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1.
New geologic mapping of the area near Castellamonte (Torino Province) describes a wide Plio-Quaternary continental succession, up to about 100-m thick. This sequence is distinguished according to allostratigraphic criteria. Altitude, degree of pedogenesis and sediment supply from different basins are also used. Within a single alloformation, several lithofacies are described.Fine-grained fan-delta sediments (Vespia Alloformation) are described in the lower part of the continental succession. The fossil plant remains indicate an Early–Middle Pliocene age. These sediments show an evident deformation and fill ancient lacustrine basins, likely associated with the Canavese Line trend. Their wide distribution and considerable thickness suggest subsidence.Coarse-grained glacial, outwash and fluvial sediments (Colleretto Castelnuovo, S. Defendente, Case Musso, Pagliero, Serra and Piverone Alloformations) are described in the upper part of the continental succession. They consist of undeformed sediments deposited during Middle to Late Pleistocene. These sediments indicate the presence of small local glaciers along the current valley trends. The terracing ratios among the different units and their small thicknesses indicate subsequent differential uplift.  相似文献   
2.
Marbles from the Pohorje area in Slovenia are investigated by mineralogical-petrographical analyses of thin sections as well as by cathodoluminescence in order to detect their local variability in texture and mineral assemblages. The CL colours observed in a cold cathode device are related to the manganese contents. An attempt is made to relate the textures seen under CL to mineral reactions during the process of metamorphism. The predominantly calcite marbles from Pohorje exhibit orange luminescence with some dolomite lenses with red luminescence. The typical mineral assemblages are calcite+tremolite+phlogopite or calcite+dolomite+tremolite+phlogopite. Therefore, the estimated temperature from the stability of mineral assemblage is assumed at approximately 500 °C.  相似文献   
3.
Polycyclic aromatic hydrocarbons (PAHs) are widespread carcinogenic, mutagenic and teratogenic pollutants that can significantly affect ecosystems and exert an influence on marine planktonic and benthic communities as well as on higher organisms such as fish and mammals, including humans. In this paper the concentrations of six PAHs in water, seston and copepods were examined in a harbour zone of the Genova Gulf (Ligurian Sea) from November 1997 to June 1998. The importance of freshwater inputs coming from a polluted stream and the influence of seasonal and atmospheric factors were also considered. Highest PAH values were recorded during spring. Fluoranthene, Benzo[b]fluoranthene and Benzo[k]fluoranthene were the most abundant PAHs either in water, seston or copepods. The concentration of total PAHs in seawater was often lower than the detection limit: recorded values ranged between 0.001 and 0.06 ppb. In seston, total PAHs ranged between 0.033 and 6.26 ng·g?1 and in copepods between 0.01 and 2.34 ng·g?1. With this study, PAH contamination in the harbour zone of Genova Sestri‐Ponente and the importance of inputs of organic pollutants coming from land and freshwaters have been emphasized.  相似文献   
4.
5.
Increased atmospheric carbon dioxide concentration provided warmer atmospheric temperature and higher atmospheric water vapor content, but not necessarily more precipitation. A set of experiments performed with a state-of-the-art coupled general circulation model forced with increased atmospheric CO2 concentration (2, 4 and 16 times the present-day mean value) were analyzed and compared with a control experiment to evaluate the effect of increased CO2 levels on monsoons. Generally, the monsoon precipitation responses to CO2 forcing are largest if extreme concentrations of carbon dioxide are used, but they are not necessarly proportional to the forcing applied. In fact, despite a common response in terms of an atmospheric water vapor increase to the atmospheric warming, two out of the six monsoons studied simulate less or equal summer mean precipitation in the 16×CO2 experiment compared to the intermediate sensitivity experiments. The precipitation differences between CO2 sensitivity experiments and CTRL have been investigated specifying the contribution of thermodynamic and purely dynamic processes. As a general rule, the differences depending on the atmospheric moisture content changes (thermodynamic component) are large and positive, and they tend to be damped by the dynamic component associated with the changes in the vertical velocity. However, differences are observed among monsoons in terms of the role played by other terms (like moisture advection and evaporation) in shaping the precipitation changes in warmer climates. The precipitation increase, even if weak, occurs despite a weakening of the mean circulation in the monsoon regions (??precipitation-wind paradox??). In particular, the tropical east-west Walker circulation is reduced, as found from velocity potential analysis. The meridional component of the monsoon circulation is changed as well, with larger (smaller) meridional (vertical) scales.  相似文献   
6.
After completion of an exploration well, sandstones of the Exter Formation were hydraulically tested to determine the hydraulic properties and to evaluate chemical and microbial processes caused by drilling and water production. The aim was to determine the suitability of the formation as a reservoir for aquifer thermal energy storage. The tests revealed a hydraulic conductivity of 1–2 E-5 m/s of the reservoir, resulting in a productivity index of 0.6–1 m3/h/bar. A hydraulic connection of the Exter Formation to the overlaying, artesian “Rupelbasissand” cannot be excluded. Water samples were collected for chemical and microbiological analyses. The water was similarly composed as sea water with a maximum salinity of 24.9 g/L, dominated by NaCl (15.6 g/L Cl and 7.8 g/L Na). Until the end of the tests, the water was affected by drilling mud as indicated by the high pH (8.9) and high bicarbonate concentration (359 mg/L) that both resulted from the impact of sodium carbonate (Na2CO3) additives. The high amount of dissolved organic matter (>?58 mg/L) and its molecular-weight distribution pattern indicated that residues of cellulose, an ingredient of the drilling mud, were still present at the end of the tests. Clear evidence of this contamination gave the measured uranine that was added as a tracer into the drilling mud. During fluid production, the microbial community structure and abundance changed and correlated with the content of drilling mud. Eight taxa of sulfate-reducing bacteria, key organisms in processes like bio-corrosion and bio-clogging, were identified. It can be assumed that their activity will be affected during usage of the reservoir.  相似文献   
7.
