Forecasting ecologically hazardous phenomena resulting from the impounding of swamps by the Boguchany reservoir

A forecast is made for ecologically hazardous phenomena: peat rising to the surface to form peat islands, their influence on navigation on the Angara river, appearance of peat crumbs, and water quality impairment resulting from the impounding of swamps by the Boguchany reservoir.     

Climate and carbon cycle variations in the 20th and 21st centuries in a model of intermediate complexity

The climate model of intermediate complexity developed at the Oboukhov Institute of Atmospheric Physics, Russian Academy of Sciences (IAP RAS CM), has been supplemented by a zero-dimensional carbon cycle model. With the carbon dioxide emissions prescribed for the second half of the 19th century and for the 20th century, the model satisfactorily reproduces characteristics of the carbon cycle over this period. However, with continued anthropogenic CO₂ emissions (SRES scenarios A1B, A2, B1, and B2), the climate-carbon cycle feedback in the model leads to an additional atmospheric CO₂ increase (in comparison with the case where the influence of climate changes on the carbon exchange between the atmosphere and the underlying surface is disregarded). This additional increase is varied in the range 67–90 ppmv depending on the scenario and is mainly due to the dynamics of soil carbon storage. The climate-carbon cycle feedback parameter varies nonmonotonically with time. Positions of its extremes separate characteristic periods of the change in the intensity of anthropogenic emissions and of climate variations. By the end of the 21st century, depending on the emission scenario, the carbon dioxide concentration is expected to increase to 615–875 ppmv and the global temperature will rise by 2.4–3.4 K relative to the preindustrial value. In the 20th–21st centuries, a general growth of the buildup of carbon dioxide in the atmosphere and ocean and its reduction in terrestrial ecosystems can be expected. In general, by the end of the 21st century, the more aggressive emission scenarios are characterized by a smaller climate-carbon cycle feedback parameter, a lower sensitivity of climate to a single increase in the atmospheric concentration of carbon dioxide, a larger fraction of anthropogenic emissions stored in the atmosphere and the ocean, and a smaller fraction of emissions in terrestrial ecosystems.     

Mariinskite, BeCr2O4, a new mineral, chromium analog of chrysoberyl

A new mineral, mariinskite, BeCr₂O₄, the chromium analog of chrysoberyl, has been found at the Mariinsky (Malyshevo) deposit, the Ural Emerald Mines, the Central Urals, Russia. The mineral is named after its type locality. It was discovered in chromitite in association with fluorphlogopite, Cr-bearing muscovite, eskolaite, and tourmaline. Mariinskite occurs as anhedral grains ranging from 0.01 to 0.3 mm in size; in some cases it forms pseudohexagonal chrysoberyl-type twins. The mineral is dark-green, with a pale green streak; the Mohs’ hardness is 8.5, microhardness VHN = 1725 kg/mm². D _meas = 4.25(2) g/cm³, D _calc = 4.25 g/cm³. Microscopically, it is emerald-green, pleochroic from emerald-green (γ) to yellow-green (β) and greenish yellow (α). The new mineral is biaxial (+), γ = 2.15(1), β = 2.09(3), and α = 2.05(1), 2V _meas = 80 ± (10)°, 2V _calc = 80.5°. In reflected light, it is gray with green reflections; R _max (589) = 12.9%; R _min (589) = 12.3%, and there are strong, internal green reflections. The strongest absorption bands in the IR spectrum are as follows (cm^?1): 935, 700, 614, 534. Space group Pnma, a = 9.727(3), b = 5.619(1), c = 4.499(1) Å, V = 245.9(3) ų, Z = 4. The strongest reflections in the X-ray powder diffraction pattern are as follows (d Å, I, hkl): 4.08(40)(101), 3.31(90)(111), 2.629(50)(301), 2.434(50)(220), 2.381(40)(311), 2.139(60)(221), 1.651(100)(222). The average chemical composition of mariinskite (electron microprobe, wt %) is as follows: BeO 16.3, Al₂O₃ 23.89, Cr₂O₃ 58.67, Fe₂O₃ 0.26, V₂O₃ 0.26, TiO₂ 0.61, total is 99.98. The empirical formula, calculated on the basis of four O atoms is Be_1.03(Cr_1.22Al_0.74Ti_0.01Fe_0.01V_0.01)_1.99O₄. The compatibility index 1 ? (K_p/K_c), 0.019, is excellent. The type specimens are deposited in the Fersman Mineralogical Museum, Russian Academy of Sciences, Moscow, and the Ural Geological Museum, Yekaterinburg, Russia.     

Discovery of low aluminium nevadaite from the Kara-Chagyr Area,Kyrgyzstan

The rare phosphate—nevadaite has been found at Kara-Chagyr (Batken region, Kyrgyzstan) in a zone of alteration of vanadium bearing “black shales”. It occurs as blue crusts of spherulitic aggregates of tiny tabular crystals (0.1–10 μm). It is associated with metahewettite, hummerite, carnotite, minyulite, fluellite, crandallite, variscite, and woodhouseite. Optical properties: n = 1.542–1.555, D _meas (for aggregates) = 2.58(1) g/cm³, D _calc = 2.582 g/cm³. The most intense X-ray powder reflections are as follows: [d/n, Å, (I _meas), (hkl)]: 9.54 (80) (020), 6.03 (100) (200), 5.61 (100) (130), 3.91 (60) (310), 3.41 (80) (041), 2.982 (100) (241), 2.804 (60) (331), 2.672 (70) (061), 1.845 (60) (352) 1.507 (70) (243). Calculated cell dimensions are: a = 12.072(10) Å, b = 18.958(15) Å, c = 4.969(5) Å, α = β = γ = 90°, V = 1137.2 ų. Electron microprobe analyses gives (wt %): (observed (average of 8 analyses); (calculated for 22H₂O)): P₂O₅ 34.69 (31.85), SiO₂ 0.25 (0.24), Al₂O₃ 25.61 (23.50), V₂O 5.58 (5.13), Fe₂O₃ 0.48 (0.46), MnO 0.03 (0.03), CuO 10.79 (9.90), ZnO 0.69 (0.65), CaO 0.18 (0.15), MgO 0.17 (0.17), K₂O 0.08 (0.08), F 7.40 (6.79), H₂O 17.16 (by diff.) (23.90), ?F₂ =O \(\bar 3\).11 (\(\bar 2\).86), total 100.00 (100.00).The crystal-chemical formula of the mineral is (Cu _2.2 ⁺² □_2.03V _1.21 ⁺³ Al_0.15Zn_0.14Fe_0.10Mg_0.07Ca_0.05K_0.03Mn_0.01)_6.00(Al_8.00(P_7.93Si_0.07O₃₂)F_6.32(OH)_2.98 · 22(H₂O) for the ideal number of water molecules. Nevadaite from Kara-Chagyr differs from that from the type locality, Gold Quarry (Nev., USA), by its lower Al content. The IR-spectrum, and microphotographs of nevadaite and associated minerals are given.