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81.
Recent chemical accidents precipitated by natural disasters have prompted governments in the United States, Japan, and Europe, among other countries, to re-evaluate current practices in the design and risk management of industrial facilities. This paper presents an overview of natural hazard design considerations and external events risk management requirements in the industrial sector, with particular emphasis on industrial practices in the United States, Japan, and Europe. The analysis shows that although regulations exist to ensure industrial plant structures are built to resist natural hazards (up to the design level), there are few laws to address the performance of non-structural elements and safety and emergency response measures during a natural disaster. Laws usually also refer to natural hazards only indirectly, and provisions to prevent or respond to simultaneous disasters from single or multiple sources concurrent with the natural disaster are usually not present.
Ana Maria CruzEmail:
  相似文献   
82.
A strong earthquake (M J 6.9, M W 6.6–6.7) at about 11 km depth hit the western shore of the Noto Peninsula on Honshu, Japan, at about 00:42 coordinated universal time (9:42 a.m. local time) on 25 March 2007 (the Noto Hanto Earthquake in 2007). The earthquake triggered only 61 landslides, with most traveling short distances. It caused one long run-out landslide in the Nakanoya district of Monzen town, Wajima city, Ishikawa Prefecture, when a portion of a deep-seated landslide transformed into a moderate debris slide down a channel. The rock slide occurred on a south-facing convex-shaped slope on a small spur where earthquake ground shaking likely was strongly amplified by topography. A portion of the rock slide reached a small channel floored by materials containing abundant groundwater. Constant-volume box-shear tests on normally consolidated saturated specimens revealed that the apparent angle of internal friction of the channel-floor material was 33–36° at 10-mm shear displacement and did not show much decrease in effective normal stress during shearing. In situ rock-sliding testing on the exposed channel materials showed a low kinetic-friction angle of about 21°. We suggest that an unsaturated portion of the rock slide slid down the channel, with sliding between the rock-slide mass and the channel floor. Because the slope angle of the travel path nearly equaled the kinetic-friction angle, the unsaturated rock slide mass may have traveled at a moderately slow speed, or it might have decelerated and accelerated. Slow speed is supported by accounts from local residents that suggest movement of debris continued for 3 days after the main shock.  相似文献   
83.
Observations of deep ocean temperature and salinity in the Labrador and Greenland Seas indicate that there is negative correlation between the activities of deep convection in these two sites. A previous study suggests that this negative correlation is controlled by the North Atlantic Oscillation (NAO). In this study, we discuss this deep convection seesaw by using a coupled atmosphere and ocean general circulation model. In this simulation, the deep convection is realistically simulated in both the Labrador and Greenland Seas and their negative correlation is also recognized. Regression of sea level pressure to wintertime mixed layer depth in the Labrador Sea reveals strong correlation between the convection and the NAO as previous studies suggest, but a significant portion of their variability is not correlated. On the other hand, the convection in the Greenland Sea is not directly related to the NAO, and its variability is in phase with changes in the freshwater budget in the GIN Seas. The deep convection seesaw found in the model is controlled by freshwater transport through the Denmark Strait. When this transport is larger, more freshwater flows to the Labrador Sea and less to the Greenland Sea. This leads to lower upper-ocean surface salinity in the Labrador Sea and higher salinity in the Greenland Sea, which produces negative correlation between these two deep convective activities. The deep convection seesaw observed in the recent decades could be interpreted as induced by the changes in the freshwater transport through the Denmark Strait, whose role has not been discussed so far.  相似文献   
84.
Seasonal variations in the primary production regime in the upper water column were assessed by shipboard observations using hydrocasts and natural fluorescence profiling at a fixed station in the central part of Sagami Bay, Japan. The observations were conducted as a part of ‘Project Sagami’ dedicated to the interdisciplinary study of seasonality in bathyal benthic populations and its coupling with water column processes. Based on the time-series observations at intervals of about 1 to 2 months, primary productivity in terms of chlorophyll abundance appeared to be elevated during the spring of 1997, but the observed peaks of biomass were much less significant in the spring of 1998. Meanwhile, the organic matter flux, as indicated by sediment trap data and benthic observations, had a significant peak in the spring of 1998 as well, and its magnitude was comparable to that in 1997. Satellite images of ocean color obtained during the spring of 1997 indicate the importance of events with time scales much shorter than a month, and suggest qualitative differences in the phytoplankton community in the euphotic zone for each bloom event during this period. The possible mechanisms that could yield the spring maximum of material input to the benthic community are discussed.  相似文献   
85.
