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1.
Floods are random phenomena that not only cause damage to the lives, natural resources and the environment, but also affect the health of people. The severity of flooding tends to increase with urbanization. Socio-economic impacts of floods depend on the area, duration and depth of inundation, population density, housing typology, construction materials of dwellings, etc. This article examines the different available methods to trace the flood damage and illustrates the methodology to explore the economic loss through social investigation in Velachery, a part of urban Chennai in India. This paper is Part I of a two-part series in which the objectives and methodology are discussed. Based on the objectives and methodology developed for the study, a comprehensive flood management strategy can be proposed for the efficient management of future flood disasters. The results of the study are discussed in Part II. 相似文献
2.
This paper (Part II) constitutes the second of a two part series todefine the seven elements of avalanche forecasting. Part I contains the first four elements which are neededto present the human issues. This paper contains the last three elements which deal mostly with thephysical issues and their use in the decision-making process. Some basic rules of applied avalancheforecasting are included here, for the first time, to illustrate physically based principleswhich are used in applied avalanche forecasting and their link to data analysis and decisions.Since the seven elements of applied avalanche forecasting are strongly connected, the reader should consultPart I (this journal issue) as a prelude to the present paper. Part II contains sections about dataand information, scale issues in time and space, decision making and errors and physical rules ofapplied forecasting. Since all seven elements of applied avalanche forecasting are connected, Part II does not stand alone. 相似文献
3.
The infrared spectra of melanoidins which were prepared from galactose and neutral and basic amino acids (at various ratios) support in general the conclusion gained in Part I of this series. A striking resemblance in the IR spectra was obtained in melanoidins which were prepared from a high ratio of sugar to amino acids (Type 1). The imprint of the amino acids was observed only in type 2 melanoidins, which are enriched with amino acids. 相似文献
4.
Results of experimental investigation and numerical simulations of the mechanical response of the saturated cemented materials are reported. Saturated as well as dry samples cored from commercially available fire bricks are used. The samples were tested in a triaxial rock cell at different initial confining pressures. The tests have been simulated using the constitutive framework proposed in Part I of this paper. The results both experimental and numerical, provide the evidence in support of the proposed stress decomposition, thereby questioning the validity of Terzaghi's principle for the considered class of materials. 相似文献
5.
Trace Element Abundance Relationships in the Multi—stage Comagmatic Fractional Crystallization and Their Applications 总被引：1，自引：0，他引：1
In this study a mathematical expression of trace element abundance relationship for the mul-ti-stage comagmatic fractional crystallization has been established ,based on geochemical studies of the Emeishan basalt-trachyte series and adjacent mafic-ultramafic layered intrusions, as well as on the avail-able data for basalt, andesite, dacite and rhyolite series in southern Andes,Chile ,which have been well documented.It is demonstrated that the abundance constant (R) for a given trace element at dif-ferent stages of fractional crystallization of a parental magma is highly variable,which can be used as a criterion to divide fractional crystallization stages. 相似文献
6.
This paper is a companion to Clark (1988; hereafter Part I) which described the evolution of the Tejeda Magmatic System (TMS), a Miocene caldera complex, Gran Canaria, Spain, based on geochronologic, paleomagnetic and field data. In this study, petrochemical data are used to corroborate the history out-lined in Part I. Geochemical discriminant analysis shows that whereas the Extra-Caldera (EC) Mogan/Fataga volcanics are separated by a composition gap, no composition gap exists within the Intra-Caldera (IC) sequence. IC ignimbrites change rapidly but progressively from pantellerites and comendites to comenditic trachytes and finally to trachytes in a 0.47 Ma time interval. Significantly, the lower pantelleritic part of the IC series is similar to the EC pantellerites (units B, C and D) as expected based on results from Part I. The appearance of a compositional gap in the EC sequence is the result of flows having been trapped within the caldera during the 0.47 Ma Mogan-Fataga transition interval. The transitional IC sequence may be geochemically modelled by mixing of Mogan comendites and Fataga trachytes. The mixing was most probably induced by the high discharge of magma from the compositionally-zoned Tejeda magma body. The rate of change in erupted composition is best explained by imagining a continuous influx of Fataga or parental Fataga magma into a chamber whose previous silicic component (Mogan composition) was no longer being replenished and that the two magmas did not convectively mix prior to eruption. Repose times between successive eruptions in the lower to middle Mogan (from P1/T1 to A) were of order 30 000 a; the upper Mogan pantellerites and comendites/comenditic trachytes (B to F?) erupted once every 125 000 years or so. The longer repose time for the upper units is consistent with their more differentiated character. 相似文献
7.
