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Disposal of acid gas, composed of carbon dioxide (CO2) and hydrogen sulfide (H2S), in deep underground formations is a means for reducing atmospheric emissions of toxic and greenhouse gases produced from sour-gas reservoirs that has been practiced for 18 years in North America and is currently being considered in other regions, such as the Middle East and central Asia. Acid-gas-injection operations constitute a commercial-scale analog to CO2 injection in geological media as a climate-change mitigation measure. Deep saline aquifers provide a very large capacity for the sequestration of acid and greenhouse gases, being found in all sedimentary basins around the world. Proper understanding of the relative permeability-displacement character of such systems is essential in ascertaining gas injectivity and migration, and in assessing the suitability, containment, and safety of prospective injection sites. Pure CO2 and H2S represent the compositional end members of acid and greenhouse gases, hence the interest in measuring their displacement properties. This paper presents the detailed experimental equipment and protocols along with the results of a series of relative permeability measurements conducted at full reservoir conditions using supercritical pure CO2 and H2S on samples of intercrystalline sandstone, carbonate, shale, and anhydrite rocks from the Wabamun and Zama areas in Alberta, Canada, where large CO2 sources and several acid-gas-injection operations exist. Results of the relative permeability measurements are presented for each fluid and rock type. The results provide a valuable data set for the evaluation and simulation of acid-gas disposal and CO2-sequestration projects. [ABSTRACT FROM AUTHOR]

This study investigates the environmental efficiency, productivity, and shadow price of carbon dioxide (CO 2) emissions of 52 Belt and Road Initiative (BRI) countries for 2005–2016. We consider the case of three inputs (Energy, Labor and Capital), one desirable output (GDP), and one undesirable output (CO 2 emissions). The contribution of this paper is that we use the endogenous directional distance function (DDF) to construct environmental efficiency and sequential productivity indicators. The benefit of this approach is that we can both avoid the influence of arbitrary mapping rules and capture the progressive nature of the technology. The results show that the technical efficiency of Eastern Asia increased continuously during the sample period, while those of the other regions did not show a significant trend, indicating that Eastern Asia was catching up with the frontier faster than the rest of the regions. The average shadow prices of CO 2 emissions for all the BRI countries increased steadily over the sample period, but the shadow prices of Eastern Europe and Central Asia are much higher than those of the other regions. The average productivity of the BRI countries improved for most periods, mainly because of technological progress. Moreover, the technical changes for the six regions during the sample period are all positive, meaning that technology progress is universal for the BRI countries, especially for those in Eastern Asia. The results of this study have important policy implications for carbon reduction in the BRI countries. • The technical efficiency of Eastern Asia increased continuously during 2005–2016. • The reduction potential of CO2 emissions for BRI countries is substantial. • The discrepancy between inefficient BRI countries and their efficient counterparts has increased. • The average shadow price of CO2 emissions for BRI countries has increased during 2005–2016. [ABSTRACT FROM AUTHOR]

By investigating temperature and precipitation data from eight meteorological stations in the Syr Darya Basin (SDB) during 1881-2011 and 1891-2011, we analyzed trends using the Mann-Kendall (MK) test. Our results indicated that there was a notable increasing trend in annual temperature of 0.14 °C/decade ( P < 0.05) and step change points in 1989 ( P < 0.05). Similarly, annual precipitation showed a significant rising trend ( P < 0.001) at a rate of 4.44 mm/decade and step change points in 1991 ( P < 0.05). Overall, temperature and precipitation increases were more rapid in the plains than in the mountain areas. Furthermore, we found that temperature in the SDB region is strongly associated with the Asian Polar Vortex Area Index (APVAI, correlation coefficient: R = −0.701, P < 0.01) rather than with carbon dioxide emissions, especially in the plains area. For precipitation, the correlation coefficient is strongly associated with the Tibet Plateau Index (TPI, R = 0.490, P < 0.01), followed by the Antarctic Oscillation Index (AAOI, R = 0.343, P < 0.01), and the correlations in the plains are higher than those in the mountains. It is anticipated that the results of this study will further the understanding surrounding climate change in the SDB. [ABSTRACT FROM AUTHOR]

Data on melt inclusions in minerals provide direct information on the physicochemical petrogenetic parameters of Late Cenozoic basaltic complexes in the Southern Baikal and Southern Khangai Volcanic Areas (SBVA and SKVA, respectively) in Central Asia. Newly obtained data on inclusions in olivine reveal differences between the temperatures of the magmatic systems that produced basalts in SBVA and SKVA. The comparison of the experimentally determined homogenization temperatures and parameters calculated from data on the composition of glasses in the melt inclusions allowed us to realistically evaluate the temperatures of the petrogenetic processes that generated Late Cenozoic basaltic complexes in SBVA (1130-1160°C and 1175-1250°C) and SKVA (1145-1185°C, 1210-1270, and about 1300-1310°C). The analysis of fluid phases in the inclusions testifies that basaltic melts in SBVA were rich in carbon dioxide, which ensured elevated pressures (up to 5-6.6 kbar) during the crystallization of the minerals. Data on the composition of inclusions in the olivine highlight differences between the chemistries of magmatic systems in the two territories: elevated TiO, AlO, and CaO concentrations at relatively low FeO and MgO contents in the SBVA melts as compared to analogous concentrations in the SKVA basaltic magmas. The petrochemical and geochemical parameters of the primary melt inclusions and the composition of the olivine generally testify that deep plume magmatic processes were actively involved in the generation of basalts in both SBVA and SKVA. Data on melt inclusions in olivine and the composition of the clinopyroxene reveal similarities between the geochemistry, mineralogy, and crystallization parameters of Late Cenozoic basalts in both SBVA and SKVA and Cretaceous-Paleogene basalts in the Tien Shan and their certain differences from the plume-related systems of the OIB type. These data suggest that the geodynamic environment of the Cenozoic and Late Mesozoic intraplate plume magmatism in Central Asia were different from the geodynamic environment of typical long-lived mantle plumes like that at Hawaii. [ABSTRACT FROM AUTHOR]