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931.
S. P. Burlatskaya S. F. Burlatsky A. F. Burlatsky S. A. Didenko 《Izvestiya Physics of the Solid Earth》2006,42(6):510-520
It was shown in our previous works that the dipole part of the geomagnetic field direction is mainly represented by the 1200-yr variation. According to some indications, the residual of the dipole part of the field, the so-called δ variation, may be classified as standing waves. Average values of δ are calculated for each hemisphere. In this work, the difference values equal to the δ variations for each territory minus δ averages over hemispheres (western or eastern) are calculated. The resulting values, fine structure (FS) variations, characterize the FS of the geomagnetic field. The study of the activity of the FS variations and specific features of their N-S and E-W behavior and the comparative analysis of dynamic characteristics (activity and rate) give grounds to classify the FS variations (as well as the δ variations) as standing waves of the nondipole field. 相似文献
932.
V. M. Zobin E. I. Gordeev V. F. Bakhtiarov E. I. Ivanova Yu. M. Khatkevich V. N. Khodenko V. E. Levin V. P. Mityakin 《Natural Hazards》1992,6(1):51-70
The earthquake of 6 October 1987 (M = 6.6), which occurred near the Shipunsky Cape, Kamchatka, was the largest crustal event in the vicinity of the main city of Kamchatka — Petropavlovsk-Kamchatsky — during the last three decades. It was followed by numerous aftershocks. This earthquake allowed us to test the effectiveness of the seismic hazard monitoring in Kamchatka, including the seismological, geodetic and hydrogeochemical surveys. The seismic survey provided the location and source nature of the main shock and aftershocks and the seismic environment of the main shock. The geodetic and hydrogeochemical surveys have yielded data on the response to earthquakes of the Earth's surface deformations, water level, and chemical elements concentration in the underground water. As a result, the following data were obtained: The earthquake of 6 October had a seismic moment 4–10 E18 Nm, thrust type of faulting and the source volume of 20 × 20 × 10 km3. The maximum intensity was VI–VII (MSK-64 scale) and maximum acceleration 88 cm/s2. Before this event, a relative increase in the number of the upper mantle (depth more than 100 km) moderate magnitude earthquakes during 5 years and a one-year period of seismic quiescence for small shallow earthquakes, were recognized. Significant anomalies in HCO3 and H3BO3 concentrations in the underground waters were observed in the wells a week before the main shock. 相似文献
u
933.
T. A. Shatilina G. Sh. Tsitsiashvili T. V. Radchenkova 《Russian Meteorology and Hydrology》2010,35(11):740-743
Peculiarities are investigated of the air temperature variation tendencies at some stations of the Far East in 1976–2005.
The estimate of linear trend equation coefficients is computed according to the air temperature observation data using the
least squares method. It is demonstrated that the air temperature trend in northern regions possesses a small probability
at small values of residual variability. In the southern regions, the trend significance increases for almost all seasons
at small values of residual variability. At midlatitude stations, the trend significance in January and February decreases
considerably due to the large values of residual variability. 相似文献
934.
935.
Geochronology of anthropogenic pollutants in riparian wetland sediments of the Lippe River (Germany) 总被引:2,自引:0,他引:2
S. Heim J. Schwarzbauer A. Kronimus R. Littke C. Woda A. Mangini 《Organic Geochemistry》2004,35(11-12):1409
Anthropogenic pollutants were determined in a dated sediment core, collected from a riparian wetland of the Lippe River (Ruhr district, Germany). The historical trend in heavy metals, polycyclic aromatic hydrocarbons, organochlorines, polychlorinated biphenyls and linear alkylbenzenes as well as more recent contaminants such as industrial additives, organotins, synthetic musks, methyltriclosan and some other compounds were determined for the time period between 1930 and 1986. Emission sources, information on technical production and usage, as well as on the individual pollution pathways, with appropriate environmental stability, were considered in the interpretation of the sediment contamination over the past 50 years.Contaminants were analysed and interpreted according to two different criteria: (a) the origin of the main contaminants as related to mining and industrial activities as well as municipal sewage and agricultural effluents and (b) the pollution history. Due to a significant appearance of formerly missing contaminants in sediments deposited since 1970, we suggest classifying contaminants as either common (predating 1970) or modern (postdating 1970).In summary, the study provided a comprehensive reconstruction of the pollution history of the Lippe River system. 相似文献
936.