M.H. Bradbury 《Geochimica et cosmochimica acta》2009,73(4):1004-5168
Sorption edge data for Ni(II), Co(II), Eu(III) and Sn(IV) [Bradbury M. H. and Baeyens B. (2009) Sorption modelling on illite. Part I: titration measurements and sorption of Ni(II), Co(II), Eu(III) and Sn(IV), Part I] on purified Na-Illite du Puy are available from some previous work, and some new measurements for Am(III), Th(IV), Pa(V) and U(VI) are presented here. All of these sorption edge measurements have been modelled with a 2 site protolysis non-electrostatic surface complexation and cation exchange (2SPNE SC/CE) sorption model for which the site types, site capacities and protolysis constants were fixed [Bradbury M. H. and Baeyens B. (2009), Part I]. In addition, two further data sets for the sorption of Am(III) and Np(V) on Illite du Puy, obtained from the literature, were also modelled in this work. Thus, surface complexation constants for the strong sites in the 2SPNE SC/CE sorption model for nine metals with valence states from II to VI have been obtained. A linear relationship between the logarithm of strong site metal binding constants, SKx−1, and the logarithm of the corresponding aqueous hydrolysis stability constant, OHKx, extending over nearly 35 orders of magnitude is established here for illite for these nine metals. Such correlations are often termed linear free energy relationships (LFER), and although they are quite common in aqueous phase chemistry, they are much less so in surface chemistry, especially over this large range. The LFER for illite could be described by the equation: where, “x” is an integer. A similar relationship has been previously obtained for montmorillonite, thus LFERs relating to the sorption on two of the most important clay minerals present in natural systems have been established. Such an LFER approach is an extremely useful tool for estimating surface complexation constants for metals in a chemically consistent manner. It provides a means of obtaining sorption values for radionuclides for which there are no measured values and thus allows gaps in missing sorption data to be filled. An ultimate goal of this approach is to develop a thermodynamic sorption database. This could then be used in radioactive waste management performance assessment studies to calculate sorption in natural systems, and thereby replace the current usage of single solid liquid distribution coefficients (Kd values) to describe radionuclide uptake. Finally, with the data now available, the 2SPNE SC/CE sorption model can be ported into reactive transport models allowing radionuclide migration to be calculated under spatially and temporally changing conditions. 相似文献
8.
9.
Z. M. Malkin 《Astronomy Reports》2014,58(6):415-425
Corrections to the IAU 2000/2006 parameters of the theory of precession and nutation are calculated using five different series—two individual series and three combined series that have been used in the literature for this purpose. A comparison of the sets of corrections obtained using the different datasets indicates significance systematic differences between them, which often substantially exceed the corresponding random errors. At the same time, existing studies have usually used data obtained from one or two series chosen by the authors without special justification. When refining the theory of precession and nutation, it is necessary to consider and compare various available series of VLBI data if one wishes to reduce the systematic errors in an improved model. 相似文献
10.
Metamorphism of the Crystalline Basement of Central Chile 总被引：1，自引：2，他引：1
The metamorphic basement of the Cordillera de la Costa, in CentralChile, consists mainly of slate, meta-sandstone, phyllite, andmica schist but contains small quantities of greenschist. Thegreater part of the basement is comprised in the Curepto series,and is characterized by dynamo-metamorphism whose intensityincreases westward. East of this is the smaller Nirivilo series,characterized by contact metamorphism whose intensity increaseseastward toward a granodiorite batholith. At the northern endof the metamorphic belt lies the Pichilemu series, in whichthe metamorphism is dynamo-thermal and increases in intensityto the east. The rocks in the first two areas are divisibleinto zones that trend north-north-east, essentially parallelto the margin of the batholith and to the Pacific coast; butin the Pichilemu area the zoning trends north-west. In the Cureptoseries three zones were distinguished; these are, in order fromeast to west: (1) a muscovite-chlorite(-albite) slate zone,(2) a muscovite-biotite(-albite) phyllite zone, and (3) a muscovite-chlorite-albite(±garnet) schist zone. The rocks in all three zones belongto the greenschist facies; the chlorite in the third zone isbelieved to be a product of H metasomatism. In the much narrowerNirivilo area no zones were mapped, but the following eastwardsuccession