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Vadim Vasilevich Novotryasov Dmitry Vadimovich Stepanov Igor Olegovich Yaroshchuk 《Ocean Dynamics》2016,66(1):19-25
Observations are presented of internal undular bores (IUBs) on the Japan/East Sea coast. We found three types of IUB amplitude modulation functions. The first type (IUB1) has a leading edge, which is formed by the soliton with maximal amplitude. The second type (IUB2) has a soliton with maximal amplitude (SMA) located between the leading and trailing edges. The third type (IUB3) consists of 2–3 solitons, which have identical amplitudes. The evolution of the IUB2 from the moment of generation to the moment of maximal development was analyzed. The speed of the IUB2 approached to the phase speed of linear internal waves with a period of 12.4 h. The amplitude modulation function of the IUB2 is believed to be unique in ocean observations. Observations are discussed in the context of recently raised hypotheses concerning the evolution of IUBs in the coastal environment. 相似文献
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徐经纬 徐敏 蒋熹 ArmelleReca C. Remedio Dmitry V. Sein Nikolay Koldunov Daniela Jac 《气候变化研究进展》2016,12(4):286-293
采用泰勒图和偏差分析等统计方法,评估分析了德国区域气候模式(REMO)对中国1989-2008年气温和降水的模拟能力。结果表明:REMO气温模拟值与观测值空间相关系数为0.94,降水空间相关系数较低(0.42),气温模拟结果明显优于降水;从空间偏差上看,在中国大部分地区,REMO模拟的气温高于观测值,偏差在±4℃以内,青藏高原整体有明显的-4~-2℃的冷偏差;模拟的降水值则高于观测值,空间偏差分布较均匀,中国大部分地区偏差在±300 mm之内;除青藏高原、华南和西南地区外,REMO能较准确地反映出中国气温和降水的空间分布特征,其中华北和东北地区模拟效果最好;REMO对夏季气温和冬季降水的模拟能力相对较好;REMO在地形起伏较大地区的模拟能力有待提高。 相似文献
125.
Michael T.D. Wingate Sergei A. Pisarevsky Dmitry P. Gladkochub Tatiana V. Donskaya Konstantine M. Konstantinov Anatoly M. Mazukabzov Arkady M. Stanevich 《Precambrian Research》2009,170(3-4):256-266
We present a new, reliably dated Mesoproterozoic paleopole for Siberia, based on a combined geochronological and paleomagnetic study of mafic rocks within the Mesoproterozoic Sololi Group of the Olenek Uplift in northern Siberia. Ion microprobe (SHRIMP) U–Pb analysis yields crystallisation ages of 2036 ± 11 Ma for zircon from a basement granite and 1473 ± 24 Ma for baddeleyite from a large dolerite sill within the Kyutingde Formation. The baddeleyite result indicates that the lower Sololi Group is significantly older than was suggested by previous K–Ar results. Paleomagnetic analysis of the dolerite sill and related mafic intrusive rocks yields a paleopole at 33.6°N, 253.1°E, A95 = 10.4°. A positive baked-contact test between the Kyutingde sill and sedimentary country rocks shows that the magnetisation is primary. Comparison of this paleopole with coeval results for Laurentia provides a revised reconstruction between Siberia and Laurentia, and implies that these two continents were parts of a single Mesoproterozoic supercontinent since at least 1473 Ma. We argue that Siberia, Laurentia, and Baltica belonged to the same supercontinent between 1473 Ma and mid-Neoproterozoic time. 相似文献
126.
Vladimir Traskine Zoya Skvortsova Alexey Muralev Dmitry Zubov 《Mineralogy and Petrology》2009,97(3-4):265-274
Pressure solution creep was studied on sodium chloride, calcium carbonate and ammonium nitrate in respective saturated aqueous solutions under static loading and cyclic unloading. Ball indentation and powder compaction curves show that each transition from static to cyclic regime produces an increase—sometimes manifold—in creep rate which lasts over the whole time of cyclic impact. After returning to static regime, the initial creep rate reappears. Over longer-term tests, both in static and cyclic regime, the creep gradually slows down. Increasing impact frequency enhances the effect. Any noticeable changes in strain rate are absent in a pure inert medium (paraffin oil). Possible mechanisms of the cyclic unloading effect are discussed. 相似文献
127.
Victor A. Melezhik Anthony E. Fallick Michail M. Filippov Aivo Lepland Dmitry V. Rychanchik Yuliya E. Deines Pavel V. Medvedev Alexander E. Romashkin Harald Strauss 《地学学报》2009,21(2):119-126
Early Palaeoproterozoic rocks from the Onega Basin in Russian Fennoscandia contain evidence for substantial accumulation and preservation of organic matter (up to 75 wt% total organic carbon) with an estimated original petroleum potential comparable to a modern supergiant oilfield. The basin contains a uniquely preserved petrified oilfield including evidence of oil traps and oil migration pathways. Here, we report the discovery of the surface expression of a migration pathway, along which petroleum was flowing from the sub-surface. This surface oil seep, the first occurrence ever reported from the Palaeoproterozoic, appears as original bitumen clasts redeposited in Palaeoproterozoic lacustrine turbidites. The δ13 Corg of clastic pyrobitumen ranges between −35.4 and −36.0‰ ( n = 14), which is within the range of interbed- and vein-trapped fossil oil (−46 and −24‰), suggesting similar source. Biogenic organic matter, whose isotopic composition was modified during thermal maturation, is the likely source for the migrated hydrocarbon. 相似文献
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129.
Dmitry Tatarnikov Vladimir Filippov Igor Soutiaguine Andrey Astahov Anton Stepanenko Pavel Shamatulsky 《GPS Solutions》2005,9(3):194-201
An antenna ground plane (GP) plays a major role in the mitigation of multipath coming from underneath the antenna. A distinct
trend in user antenna size and weight reduction has been observed during recent years. With this focus in mind, an overview
of conventional flat conductive and impedance GP is provided. Results of modern developments of passive vertically stacked
structures are discussed. The possibility of obtaining a reasonable level of multipath mitigation with vertical structures
of several centimeters is shown. 相似文献
130.
A method for multiscale parameter estimation with application to reservoir history matching is presented. Starting from a
given fine-scale model, coarser models are generated using a global upscaling technique where the coarse models are tuned
to match the solution of the fine model. Conditioning to dynamic data is done by history-matching the coarse model. Using
consistently the same resolution both for the forward and inverse problems, this model is successively refined using a combination
of downscaling and history matching until model-matching dynamic data are obtained at the finest scale. Large-scale corrections
are obtained using fast models, which, combined with a downscaling procedure, provide a better initial model for the final
adjustment on the fine scale. The result is thus a series of models with different resolution, all matching history as good
as possible with this grid. Numerical examples show that this method may significantly reduce the computational effort and/or
improve the quality of the solution when achieving a fine-scale match as compared to history-matching directly on the fine
scale. 相似文献