Variation Trend and Characteristics of Anthropogenic CO Column Content in the Atmosphere over Beijing and Moscow          下载免费PDF全文

WANG Pu-Cai  Georgy S.GOLITSYN  WANG Geng-Chen  Evgeny I.GRECHKO  Vadim S.RAKITIN  Ekaterina V.FOKEEVA  Anatoly V.DZHOLA 《大气和海洋科学快报》2014,(3):243-247

The anthropogenic CO column content in the atmosphere is derived from measurements with infrared grating spectrometers in Beijing, China, and Moscow, Russia, during 1992-2012. Some specific variation char- acteristics and long-term variation trends of the CO col- umn content in the atmosphere in these regions are dis- cussed. An evident variation trend of anthropogenic CO in the atmosphere for the Beijing region is not observed during 1992-2012, while for the Moscow region, it de- creases yearly by about 1.4% for the same period. High CO concentrations appear quite frequently in Beijing, but much less frequently in Moscow, except during the natu- ral fire events in summer 2010. From back trajectory analysis, the high CO concentration observed in Beijing can be attributed to the intensive CO emission sources in its surrounding areas.  相似文献   

The Oka Belt (Southern Siberia and Northern Mongolia): A Neoproterozoic analog of the Japanese Shimanto Belt?     

Alexander  Kuzmichev  Evgeny  Sklyarov  Anatoly  Postnikov  Elena  Bibikova 《Island Arc》2007,16(2):224-242

Abstract   The Oka Belt, composed of clastic rocks and greenschists, extends for approximately 600 km in the South-Siberian Sayan region and adjacent northern Mongolia. For a long time the Oka Belt's age and tectonic setting were the most controversial problem in the region. We argue that the belt was formed in Late Neoproterozoic as an accretionary prism. The Oka Belt shows imbricated thrust structure, which had originally seaward vergence and reflected the Neoproterozoic accretion process. The Early Paleozoic orogeny had minor effect on its structural style. The belt contains tectonic slivers of mid-ocean ridge basalts, some oceanic-island basalts and possible pelagic sediments. In several localities they are associated with gabbro and serpentinite. All these rocks represent the oceanic lithosphere subducting beneath the Oka prism and trapped within it. In the inner zone of the Oka Belt are the blueschists exhumed from the deeper prism level. The northern Oka Belt includes mafic intrusions geochemically similar to normal mid-oceanic ridge basalt and felsic volcaniclastic rocks. This segment of the belt is very similar to the Tertiary portion of northern Shimanto Belt, in Japan, and has also experienced the subduction of orthogonal oceanic ridge beneath the prism. This event dates back to 753 ± 16 Ma (the U-Pb zircon discordia). The Oka prism started accreting in Mid-Neoproterozoic after the subduction had initiated under the Japan-like South-Siberian continental terrain. The prism existed through the second half of Neoproterozoic and accumulated a huge volume of sialic material to enlarge the nearby continent. Currently, the Oka Belt remains poorly studied and is very promising for further investigation and discoveries.  相似文献   

Dynamics of Russian Forests and the Carbon Budget in 1961–1998: An Assessment Based on Long-Term Forest Inventory Data     

Anatoly Shvidenko  Sten Nilsson 《Climatic change》2002,55(1-2):5-37

Development trends of Russian forests and their impact on the global carbon budget were assessed at the national level on the basis of long-term forest inventory data (1961–1998). Over this period, vegetation of Russian forest lands are estimated as a carbon sink, with an annual average level of carbon sequestration in vegetational organic matter of 210 ± 30 Tg C · yr^–1 (soil carbon is not considered in this study), of which 153 Tg C · yr^–1 were accumulated in live biomass and 57 Tg C · yr^–1 in dead wood. The temporal variability of the sink is very large; for the five-year averages used in the analysis, the C sequestration varies from about 60 to above 300 Tg C· yr^–1. It is shown that long-term forest inventory data could serve as an important information base for assessing crucial indicators of full carbon accounting of forests.  相似文献   

Sr and Nd isotope data of apatite,calcite and dolomite as indicators of source,and the relationships of phoscorites and carbonatites from the Kovdor massif,Kola peninsula,Russia   总被引：9，自引：0，他引：9  

Anatoly Zaitsev  Keith Bell 《Contributions to Mineralogy and Petrology》1995,121(3):324-335