of critical assemblages was recognized: (1) muscovite-biotite-chlorite-albite;(2) muscovite-biotite-chlorite-andalusite-albite; (3) biotite-muscovite-andalusite-oligoclase;(4) biotite(± muscovite)-andalusite-sillimanite (or cordierite).The muscovite in the rocks that have undergone highgrade metamorphismis largely of metasomatic origin. Part of the sillimanite hasbeen formed at the expense of biotite and andalusite. In mostof the Nirivilo area the most strongly metamorphosed rocks areof the hornblende-hornfels facies, but small parts of that areamay contain rocks of the pyroxene-hornfels facies. The Pichilemuarea comprises the following zones and subzones: (1) a biotitezone, which includes (a) a muscovite-chlorite-biotite-albitesubzone and (b) a muscovite-biotite-albite subzone; (2) a garnet-oligoclasezone; (3) a staurolite-andalusite zone; (4) a muscovite-sillimanitezone; and (5) a sillimanite-orthoclase zone which includes (a)a sillimanite-orthoclase subzone and (b) a sillimanite-orthoclase-cordierite-almandinesubzone. Some thermal metamorphism is superimposed on the regionalmetamorphism. The facies grade from the greenschist to the granuliteor intermediate between the granulite and the amphibolite facies.The three series represent different pressure conditions: theNirivilo series corresponds to a low-pressure (contact) type,Pichilemu represents a low-pressure intermediate, dynamo-thermaltype, and Curepto is a dynamothermal, high-pressure intermediatetype series. The Curepto area was affected first, the Pichilemuarea next, and the Nirivilo area last. The metamorphism in allthree series is thought to have occurred during a single tectoniccycle within Late Paleozoic time, but it was probably interruptedby periods of erosional unloading. The width of the contactaureole is thought to have been determined by the irregularexpansion of the batholith. The analogy between the metamorphicseries of the Cordillera de la Costa and Miyashiro's circum-Pacificpaired belts is briefly discussed. 相似文献
11.
12.
KEITH DUFF 《Geology Today》1985,1(2):55-57
The protection and long-term safeguarding of geological localities are fundamental to the continuation of fieldwork, both now and in the future. The responsibility for these lies with the Nature Conservancy Council, the government agency charged with protecting geological and biological sites. Part of the work of the Council's Geology Branch is concerned with creating or re-exposing geological localities which are of value for teaching or collecting; and in the article which follows, Keith Duff explains the background and methods of this work, using the recently established geological trail at Salthill Quarry in Lancashire as as example. This is the first of a series of articles which will give details of British sites developed in this way. 相似文献
13.
The thermodynamics of quadrilateral pyroxene solutions have been analysed with the ternary non-convergent site-disorder model developed in Part I. Solution parameters have been refined for this model with a non-linear least squares technique to fit experimentally determined phase equilibria for the assemblages orthopyroxene-clinopyroxene (opx-cpx), pigeonite-augite (pig-aug), and opx-pig-aug. Calculated phase relations agree, within error, with experiments. Predicted cation distributions and enthalpies of solution for opx are also in agreement with measurements. Predicted cation distributions for cpx are more disordered than indicated by most available measurements. Two types of pyroxene thermometers are presented: (a) a single-pyroxene (aug) thermometer, and (b), a two-pyroxene thermometer which approximates the temperature of an observed pig-aug or cpx-opx assemblage as that of its nearest model tieline. Pyroxene pairs from two granulite suites, whose compositions were projected to the ternary system by the method of Lindsley and Andersen (1983), yield temperatures that are 25° C higher by thermometers (a) and (b) than determined from Lindsley's (1983) graphical thermometer. Temperatures calculated for projected compositions of coexisting pig-aug are within 20° C of run temperatures in experiments by Grove and Bryan (1983). 相似文献
14.
本文从热力学基本定律出发，将复杂的成岩作用过程归结为各种不同的化学反应，从而建立了一套利用反应自由能定量确定成岩作用顺序的方法。该方法将沉积岩成岩作用历史研究从定性引向定量，使其更具理论依据，结果更可靠。利用本方法对国内外两个不同碎屑岩定量研究结果表明，这种方法获得的结果与传统方法的顺序完全一致，从而说明了该方法的良好实用性。 相似文献
15.
Part I: Chemical and structural effects of cation-exchange
Attempts were made to prepare, by appropriate exchange methods, homoionic samples of phillipsite, gismondite, harmotome, chabazite
and gmelinite containing Ba, Ca, K, Na or Li-ions. Powdered natural samples were used as starting material. All samples were
analysed chemically before and after the cation exchange. The results of the analyses demonstrated clearly that the „exchange
capacity“ depends on the method used, the structure of the zeolite and the nature of the cation involved in the exchange.
