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981.
F. Sacchetti S. Benetti A. Georgiopoulou P.M. Shannon B.M. O'Reilly P. Dunlop R. Quinn C. Ó Cofaigh 《Marine Geology》2012
The continental margin offshore of western Ireland offers an opportunity to study the effects of glacial forcing on the morphology and sediment architecture of a mid-latitude margin. High resolution multibeam bathymetry and backscatter data, combined with shallow seismic and TOBI deep-towed side-scan sonar profiles, provide the basis for this study and allow a detailed geomorphological interpretation of the northwest Irish continental margin. Several features, including submarine mass failures, canyon systems and escarpments, are identified in the Rockall Trough for the first time. A new physiographic classification of the Irish margin is proposed and linked to the impact of glaciations along the margin. Correlation of the position and dimensions of moraines on the continental shelf with the level of canyon evolution suggests that the sediment and meltwater delivered by the British–Irish Ice Sheet played a fundamental role in shaping the margin including the upslope development of some of the canyon systems. The glacial influence is also suggested by the variable extent and backscatter signal of sedimentary lobes associated with the canyons. These lobes provide an indirect measurement of the amount of glaciogenic sediment delivered by the ice sheet into the Rockall Trough during the last glacial maximum. None of the sedimentary lobes demonstrates notable relief, indicating that the amount of glaciogenic sediment delivered by the British–Irish Ice Sheet into the Rockall Trough was limited. Their southward disappearance suggests a more restricted BIIS, which did not reach the shelf edge south of 54°23′ N. The various slope styles observed on the Irish margin represent snapshots of the progressive stages of slope development for a glacially-influenced passive margin and may provide a predictive model for the evolution of other such margins. 相似文献
982.
983.
S. P. Zakharkov V. B. Lobanov T. N. Gordeichuk T. V. Morozova E. A. Shtraikhert 《Oceanology》2012,52(3):354-363
To evaluate the structure and photosynthetic activity of the phytoplankton of the northwestern part of the Sea of Japan, the results of the surveys conducted from February 26 to March 9, 2003, during the 30th cruise of the R/V Akademik Lavrentyev were used. The species composition was considered taking into account the influences of the hydrological conditions. In particular, the studied water area was divided into four zones with various sizes of the mixed layer depth (MLD). An inverse relationship between the MLD and the content of chlorophyll a (Chl a) in various zones was established. The diatom algae were the basic dominants of the composite structure of the phytoplankton everywhere. It is revealed that, at a MLD increase, smaller forms of microalgae receive development. The intrapopulation relations are caused by the adaptation of various species of phytoplankton to the influence of external factors, among which the size of MLD is fundamental. 相似文献
984.
A.M. Lundmark R.H. Gabrielsen H. Austrheim K. Flaat T. Strand S.E. Ohm 《Marine and Petroleum Geology》2012,29(1):204-218
In the Embla oil field on the northern flank of the Mid North Sea High, the central North Sea, multiple quartz porphyric volcanic beds at ca. 4600 m depth form part of a volcano-sedimentary interval above the Caledonian basement as interpreted from seismic data. Zircon U–Pb laser ablation ICPMS date one bed to 374 ± 3 Ma, indicating that the volcanic rocks and interbedded sediments are early Famennian and correlate to the Buchan Formation. The volcanic rocks have been extensively clay and carbonate altered in a near-surface environment, but high field strength element data show that the protoliths were alkali rhyolites, yielding intra-plate signatures in tectonic discrimination diagrams. Famennian quartz porphyric volcanic rocks have also been reported from well A17-1 on the southern flank of the Mid North Sea High. The Famennian volcanism on the northern and southern flanks testify to an active magmatic environment in the central North Sea in the early Famennian, supporting the existence of a late Devonian proto-Central Graben rift extending northwards into the central North Sea. The rift is likely an early example of strain localisation to a zone of reduced crustal strength along the Caledonian suture between Avalonia and Baltica. 相似文献
985.
A. N. Rublev I. A. Gorchakova T. A. Udalova 《Izvestiya Atmospheric and Oceanic Physics》2011,47(2):190-200
Based on mathematical simulation, quantitative estimates of the effect that coarse dust particles have on the accuracy of retrieving the optical characteristics of aerosol have been obtained from the results of ground-based measurements of the spectral fluxes of both direct and scattered solar radiations. The results of verifying a retrieval algorithm (used at the AERONET ground-based network) based on special test models showed that the aerosol characteristics retrieved with this algorithm are unsuitable for calculating integral solar fluxes and for simulating space spectrometric IR measurements when the concentration of dust particles in the atmosphere exceeds their concentration in the well-known CONT model of continental aerosol by a factor of two or more. 相似文献
986.
S.?A.?Sitnov "mailto:ssitnov@mail.ru " title= "ssitnov@mail.ru " itemprop= "email " data-track= "click " data-track-action= "Email author " data-track-label= " ">Email author 《Izvestiya Atmospheric and Oceanic Physics》2011,47(2):166-185
The tropospheric NO2 content over the Moscow region is analyzed on the basis of data of the satellite Ozone Monitoring Instrument (OMI) in the period 2004–2009. The spatial distributions of NO2 are presented, and some of their features are interpreted. The characteristics of the seasonal and weekly cycles of NO2 are described, as are its interannual and long-term variations. The relationship between the variabilities of the NO2 content and the aerological parameters is investigated on different time scales. The mutual influence of regional pollution and meteorological regimes is discussed. The seasonal and weekly NO2 cycles over Moscow are compared with those over the largest worldwide agglomerations. 相似文献
987.
2008年,浙江省舟山市这个千岛城市将成为半岛城市,其海岛经济也将向半岛型经济转变.实现这个经济转型,首先全市上下应提高思想认识,其次三大产业的发展上要有新调整,在主攻海洋经济时,应将长三角和全国作为发展的腹地,凸现半岛在经济发展中的优势,还应处理诸如发展经济与保护资源环境等方面的关系. 相似文献
988.
Zhu Liyan ;Huang Ying ;Liu Guangxing 《海洋湖沼学报（英文）》2005,23(3):340-348
DNA damage of aquatic organisms living in polluted environments can be used as a biomarker of the genotoxicity of toxic agents to organisms. This technique has been playing an important role in ecotoxicological study and environmental risk assessment. In this article, main types of DNA damage caused by pollutants in water environments were reviewed; methods of detecting DNA damage were also documented for water environmental monitoring. 相似文献
989.
Ivanov V. A. Kubryakov A. I. Lyubartseva S. P. Mikhailova É. N. Shapiro N. B. 《Physical Oceanography》2004,14(2):67-83
In the present work, we generalize the results of our investigations in the field of simulation of hydrophysical and ecological processes in coastal regions of various seas and some closed basins. The developed and applied mathematical models and the results of numerical experiments are briefly analyzed. 相似文献
990.
The motion and the drift force of a floating OWC (oscillating water column) wave energy device in regular waves are studied taking account of the oscillating surface-pressure due to the pressure drop across the duct of the air chamber. The potential problem inside the chamber is formulated by making use of the Green integral equation associated with the Rankine-type Green function while the outer problem with the Kelvin-type Green function. The added mass, wave damping and excitation coefficients as well as the motion and drift force of the OWC device are calculated for various values of parameter related to the pressure drop. 相似文献