A detailed Sr−Nd isotopic study of primary apatite, calcite and dolomite from phoscorites and carbonatites of the Kovdor massif (380 Ma), Kola peninsula, Russia, reveals a complicated evolutionary history. At least six types of phoscorites and five types of carbonatite have been identified from Kovdor by previous investigators based on relative ages and their major and accessory minerals. Isotopic data from apatite define at least two distinct groups of phoscorite and carbonatite. Apatite from the earlier phoscorites and carbonatites (group 1) are characterized by relatively low⁸⁷Sr/⁸⁶Sr (0.70330–0.70349) and¹⁴³Nd/¹⁴⁴Nd initial ratios (0.51230–0.51240) with F=2.01–2.23 wt%, Sr=2185–2975 ppm, Nd=275–660 ppm and Sm=31.7–96.2 ppm. Apatite from the second group has higher⁸⁷Sr/⁸⁶Sr (0.70350–0.70363) and¹⁴³Nd/¹⁴⁴Nd initial ratios (0.51240–0.51247) and higher F (2.63–3.16 wt%), Sr (4790–7500 ppm), Nd (457–1074 ppm) and Sm (68.7–147.6 ppm) contents. This group corresponds to the later phoscorites and carbonatites. One apatite sample from a carbonatite from the earlier group fits into neither of the two groups and is characterized by the highest initial⁸⁷Sr/⁸⁶Sr (0.70385) and lowest¹⁴³Nd/¹⁴⁴Nd (0.51229) of any of the apatites. Within both groups initial⁸⁷Sr/⁸⁶Sr and¹⁴³Nd/¹⁴⁴Nd ratios show negative correlations. Strontium isotope data from coexisting calcite and dolomite support the findings from the apatite study. The Sr and Nd isotopic similarities between carbonatites and phoscorites indicate a genetic relationship between the two rock types. Wide variations in Sr and Nd isotopic composition within some of the earlier carbonatites indicate several distinct intrusive phases. Oxygen isotopic data from calcite and dolomite (δ¹⁸O=+7.2 to +7.7‰ SMOW) indicate the absence of any low-temerature secondary processes in phoscorites and carbonatites, and are consistent with a mantle origin for their parental melts. Apatite data from both groups of phoscorite plot in the depleted quadrant of an ε_Nd versus ε_Sr diagram. Data for the earlier group lie along the Kola Carbonatite Line (KCL) as defined by Kramm (1993) and data from the later group plot above the KCL. The evolution of the phoscorites and carbonatites cannot be explained by simple magmatic differentiation assuming closed system conditions. The Sr−Nd data can best be explained by the mixing of three components. Two of these are similar to the end-members that define the Kola Carbonatite Line and these were involved in the genesis of the early phoscorites and carbonatites. An additional component is needed to explain the isotopic characteristics of the later group. Our study shows that apatite from rocks of different mineralogy and age is ideal for placing constraints on mantle sources and for monitoring the Sr−Nd evolution of carbonatites. Editorial responsibility: W. Schreyer  相似文献   

Barite from the Saf’yanovka VMS deposit (Central Urals) and Semenov-1 and Semenov-3 hydrothermal sulfide fields (Mid-Atlantic Ridge): a comparative analysis of formation conditions     

Nataliya P. Safina  Irina Yu. Melekestseva  Paolo Nimis  Nataliya N. Ankusheva  Anatoly M. Yuminov  Vasily A. Kotlyarov  Sergey A. Sadykov 《Mineralium Deposita》2016,51(4):491-507

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IR-OSL dating of uranium-rich deposits from the new late Pleistocene section at the Voka site, North-Eastern Estonia   总被引：1，自引：0，他引：1  

Anatoly Molodkov   《Quaternary Geochronology》2007,2(1-4):208-215

This paper presents a series of results obtained from the 22 m thick deposits of the late Pleistocene section at the Voka site, NE Estonia. The section has been intensively studied during the past few years to elucidate the dynamics of the late Weichselian palaeoenvironmental changes in the Baltic region. According to the results obtained, the sediments at the Voka site were deposited in presumably freshwater sedimentary basin, which existed at least during the whole pre-Late Glacial Maximum (LGM) period of late Pleistocene (MIS 5 to 3). One of the characteristic features of the deposits is the high uranium content (up to 23 ppm) in the upper part of the section studied. This study aimed to focus on the influence of potentially unstable environmental radioactivity on dosimetric dating results due to possible disequilibrium in the U decay chain. It was found that despite the high uranium content in the deposits, the dispersion of the dates obtained is surprisingly low. At the depths with the highest uranium content, only a moderate increase of the dispersion of the ages is observed.  相似文献   

Post-mortem transport of freshwater mollusc shells in the northern Caspian Sea: A cautionary note on the implications for palaeoecological reconstructions     

Anatoly G. Tarasov  Sophia Z. Kazantseva 《International Journal of Salt Lake Research》1994,3(1):49-52

