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91.
Ucan Osman N. Albora A. Muhittin Hisarli Z. Mümtaz 《Marine Geophysical Researches》2001,22(4):251-264
In this paper, residual and regional gravity and magnetic anomalies of Saros Bay are separated using wavelet method. Wavelet
is one of the modern, stochastic image approaches processing technique in electronics. The vertical, horizontal and diagonal
components of wavelet output are evaluated simultaneously and an underground model is obtained by suitable cross-sections.
Thus the geological and tectonic properties of Saros Bay are extracted. Our proposed model is confirmed by deep and shallow
seismic researches of Turkish Petroleum Cooperation (TPAO). The South-East region of Saros Graben is formed by strike slip
Ganos Fault and Anafartalar reverse Fault that lies on the east of Ganos Fault. On the Northwest region, there is strike slip
component fault resulting in the Enez Graben. Here we detected two new oval type geological structure, both of them starting
from the Eastern direction of Canakkale Dardanelles and but one of them continuing through Gelibolu Peninsuls, while the other
tending to the Enez Graben. We think that these structures are the ruins of a very old sea in this region.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
92.
The paper is intended to extend the investigations about the nature of abnormal waves that have been reported in the work of Guedes Soares et al. (Characteristics of abnormal waves in North Sea states. Applied Ocean Research 25, [337–344]). The same dataset gathered at the oil platform North Alwyn in the North Sea during the November storm in 1997 is used along with the time series from the Draupner platform, in which an abnormal wave occurred. The data are reanalyzed from the viewpoint of the applicability of second-order models to fit large waves. The observed results confirm that the second-order approximation is not adequate to describe highly asymmetric and abnormal waves. 相似文献
93.
94.
Wave-induced seabed instability, either momentary liquefaction or shear failure, is an important topic in ocean and coastal engineering. Many factors, such as seabed properties and wave parameters, affect the seabed instability. A non-dimensional parameter is proposed in this paper to evaluate the occurrence of momentary liquefaction. This parameter includes the properties of the soil and the wave. The determination of the wave-induced liquefaction depth is also suggested based on this non-dimensional parameter. As an example, a two-dimensional seabed with finite thickness is numerically treated with the EFGM meshless method developed early for wave-induced seabed responses. Parametric study is carried out to investigate the effect of wavelength, compressibility of pore fluid, permeability and stiffness of porous media, and variable stiffness with depth on the seabed response with three criteria for liquefaction. It is found that this non-dimensional parameter is a good index for identifying the momentary liquefaction qualitatively, and the criterion of liquefaction with seepage force can be used to predict the deepest liquefaction depth. 相似文献
95.
96.
This study takes cognizance of the fact that the TIOMIN (TIOMIN Resources Inc. of Canada) project has resulted in controversy over its handling of environmental issues and especially the Environmental Impact Assessment (EIA). The authors address many of the protracted issues that have slowed the development of the mining project in Kwale. The main emphasis is on the impacts of the mining and mineral separation processes on the environment, including the governing legislation, the role of consultation and public participation, and socioeconomic issues. In their public documents TIOMIN has specified neither the type of minerals it wants to extract from the area nor their chemical composition. It is well known, however that the titanium minerals and zircon targeted have impurities of iron, thorium and uranium. In the absence of an Environmental Management Plan, the effects of stockpiling radioactive wastes and other impurities that could possibly lead to environmental degradation in both the terrestrial and marine environments have not been publically addressed. The measures proposed to mitigate ecological damage as a result of the establishment of a minerals processing plant in the area seem inadequate. Pollution resulting from accidental spillage or breakage could have significant impact on marine life and residents living near the mining site. Other issues that have not been addressed satisfactorily pertain to the use of surface and underground water. The area already faces a huge water deficit and the calculations presented on aquifer recharge and stream flow rates do not indicate the large quantities of water that would be required in the mineral processing plant. The project, if approved in its present state, risks violation of international conventions. Furthermore, it could cause a conflict between Kenya and Tanzania in the event of an oil spill at the proposed ship loading facility at Shimoni. The proposed mining area includes the district's most fertile land, is home to many fisherfolk and is a major tourist destination. An analysis of the effects of this project on other available opportunities must be thoroughly understood to ascertain the economic and environmental benefits and costs of the mining venture. The proposed compensation rate of $1,000 per acre, for resettlement for example, appears to be grossly inadequate. Compensation should take into account family size and structure family assets and the cost of relocation. 相似文献
97.
以细角滨对虾Litopenaeus stylirostris为实验对象,按时间顺序观察了胚胎各期的形态特征。通过解剖从无节幼体到仔虾第1天各期幼体的附肢,对其发育形态及其刚毛着生方式进行了描述和统计。比较研究了细角滨对虾和凡纳滨对虾L.vannamei无节幼体期形态差异以及色素的变化、溞状幼体期眼上棘形态的差异以及大颚齿数目。结果表明,无节幼体期细角滨对虾的色素明显多于凡纳滨对虾;两者溞状幼体期眼上棘的形态存在明显差异;两者在无节幼体至仔虾第1天各期大颚活动齿的数目变化一致。 相似文献
98.
Background signal of the scintillation detector routinely used for atmospheric Kr-85 counting follows fluctuations, and their connection with cosmic ray variations is searched for. A strong correlation between the 27-day moving average of sunspot numbers and the background is obtained from the 1988 data. 相似文献
99.
Atίla Özgüç 《Solar physics》1989,123(2):381-383
After re-examination of data presented by Verma (1984), some misuse of solar parameteres published in Solar Geophysical Data is presented. Consequently some conclusions made by Verma (1984, 1986) on about the longitudinal distribution of cool solar surges based on these misuses are discussed. 相似文献
100.
Taking into account the effect of roughness (or local departures from sphericity) of the emitting layers in the chromosphere-corona transition zone (CCT) allows one to determine the optical depths of layers responsible for resolved structures in Cii, Ciii, Oiv, and Ovi lines. The result, at the top of the irregularities, is of the order of respectively 1 3.5,2.0, 1.6,0.5, and for the bottom of these irregularities, 2 = 0.7, 0.4, 0.3, 0.25. The characteristic angle of these irregularities is, respectively, of the order of 35 °, 33 °, 35 °, and 41 °. For unresolved structures of Civ and Ovi (already analyzed in the spherical symmetry hypothesis in Paper III), one finds 1 0.6; 0.9 and 2 0.12; 0.2 in the case of quiet areas; in the case of active areas, the range is broader for Civ and Ovi, from 1.0 to 1.7 for 1 and from 0.2 to 0.9 for 2. The values obtained from Ovi are in reasonable agreement with each other for resolved and unresolved structures. And the obtained values of 1 and 2 correspond not too badly with the determinations made in Paper III, by methods not exceedingly influenced by the spherical symmetry hypothesis. 相似文献