An analysis is made of the oil pollution of the Ob river waters using a long-term (1993–2013) hydrochemical monitoring of oil fields in Khanty-Mansi Autonomous Okrug. Contents of oil hydrocarbons (OHC) were determined in 4277 samples from the main Ob channel, and in 7076 samples from its anabranches by using infrared spectrometry. An increase in MAC (0.05 mg/dm3) was observed in 28% of the samples from the main channel, and in 32% from the anabranches. The total percentage of samples with an extremely high (> 50 MAC) and high (30–50 MAC) pollution level made up 0.3% of the samples for the anabranches, and 0.1% for the main channel. Maximum pollution was revealed in the eastern part of Okrug, from its eastern boundary to the mouth of the Trom’egan river which is associated with a considerable number of accidents on the pipelines within the Nizhnevartovskii district. The upper and lower quantiles in the most polluted anabranches, Pasl and Bagras, are 0.03–01.7 and 0.032–0.16 mg/dm3, respectively, whereas in the main Ob channel they vary from 0.022 to 0.065 mg/dm3 (0.4–1.2 MAC). The methods of geoinformatics and mathematical statistics were used to assess a dependence of OHC on the number of pollution sources (well clusters, and the area of oil spills) in zones at different distances from the river channels. By calculating the Spearman correlation coefficients, it was shown that OHC contents are dependent mainly on the number of wells, and on the area of oil spills located at less than 2 km from the channels. 相似文献
937.
Vasil’ev D. Yu. Vodopyanov V. V. Zayzeva G. S. Zakirzyanov Sh. I. Semenov V. A. Sivokhip Zh. T. Chibilev A. A. 《Doklady Earth Sciences》2019,486(2):724-727
Doklady Earth Sciences - The results of long-term forecasting of the spring runoff in the Belaya River basin based on the water-balance model are presented. The structure and parameters of the... 相似文献
938.
939.
A. Aparicio G. Bertelli C. Chiosi J. M. Garcia-Pelayo 《Astrophysics and Space Science》1990,169(1-2):37-39
We present preliminary results of CCD BV photometry of the old open cluster King 2. The values obtained for the main parameters are:E(B-V)=0.31, (m-M)0=13.78, metal content approximately solar, and age 6×109 yr. From the comparison with synthetic colour-mgnitude diagrams generated by models with overshoot we try to answer the question whether or not convective elements generated in the core can penetrate into the surrounding stable zone (separated by a discontinuity of molecular weight).Paper presented at the 11th European Regional Astronomical Meetings of the IAU on New Windows to the Universe, held 3–8 July, 1989, Tenerife, Canary Islands, Spain. 相似文献
940.
G. Thuillier G. Schmidtke C. Erhardt B. Nikutowski A. I. Shapiro C. Bolduc J. Lean N. Krivova P. Charbonneau G. Cessateur M. Haberreiter S. Melo V. Delouille B. Mampaey K. L. Yeo W. Schmutz 《Solar physics》2014,289(12):4433-4452
Onboard the International Space Station (ISS), two instruments are observing the solar spectral irradiance (SSI) at wavelengths from 16 to 2900 nm. Although the ISS platform orientation generally precludes pointing at the Sun more than 10?–?14 days per month, in November/December 2012 a continuous period of measurements was obtained by implementing an ISS ‘bridging’ maneuver. This enabled observations to be made of the solar spectral irradiance (SSI) during a complete solar rotation. We present these measurements, which quantify the impact of active regions on SSI, and compare them with data simultaneously gathered from other platforms, and with models of spectral irradiance variability. Our analysis demonstrates that the instruments onboard the ISS have the capability to measure SSI variations consistent with other instruments in space. A comparison among all available SSI measurements during November–December 2012 in absolute units with reconstructions using solar proxies and observed solar activity features is presented and discussed in terms of accuracy. 相似文献