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991.
Pirogova A. S. Tikhotskii S. A. Tokarev M. Yu. Suchkova A. V. 《Izvestiya Atmospheric and Oceanic Physics》2019,55(11):1755-1765
Izvestiya, Atmospheric and Oceanic Physics - This paper provides an overview of several seismic inversion approaches and their application to very- and ultra-high-resolution marine seismic... 相似文献
992.
993.
Eighty-nine juvenile Atlantic sturgeon,Acipenser oxyrhynchus oxyrhynchus, including 10 recaptures, were collected, tagged and released in the upper tidal Delaware River between July 1981 and December 1984. All were captured in the river channel between Roebling and Trenton, New Jersey, using bottom-set experimental gill nets during daylight hours. The species was present from July through December and collected in increased numbers in the past two years. The fork lengths ranged from 284 to 862 mm (mean±SD = 516 mm±106 mm) and the weights from 140 to 4,250 g (mean±SD = 1,369 g±815 g). Ten juvenile Atlantic sturgeon were recaptured between September 1983 and December 1984 and were at large from one to 418 d. Recapture data suggest that these sturgeon utilize this area annually from July through December, possibly as a nursery. Juvenile Atlantic sturgeon appear to utilize the upper tidal portion of the Delaware River for a much longer period of time and at lower temperatures than in other river systems. 相似文献
994.
Jasem M. Karam 《GeoJournal》1993,31(4):383-392
The study of electoral geography in Kuwait has proven to be an interesting field for its reflection of a regional and national democratic approach in governing the state. The first consultative council was established in 1920, to be followed by the first legislative council in 1938 formed by means of elections. These two councils gave way to the first formation of a state parliament in 1963. Its history was faltered a number of times firstly in 1976 and secondly in 1986.Following the liberation, Kuwait restored its parliamentary life and elections took place on October, 5th 1992. Elections results were different to those of the previous ones where tribalism and sectarianism (Sunnis vis-a-vis Shiites) had little effect on the final results of the votes. Nevertheless, religious fundamentalist movements succeeded in winning more seats than in the past.Kuwaitis in general have become convinced that democracy is the right path for ruling the country, therefore Kuwaitis are very eager to see the success of their parliamentary experience not just for them but for the sake of the entire Gulf region. 相似文献
995.
Oceanic crust west of North America at the beginning of the Jurassic belonged to the Kula plate. The development of the western margin of North America since the Jurassic reflects interaction with the Kula plate, the Kula-Farallon spreading center and the Farallon plate. The Kula plate ceased to exist in the Paleocene and later developments were caused by interaction of the Farallon plate and, subsequently, collision with the East Pacific Rise.At the beginning of the Jurassic, when spreading between North and South America began, the Kula-Farallon-Pacific triple junction moved to the north relative to North America, and the eastern end of the Kula-Farallon spreading center swept northwards along the continental margin.During the Paleocene, Kula-Pacific spreading ceased and the Kula plate fused to the Pacific plate. Throughout the Mesozoic, subduction of the Kula plate took place along the Alaskan continental margin. When the Kula plate joined the Pacific plate a new subduction zone formed along the line of the present Aleutian chain.Wrangellia and Stikinia, anomalous terrains in Alaska and northwestern Canada respectively, were emplaced by transport on the Kula plate from lower latitudes. Hypotheses which require transport of these plates in the Mesozoic from the “far reaches of the Pacific” ignore the problem of transport across either the Kula-Pacific or Kula-Farallon spreading centers. The interaction of the Kula plate and western North America throughout the Jurassic and the Cretaceous should result in emplacement of these terrains by motion oblique to the continental margin. Tethyan faunas in Stikinia must come from the western end of Tethys between North and South America, not the Indonesian region at the eastern end of Tethys.As the northeastern end of the Kula-Farallon ridge moved northward, the sense of motion changed from right lateral shear between the Kula and North American plates to collision or left lateral shear between the Farallon and North American plates. Left lateral shear along zones analogous to the Mojave-Sonora megashear may have been the means by which anomalous terrains were transported to the southeast into the gap between North and South America forming present day Central America. Such a model overcomes the overlap difficulties suffered in previous attempts to reconstruct the Mesozoic paleogeography of Central America. 相似文献
996.
It is shown that the annealing kinetics of fission tracks in apatite can be described by a sum of exponential decay functions. From an analysis of the temperature dependence of this annealing law it is concluded that the etchability of fission tracks is due to extended defects, i.e. systems of dislocation loops. The multiexponential annealing law is also applied to prove that the plateau correction method is basically correct, but rather as a method for determining a lower limit than the “true” fission track age. 相似文献
997.
998.
Astronomy Reports - A large fraction of the energy released during the gravitational collapse of the core of a massive star is carried by neutrinos. Neutrinos play the main role in explaining... 相似文献
999.
R. R. Gabdullin N. V. Badulina E. A. Bakai E. V. Rubtsova A. Yu. Yurchenko E. V. Karpova A. V. Ivanov M. A. Varzanova A. V. Sergienko T. A. Konovalova M. V. Parakhina 《Moscow University Geology Bulletin》2018,73(4):346-360
The composition and origin of the Callovian–Oxfordian deposits of the Sudak Bay were characterized on the basis of the generalization and analysis of our own results, as well as published and unpublished data. The botanical future was first implemented for the geological mapping of the Oxfordian deposits. 相似文献
1000.
V. I. Grebenshchikova M. I. Kuzmin O. A. Proydakova O. V. Zarubina 《Doklady Earth Sciences》2018,480(2):735-740
The long-term data (1950–2017) on the chemical composition of the water from the source of the Angara River, which is the only run-off from Lake Baikal, a large and clean fresh water reservoir, are presented. The absence of water contamination despite the anthropogenic influence is shown. The similarity and constancy of the current composition of the waters in the lake and the Angara River are recorded. It is recommended to continue geochemical studies of this unique world heritage site. 相似文献