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801.
802.
Multicomponent observation of crustal activity in the DPRI 800 m borehole close to the Nojima Fault 总被引:1,自引:0,他引:1
Hiroshi Ishii Atsushi Mukai Kunio Fujimori Shigeru Nakao Shigeo Matsumoto Yasuhiro Hirata 《Island Arc》2001,10(3-4):282-287
Abstract An 800 m borehole was drilled near the Nojima Fault, on which a strike–slip larger then 1 m occurred during the 1995 Hyogo-ken Nanbu earthquake ( M = 7.2). Crustal activity near the fault has been observed since May 1996 using a multicomponent instrument installed at the bottom of the borehole. Data of three components of strain, two components of tilt and temperature observed from May 1996 to December 1998 were analyzed. Long-term changes of strain and tilt show a north-east–south-west extension and southwards subsidence. As for the Earth tides and atmospheric effect, orientation of the principal axis of strain was mainly east-west and orientation of the maximum subsidence was mainly north-south. The observational data of strain had variations corresponding to a change in temperature at a depth of 800 m. The thermal expansion coefficient of the crust was calculated to be approximately 2.0 × 10−6 /°K. 相似文献
803.
INTRODUCTIONNumeroustinybacteriaareextensivelydistributedinthesea .Theydecomposeabundantorganizmandplanktondetritus ,transformingthemintoinorganicmaterialsintheseawater .Thebacteriautilizeddissolvableorganiccarbon (DOC) ;theprotozoanatethebacteria .AndtheD… 相似文献
804.
Characterizing heterogeneous soil water flow and solute transport using information measures 总被引:1,自引:0,他引:1
Heterogeneous water flow and solute transport in soils are an important phenomenon and difficult to be characterized. The objectives of this study were to investigate the heterogeneity of solute transport related to heterogeneous soil water flow using dye infiltration experiments, and to characterize heterogeneous water flow and solute transport in soils using the information theory. Field experiments of dye infiltration were performed in four plots. Various information measures were applied to characterize information content and complexity of water flow and solute transport in soils. Information contents and complexities of the maximum and apparent infiltration depths, and the mean and standard deviation of concentrations in the vertical direction of the plots were calculated. More heterogeneous processes of soil water flow and transport result in higher information/complexity values. The probability distributions of mean concentration were similar to those of the corresponding apparent infiltration depths for the plots, indicating that heterogeneity of dye concentrations was closely related to that of soil water flow. However, the range of information entropy and complexity of the water flow sequences was much narrower than that of the sequences of the concentrations. The results suggested that the transport processes were more heterogeneous than the water flow processes. Compared with the probability distributions of flow parameters, the information measures appeared to be a more versatile tool to describe flow and transport heterogeneities in soils. 相似文献
805.
Yuji Sano Hiroshi Wakita Stanley N. Williams 《Journal of Volcanology and Geothermal Research》1990,42(1-2)
We have collected 14 water and gas samples from 9 thermal springs and gas vents near Nevado del Ruiz volcano, Colombia. The 3He/4He and 4He/20Ne ratios vary significantly from 0.98 Ratm (where Ratm is the atmospheric 3He/4He ratio of 1.4 × 10−6) to 6.30 Ratm, and from 0.37 to 7.0, respectively. The 3He/4He ratio (corrected for air contamination) decreases with increasing distance from the central crater of the volcano to the sampling site. The trend is very similar to that observed at Ontake volcano, Japan. A hydrodynamic porous-media dispersion model can explain the 3He/4He trend. The temporal variations in the 3He/4He ratio at four sites provide useful information on the apparent velocity of the magmatic fluid flow brought on by a volcanic eruption. The estimated value of several tens m day−1 agrees well with the inferred velocity of flow in Oshima volcano, Japan and is comparable to the largest rate of groundwater movement in a deep sedimentary basin. 相似文献
806.
Huang Jinbai Wen Jiawei Hinokidani Osamu Yasuda Hiroshi 《Environmental Earth Sciences》2014,72(9):3623-3633
The objectives of this study were to examine the runoff characteristics and to estimate water budget at the wind–water erosion crisscross region on the Loess Plateau of China. A small catchment known as Liudaogou that has representative meteorological and hydrological conditions of the wind–water erosion crisscross region was chosen as the study location. A numerical model for rainfall-runoff was developed and verified; rainfall-runoff calculation for 5 years (2005–2009) was performed. The observed data and numerical result of the surface runoff were used for evaluating runoff characteristics and estimating the annual water budget. Runoff rate was proportional to average intensity of rain. Even though rainfall duration was for few minutes, surface runoff was generated by intensity of more than 2.6 mm × 5 min?1, when rainfall duration exceeded 10 h; surface runoff was generated by an intensity of 0.6 mm × 5 min?1, while annual runoff rate was 10–15 %. The unit area of 1 km2 was adopted as the index area for estimating annual water budget. Runoff, evapotranspiration, variation of water storage, and habitant water consumption accounted for 20.4, 75.6, 0, and 4 % of the total annual precipitation, respectively. Results of this study provide the basis for further research on hydrology, water resources, and sustainable water development and utilization at the wind–water erosion crisscross region on the northern Loess Plateau where annual water resources are relatively deficient. 相似文献
807.
