the two data sets, possibly due to the different resolution scales. This discrepancy is dismissed when examining distributions of the temperature and water content anomalies. These anomalies can be grouped into two geographical locations, one group under Southwest Japan, the other under Northeast Japan. The two groups are clearly separated and exhibit common features in both sets of the seismological observations. The grouping is interpreted by a compositional difference between the subducting Pacific slab under Southwest Japan and a normal mantle under Northeast Japan.     

Stable Isotopic Information on Calcareous Pelitic Rocks in the Tizapa Volcanogenic Massive Sulfide Deposit Area, the United Mexican States

Abstract: Tizapa volcanogenic massive sulfide (VMS) deposit is hosted in greenschist facies metamorphic rocks; footwall is green schist of felsic to mafic metavolcanic rocks and hanging wall is graphite schist of metasedmentary pelitic rock. Pb-Pb dating of ore samples indicates 103. 4Ma to 156. 3Ma for the age of mineralization (JICA/MMAJ, 1991).     

日本北海道Koryu矿山浅成低温热液Au-Ag矿化的成因

Koryu矿山位于北海道南西部,为一浅成低温热液型Au-Ag石英脉型矿床.矿床产于中新世黑色泥岩中的东西向剪切带内.矿床含有8个主要脉体,总体呈东西走向,在水平、垂直方向上均发生结构、构造的变化.1号脉和3号脉中冰长石K-Ar年龄为0.8~1.2 Ma,表明矿化时代为更新世.根据矿脉体的穿插关系和脉内矿物共生关系得出矿区有2期矿化,早期矿化可分3个阶段（即E-Ⅰ,E-Ⅱ,E-Ⅲ）,晚期矿化可分成7个阶段（即L-Ⅰ,L-Ⅱ,L-Ⅲ,L-Ⅳ,L-Ⅴ,L-Ⅵ,L-Ⅶ）.宽矿脉体由多阶段矿化组成,Au-Ag矿化主要与L-Ⅲ阶段矿化密切相关.早期矿化形成的特征矿物为钙菱镁矿、钙锰辉石及少量矿石矿物;晚期矿化形成大量矿石矿物.含AuAg的矿物主要为银金矿、螺状硫银矿-辉硒银矿、硫锑铜银矿-硫砷铜银矿、浓红银矿-淡红银矿、辉铜银矿、马硫铜银矿、碲银矿和黝铜矿.而脉石矿物为绿泥石、蒙脱石、石英.区内许多成矿阶段均含富气相流体包裹体,这表明沸腾作用在整个过程中间歇发生.早期矿化温度（263~283℃）稍高于晚期矿化温度（246~260℃）.成矿溶液盐度为0.5%~6.0% NaCl当量,尽管CO2含量在晚期矿化阶段达0.4%（质量分数）.这些特征表明成矿流体最大压力为3.1~6.8 M Pa,相当于古潜水面下430~850 m深度.石英形态学结合流体包裹体研究证实流体沸腾作用反复发生,导致SiO2过饱和,形成结构各异的二氧化硅矿物.在脉体形成过程中,SiO2重结晶形成石英.稳定同位素资料、矿物共生组合特征、石英结构特征和流体包裹体特征综合研究得出Koryu金-银矿床成矿模式如下：矿床矿化分为明显的两期,即早期和晚期,分别对应类型1和类型2两种热液流体.早期流体具相对高的W18O值（-5.3‰~-4.7‰）,温度不低于260℃;晚期流体W18O值相对偏低（-9.3‰~-6.0‰）,温度250℃以上.类型1流体发生深部循环,淋滤Ca和M n元素,在早期矿化过程中形成钙菱镁矿、钙锰辉石.与浅成水混合的类型2流体沿新通道上升,富含Au、Ag元素.在晚期矿化过程中,流体上升至沸腾带（ < 850 m）,金、银在250℃沉淀成矿.     

Probabilistic estimates of recent changes in temperature: a multi-scale attribution analysis

The role of anthropogenic forcings in temperature changes during recent decades is investigated over a range of spatial scales. Changes in the annual mean surface temperature and also in the warmest night of the year, which has implications for human health, are considered. Distributions of regional trends with and without the effect of human activity are produced, using constraints from a global optimal detection analysis. Anthropogenic forcings are estimated to have more than doubled the likelihood of mean warming in all regions considered except central North America, where results are more model dependent. The likelihood of warming of the warmest night has also increased, but the estimated change is more uncertain. Inferences on sub-continental scales are indicative rather than definitive because of the absence of locally important forcings and processes in model simulations, as well as model biases. As model inconsistencies may impact regional analyses, a multi-model approach is essential.