The thermal phase transformation of the iron-manganese phase of the Pacific Ocean manganese nodules were studied by the differential thermal and X-ray diffraction methods. X-ray powder patterns of the heated samples at the temperature of 600°C to 1000°C show the occurrence of hematite, bixbyite and cubic and tetragonal (Fe, Mn)3O4. Bixbyite produced by the heat treatment of the iron-manganese phase gives an abnormal X-ray pattern in comparison with the standard sample of bixbyite. Cubic (Fe, Mn)3O4 is produced not only by the reaction of bixbyite with hematite over 900°C, but also at the lower temperature, such as 600°C. While, tetragonal (Fe, Mn)3O4 is a reaction product of cubic (Fe, Mn)3O4 with bixbyite over 900°C in the case of manganese rich nodules. The species and quantities of the products after the heat treatment are assumed to be mostly influenced by the relative contents of iron and manganese in the manganese nodule.  相似文献   
86.
In order to estimate the path latitude of low-latitude whistlers, the measurement of the direction of arrival (bearing and elevation) and the polarization has been successfully carried out a low-latitude station at Takayama (geomag. lat. 26°), by using our newly developed electronic devices. Our system of using two crossed loops and a vertical monopole is, in principle, based on Crary's method and is effective for elliptically polarized waves. The measurements were made at a specific frequency of 4.5 kHz.The main results of our preliminary experiments are (i) the exit points of observed whistlers are located several tens of kilometers approximately north-north-east of the observing site and (ii) although a few whistlers have shown the polarization very close to circular, the polarization of most whistlers are generally elliptical, indicating the effect of multi-rays propagating in the Earth- ionosphere waveguide.  相似文献   
87.
The Jiayin area along the Heilongjiang River in Northeast China has attracted stratigraphic and sediment-ological interests recently because the Cretaceous-Tertiary (K/T) boundary should be located in this non-marine succession. Dinosaur remains disappear suddenly at the upper part of the Maastrichtian, whereas plants gradually evolved throughout the succession. Analysis of sedimentary facies has been carried out and paleo-environments through Upper Cretaceous to lower Paleocene sections are reconstructed. Fluvial to lacustrine sedimentary environments are inferred from the facies. Several debris flow events have been identified, and it is in these deposits that the dinosaur fossils are concentrated.  相似文献   
88.
It is well known that a counterclockwise rotation occurred in the Miocene in northeast Japan. However, the detailed timing and mechanism of the rotation has been debated. Moreover, there has been no research about the relationship between rotational tectonics and the evolution of sedimentary basins. We carried out paleomagnetic and rock magnetic analyses in Nishiwaga Town, Iwate Prefecture, northeast Japan, where the stratigraphy and sedimentary basin formation have previously been clarified. We found that there was a counterclockwise rotational movement of about 45° at about 15 Ma. From our results and previous studies on the tectonics and sedimentary basin development, we are able to ascertain the following tectonic history and sedimentary basin evolution in this area: (i) before the rotational movement, sandstone and mudstone were deposited in a tranquil environment with no volcanic activity coupled with slow tectonic subsidence; (ii) between 16.4–15.1 Ma and 14 Ma, a counterclockwise rotation occurred with rapid tectonic subsidence and continuous explosive volcanism; (iii) at about 14 Ma, the counterclockwise rotation ended and there was a reduction in both subsidence and volcanism. This result shows the impact that rotational tectonics can have on sedimentary basin formation.  相似文献   
89.
Source model of Noto-Hanto-Oki earthquake tsunami of 7 February 1993   总被引:1,自引:0,他引:1  
A source model was discussed for a small tsunami accompanied by the Noto-Hanto-Oki earthquake (M s 6.6), striking Japan on 7 February, 1994. Assuming a fault model under the sea bottom, we estimated the focal parameters jointly, using synthesized tsunami source spectra as well as the tsunami numerical simulation. The fault proposed by this study consists of a plane sized 15×15 km, dipping N47°W with the dip angle of 42°, which is almost pure reverse fault (slip angle 87°) with a dislocation of 1 meter. The numerical simulation shows that the shallow sea in the source region caused a comparatively long recurring tsunami (the periods are 12–18 minutes) in spite of its small size. The model fault is corresponding to an aftershock area of this earthquake.  相似文献   
90.
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