Alignmentsilkwormsasseismicanimalanomalousbehavior(SAAB)andelectromagneticmodelofafault:atheoryandlaboratoryexperimentMOTO... 相似文献
808.
Apip Kaoru Takara Yosuke Yamashiki Kyoji Sassa Agung Bagiawan Ibrahim Hiroshi Fukuoka 《Landslides》2010,7(3):237-258
This paper describes the potential applicability of a hydrological–geotechnical modeling system using satellite-based rainfall
estimates for a shallow landslide prediction system. The physically based distributed model has been developed by integrating
a grid-based distributed kinematic wave rainfall-runoff model with an infinite slope stability approach. The model was forced
by the satellite-based near real-time half-hourly CMORPH global rainfall product prepared by NOAA-CPC. The method combines
the following two model outputs necessary for identifying where and when shallow landslides may potentially occur in the catchment:
(1) the time-invariant spatial distribution of areas susceptible to slope instability map, for which the river catchment is
divided into stability classes according to the critical relative soil saturation; this output is designed to portray the
effect of quasi-static land surface variables and soil strength properties on slope instability and (2) a produced map linked
with spatiotemporally varying hydrologic properties to provide a time-varying estimate of susceptibility to slope movement
in response to rainfall. The proposed hydrological model predicts the dynamic of soil saturation in each grid element. The
stored water in each grid element is then used for updating the relative soil saturation and analyzing the slope stability.
A grid of slope is defined to be unstable when the relative soil saturation becomes higher than the critical level and is
the basis for issuing a shallow landslide warning. The method was applied to past landslides in the upper Citarum River catchment
(2,310 km2), Indonesia; the resulting time-invariant landslide susceptibility map shows good agreement with the spatial patterns of
documented historical landslides (1985–2008). Application of the model to two recent shallow landslides shows that the model
can successfully predict the effect of rainfall movement and intensity on the spatiotemporal dynamic of hydrological variables
that trigger shallow landslides. Several hours before the landslides, the model predicted unstable conditions in some grids
over and near the grids at which the actual shallow landslides occurred. Overall, the results demonstrate the potential applicability
of the modeling system for shallow landslide disaster predictions and warnings. 相似文献
809.
Ozone depression in the polar stratosphere during the energetic solar proton event on 4 August 1972 was observed by the backscattered ultraviolet (BUV) experiment on the Nimbus 4 satellite. Distinct asymmetries in the columnar ozone content, the amount of ozone depressions and their temporal variations above 4 mb level (38 km) were observed between the two hemispheres. The ozone destroying solar particles precipitate rather symmetrically into the two polar atmospheres due to the geomagnetic dipole field These asymmetries can be therefore ascribed to the differences mainly in dynamics and partly in the solar illumination and the vertical temperature structure between the summer and the winter polar atmospheres. The polar stratosphere is less disturbed and warmer in the summer hemisphere than the winter hemisphere since the propagation of planetary wave from the troposphere is inhibited by the wind system in the upper troposphere, and the air is heated by the prolonged solar insolation. Correspondingly, the temporal variations of stratospheric ozone depletion and its recovery appear to be smooth functions of time in the (northern) summer hemisphere and the undisturbed ozone amount is slighily, less than that of its counterpart. On the other hand, the tempotal variation of the upper stratospheric ozone in the winter polar atmosphere (southern hemisphere) indicates large amplitudes and irregularities due to the disturbances produced by upward propagating waves which prevail in the polar winter atmosphere. These characteristic differences between the two polar atmospheres are also evident in the vertical distributions of temperature and wind observed by balloons and rocker soundings. 相似文献
810.
The distribution and dynamics of water molecules and monovalent cations (Li+, Na+, K+, Cs+, and H3O+) on muscovite surfaces were investigated by molecular dynamics (MD) simulations. The direct comparison of calculated X-ray reflectivity profiles and electron density profiles with experiments revealed the precise structure at the aqueous monovalent electrolyte solutions/muscovite interface. To explain the experimentally observed electron density profiles for the CsCl solution-muscovite interface, the co-adsorption of Cs+ and Cl− ion pairs would be necessary. Two types of inner-sphere complexes and one type of outer-sphere complex were observed for hydrated Li+ ions near the muscovite surface. For Na+, K+, Cs+, and H3O+ ions, the inner-sphere complexes were stable on the muscovite surface. The density oscillation of water molecules was observed to approximately 1.5 nm from the muscovite surface. The number of peaks and the locations for the density of water oxygen atoms were almost similar among the water molecules coordinated to Li+, Na+, K+, and H3O+ ions adsorbed on the muscovite surfaces. The water molecules around Cs+ ions that were adsorbed to muscovite surfaces seemed to avoid coordinating with Cs+ ions on the surface, and the density of water oxygen near the muscovite surface decreased relative to that in a bulk state. There was no significant difference in self-diffusion, viscosity, retention time, and reorientation time of water molecules among different cations adsorbed to muscovite surfaces. These translational and rotational motions of water molecules located at less than 1 nm from the muscovite surfaces were slower than those in a bulk state. A significant difference was observed for the exchange times of water molecules around monovalent cations. The exchange time of water molecules was long around Li+ ions and decreased with an increase in the ionic radius. 相似文献