Metallothionein has been assayed in a range of aquatic animal tissues as an indicator of metal exposure. We sequenced chub (Leuciscus cephalus) metallothionein cDNA which showed over 90% homology to common carp, goldfish and stone loach and 77% homology to rainbow trout sequences for metallothionein. We then used the extended primer method to develop an accurate quantitative competitive RT-PCR assay for metallothionein mRNA. RT-PCR was used to measure metallothionein mRNA in feral chub from a range of field sites, with different levels of heavy metal pollution, in the West Midlands, UK. Measurements were complemented by analysis of liver and gill metallothionein protein by capillary electrophoresis. There was no significant difference in the metallothionein protein levels between fish of different rivers and there was no evidence of elevation of mRNA at the sites of highest metal exposure. The level of metal exposure (e.g. zinc, nickel and cadmium each ranging between 15 and 28 microg/l ) at the pH (7.5-8.5) of these rivers appears insufficient to elevate hepatic or gill metallothionein in chub. A lack of elevation of hepatic metallothionein mRNA in chub exposed to zinc, copper and manganese for 24 h and 10 days in the laboratory also suggests a non-responsiveness of this species.  相似文献   
8.
The current detailed chronostratigraphic framework of the last 1 Ma of an eastern Mediterranean sequence (Haifa Bay, Israel) aims to examine the relative roles of sea‐level changes, climate and tectonics. Seven continuous marine cores, up to ~120 m long, were recovered from shallow water depths. The cores were dated by optically stimulated luminescence, 14C, magnetostratigraphy, 230Th/234U, 26Al/10Be, occurrence of index fossils and correlated to the global sea‐level curve and Marine Isotope Stages (MIS). The sedimentary sequence accumulated during the last ca. 1.0 Ma consists of 21 transgression–regression units with hiatuses between them. Five marine/terrestrial cycles, which occur in the lower part of the sequence, are attributed to the Jaramillo subchron and the Brunhes–Matuyama boundary, and correspond to MIS 29–21. The top ~50 m includes three sedimentary cycles deposited in the last ca. 400 ka. The regressive phases during this interval correspond to Glacial MIS 8, 6 and 2, while the transgressions correspond to Interglacial MIS 11, 7, 5 and 1. Thus, for the first time, this study documents the longest Quaternary succession dated so far in a key area of the Levant, sensitive to global history of sea‐level changes and glacial/interglacial fluctuations. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
9.
The name Calabrian was introduced in the geological literature by the French stratigrapher Maurice Gignoux in 1910, and later described in his important monograph (633 pages) "Les formations marines pliocknes et quaternaires de l'ltalie du sud et de la Sicile "published in 1913. Detailed data were provided on several sections (Santa Maria di Catanzaro, Caraffa, Monasterace, Palermo) and on their fossil content. The Calabrian Stage has commonly been used for over fifty years as the oldest subdivision of the Qua- ternary, notably in the time scales of Berggren & van Cou- vering (1974) and Haq & Eysinga (1987). However, after the GSSP for the Pliocene/Pleistocene boundary (P/P) was approved by INQUA in 1982 and ratified by lUGS in 1984 at the Vrica section of Calabria, there was a decline in the usage of the stage name, and an increasing tendency by many Quaternary workers to question the boundary stratotype. This was because there was increasing evidence that it did not correspond to the beginning of the "ice age". In doing so, they were not complying with the recommendations presented at the 18th International Geological Congress (IGC) in London, 1948 (Oakley, 1950).  相似文献   
10.
The new mineral sardignaite, a bismuth molybdate with formula BiMo2O7(OH)·2H2O, occurs in quartz veins within a granitic rock at Su Senargiu, near Sarroch, Sardegna, Italy. The name is after the locality. Sardignaite occurs a thin prismatic crystals up to 1 mm in length, with pale yellow color and a white streak. It is transparent with adamantine lustre, non fluorescent, and brittle with a conchoidal fracture. It is associated with bismuthinite, bismoclite, molybdenite, ferrimolybdite, koechlinite, wulfenite, and the new mineral IMA 2009–022. Mohs hardness is ca. 3. D calc is 4.82 g/cm3. The mineral is monoclinic, space group P21/m, with a 5.7797(7), b 11.567(1), c 6.3344(8) Å, β 113.360(9)°, V 388.8(1) Å3. The strongest lines in the powder X-ray diffraction pattern are d(I)(hkl): 3.206(100)(031), 5.03(80)(?101), 1.992(45)(221), 3.120(32)(130). The crystal structure of sardignaite was solved to R(F) 0.056 using single-crystal X-ray diffraction data, and is characterized by edge-sharing dimers of [MoO5(H2O)] octahedra, linked to each other through corner-sharing to give rise to corrugated columns running along b. Such columns are held together by Bi3+ cations, eight-fold coordinated by 7 O + 1 (OH). Both the mineral and its name were approved by the IMA-CNMNC.  相似文献   
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