Fossils of stenohaline taxa are frequently used in palaeoecological and archaeological investigations to indicate the former position of deltas or the occurrence of freshwater conditions. However, the post-mortem transport of freshwater mollusc shells from deltaic and other areas can complicate interpretation of fossil assemblages. We present an example from the north Caspian Sea that shows that failure to consider these taphonomic processes can lead to erroneous conclusions.  相似文献   

Paleomagnetism of Khatyrka and Maynitsky superterranes, Koryak highlands, far eastern Russia     

Alexi Didenko  William Harbert  Anatoly Stavsky 《Tectonophysics》1993,220(1-4):141-155

We have completed a paleomagnetic reconnaissance study of sedimentary and volcanic extrusive rocks collected from two major tectonic zones in northeastern Russia. Paleomagnetic sites were sampled within the fault-bounded structural units of the Khatyrka and Maynitsky superterranes and an overlap sequence of the Khatyrka superterrane. These sampling localities were chosen to allow both within-site and between-site fold tests. Stepwise thermal demagnetization within the temperature range 200–640°C showed a characteristic linear demagnetization path between thermal demagnetization steps of 400°C and 530°C. For thermal steps above 550°C, the magnetic intensity of many samples began to increase rapidly with magnetic directions, which were random between heating steps, suggesting the formation of new magnetic phases in these samples. Paleomagnetic samples collected from basalts and sediments of the Khatyrka superterrane and basalts and gabbros of the Maynitsky superterrane pass fold tests and show significant poleward motion of these superterranes since the formation of their rocks. The observed paleomagnetic paleolatitudes between 24°N or S and 32°N or S can be compared with expected paleolatitudes of 57°N to 79°N. Paleomagnetic results from sites collected from overlapping Senonian rocks pass a fold test at the 99% confidence level and give a pole position not significantly different from that expected from the apparent polar wander path for the Eurasia or North America plates, suggesting that these sedimentary units overlapping the Khatyrka superterrane were deposited along the ancient northeast margin of the Eurasian plate. The declination, in stratigraphie coordinates, shows a maximum clockwise rotation of about 20° when compared with the Eurasian APWP.  相似文献   

Survey of Geomagnetic Observations Made in the Northern Sector of Russia and New Methods for Analysing Them     

Alexei Gvishiani  Renata Lukianova  Anatoly Soloviev  Andrei Khokhlov 《Surveys in Geophysics》2014,35(5):1123-1154

An overview of the geomagnetic observations made in the northern part of Russia is presented from a historical perspective. Several stations were deployed on the territory of the former Soviet Union during the International Geophysical Year, 1957–1958, with the active participation and guidance of the Interagency Geophysical Committee which is inherited by the Geophysical Center of the Russian Academy of Sciences (GC RAS). In the 1990s, the majority of these stations, especially those in the remoter regions, were closed. Nowadays, the geomagnetic network, including the observatories of the INTERMAGNET program, has been restored. Examples of high-latitude geomagnetic variations in the Russian longitudinal sector are shown, and maps and trends of the secular variation over the territory of Russia presented. Particular attention is paid to the automated processing of data and to the analysis methods used. To process the growing amount of high-resolution geomagnetic data, sophisticated mathematical methods based on the fuzzy logic approach and new discrete mathematical analysis algorithms have been developed. The formal methods and algorithms for recognizing both artificial and natural disturbances in the magnetograms are described.  相似文献   

Constraining groundwater modeling with magnetic resonance soundings     

Boucher M  Favreau G  Nazoumou Y  Cappelaere B  Massuel S  Legchenko A 《Ground water》2012,50(5):775-784

Magnetic resonance sounding (MRS) is a noninvasive geophysical method that allows estimating the free water content and transmissivity of aquifers. In this article, the ability of MRS to improve the reliability of a numerical groundwater model is assessed. Thirty-five sites were investigated by MRS over a ～5000 km(2) domain of the sedimentary Continental Terminal aquifer in SW Niger. Time domain electromagnetic soundings were jointly carried out to estimate the aquifer thickness. A groundwater model was previously built for this section of the aquifer and forced by the outputs from a distributed surface hydrology model, to simulate the observed long-term (1992 to 2003) rise in the water table. Uncertainty analysis had shown that independent estimates of the free water content and transmissivity values of the aquifer would facilitate cross-evaluation of the surface-water and groundwater models. MRS results indicate ranges for permeability (K = 1 × 10(-5) to 3 × 10(-4) m/s) and for free water content (w = 5% to 23% m(3) /m(3) ) narrowed by two orders of magnitude (K) and by ～50% (w), respectively, compared to the ranges of permeability and specific yield values previously considered. These shorter parameter ranges result in a reduction in the model's equifinality (whereby multiple combinations of model's parameters are able to represent the same observed piezometric levels), allowing a better constrained estimate to be derived for net aquifer recharge (～22 mm/year).  相似文献