The analyses also disclosed the important fact that the ratio in Mole % of the sum of exchangeable cations: Al2O3 of the natural and of the exchanged samples is generally <1, and can be as low as 0.74. Examples are presented where cation
exchange results in a substantial change in the framework structure.
Part II: Dehydration behavior and structural changes at elevated temperatures
Samples of the natural zeolites mentioned above, and of some of their cation exchange products were dehydrated in air of controlled
humidity up to 600° C. The slopes of the weight loss curves of chabazite and gmelinite are continuous, whereas those of phillipsite,
gismondite, and harmotome show a discontinuity between 90–190° C, indicating the existence of two discrete hydrated phases
for each of these zeolites. High temperature x-ray studies of powdered samples confirmed this result. The high temperature
hydrates of phillipsite, gismondite, and harmotome persist reversibly up to approximately 230° C. At higher temperatures,
new probably anhydrous phases form. Gmelinite, at 240° C, transforms irreversibly to anhydrous gmelinite which is stable up
to >700° C. The transition was studied by single crystal techniques. The chabazite structure remains intact up to >700° C.
The absolute water content and the dehydration behavoir of the zeolites investigated are primarily dependent on the nature
of the exchange cation. The structural changes at elevated temperatures are determined by the silica alumina framework.
Part III: Hydrothermal stability* and interconversions
The stability of phillipsite, gismondite, harmotome, chabazite, gmelinite, their exchange products, and of the synthetic Linde
zeolites Faujasite and Type A was studied in the temperature range between 150° and 350° C at a constant pressure of 1000
atm of H2O. Between 180° and 260° C all examined Sodium and Calcium zeolites were metastable with respect to analcite (wairakite**).
Phillipsite and sodium-rich zeolites generally converted to analcite (wairakite) directly. Caex-chabazite and Caex-gmelinite formed phillipsite, whereas Ca-gismondite and Ca-Type A formed natrolite as intermediate phases. Li-gmelinite converted
to bikitaite***. (This represents the first successful preparation of natrolite and bikitaite. Attempts starting from gels
or glasses have been unsuccessful so far.) Ba-gmelinite converted to harmotome at 250° C. This transformation was studied
microscopically and by single crystal x-ray techniques.
The transformations that take place on hydrothermal treatment as well as on low temperature cation exchange of zeolites (see
Part I) indicate that, unlike the conditions prevailing in clays, the type of cation and the ratio of cations in the exchange
positions have an important influence on the structure of the silicaalumina-oxygen framework. This explains two phenomena:
The lack of solid solution between two potential end members of a solid solution series (for instance phillipsite-gismondite),
and the large number of different zeolites in nature, where a great variety in the ratios of available alkali and alkaline
earths ions must be expected.
Any classification of zeolites becomes still more difficult in view of the fact that conversions among different groups (chabazite
→ phillipsite) and different structures (three-dimensional framework → fibre) take place relatively easily.
Contribution No. 59–92, College of Mineral Industries, The Pennsylvania State University, University Park, Pennsylvania. 相似文献
16.
The Use of Lagrange Diagrams in Precise Initiation Blasting. Part I: Two Interacting Blastholes 总被引：2，自引：0，他引：2
Using the concept of Lagrange diagrams this contribution details the calculation of the delay time between blastholes in a row and rows of blastholes with respect to precise initiation timing within the new advanced blasting technology which is based on the use of electronic detonators. After introducing the representations of stress waves and cracks, this contribution focuses on the role of stress wave interaction in optimal fragmentation in surface blasting and bench blasting. Part I of the paper considers two interacting blast-holes, Part II will be devoted to three or more out of plane interacting blastholes, whereas Part III will treat the interaction with a free face such as encountered in bench blasting. A few simplifying assumptions have been made in this paper with respect to the rock mass as well as the mechanical treatment. The essential assumptions include that the rock mass is treated as a continuum with finite tensile and compressive strength and the effects of structural geology are not taken into account. In addition, the analysis in Part I is simplified by two 'educational' assumption, that all waves are plane (i.e., one-dimensional) waves and three-dimensional effects of finite size blastholes and charges are not taken into account. This contribution will also show that knowledge in wave propagation and fracture mechanics is essential for the successful application of the new blasting technique in industry. In particular, the delay time, the wave speeds in the rock mass, the shape of the wave pulse and the acoustic impedance mismatch (not considered in this paper) have become decisive parameters in advanced blasting. Utilizing the wave speed and wave shapes of detonations, large scale tests in various countries (Australia, Chile, etc.) have shown that optimal delay timing requires shorter delay times in conjunction with allowing for a wider drilling pattern and the use of a grossly reduced amount of explosives , i.e., a lower powder factor. This seemingly contradictory arrangement is fully justified by using scientific principles in blasting, and converting blasting from an art to a scientific discipline . 相似文献
17.
Atsushi ANDO Naoki MITA Shigeru TERASHIMA 《Geostandards and Geoanalytical Research》1987,11(2):159-166
During the five-year period (April 1981 - March 1986), a series of fifteen rock reference samples, "Igneous rock series", has been prepared by the Geological Survey of Japan (GSJ). Based on the data available (published and communicated), consensus values for major, minor and trace elements have been derived; these values are presented for this second series of samples as well as for the first series of two samples, Granodiorite JG-1 and Basalt JB-1. 相似文献
18.
Vladimir Cermak Jan Safanda Louise Bodri 《International Journal of Earth Sciences》2008,97(2):365-373
Temperature was monitored in two boreholes in Kamchatka (Russia) in years 2001–2003. Ten-min reading (sampling) interval was
selected for the first half-year run followed by shorter (12 days) experiment with 5-s reading interval. A similar experiment
was repeated later in the test borehole Sporilov (Prague, Czech Republic), where four temperature–time series were performed
with reading intervals varying from 1 to 20 s. All temperature–time series (except the record from the bottom of the hole)
displayed intermittent, non-periodic oscillations of temperature of up to several hundredths of degree with sharp gradients
and large fluctuations over all observed time intervals. No such oscillation was detected at the bottom of the hole. The spectral
analysis revealed a high level of stochasticity in the measured signal. Calculated spectra showed “band-pass” behavior without
any definite peaks, which might characterize certain periodicity. Local growth of the second moment technique revealed the
presence of at least two distinct temperature-forming processes. One of them can be related to heat transfer in the structurally
and compositionally complex subsurface. The second process, which presents the bulk of the measured signal, probably reflects
certain intra-hole convection. We hypothesized that the oscillatory regime of such convection is responsible for the stochastic
nature of measured temperatures. Results of numerical modeling describing the fluctuation of water-cells in a vertical slot
support the idea of thermally unstable water column in a hole, the instability of which produces a complex oscillation system.
Model solutions and their discussion is presented in Part II of this work. 相似文献
19.
Yongbo Gao Christoph Merz Gunnar Lischeid Michael Schneider 《Environmental Earth Sciences》2018,77(2):47
Like almost all fields of science, hydrology has benefited to a large extent from the tremendous improvements in scientific instruments that are able to collect long-time data series and an increase in available computational power and storage capabilities over the last decades. Many model applications and statistical analyses (e.g., extreme value analysis) are based on these time series. Consequently, the quality and the completeness of these time series are essential. Preprocessing of raw data sets by filling data gaps is thus a necessary procedure. Several interpolation techniques with different complexity are available ranging from rather simple to extremely challenging approaches. In this paper, various imputation methods available to the hydrological researchers are reviewed with regard to their suitability for filling gaps in the context of solving hydrological questions. The methodological approaches include arithmetic mean imputation, principal component analysis, regression-based methods and multiple imputation methods. In particular, autoregressive conditional heteroscedasticity (ARCH) models which originate from finance and econometrics will be discussed regarding their applicability to data series characterized by non-constant volatility and heteroscedasticity in hydrological contexts. The review shows that methodological advances driven by other fields of research bear relevance for a more intensive use of these methods in hydrology. Up to now, the hydrological community has paid little attention to the imputation ability of time series models in general and ARCH models in particular. 相似文献
20.
Daniel N. Leavell 《Environmental Geology》2006,50(8):1141-1149
Granville Solvents Inc. (GSI) operated for years on the Raccoon Creek flood plain in the central Ohio town of Granville, handling bulk quantities of fuels and solvents. The site is adjacent to Granville’s public water supply. The water wells of the village draw from a substantial buried-valley aquifer, which is vulnerable to surface influences and contaminants. GSI received a 3-year Resource Conservation and Recovery Act (RCRA) Part A permit without any siting evaluation because of its grandfather status, and was able to expand its operations greatly. During the expansion, continued negotiations involving permit applications and modifications were conducted; with continued disregard for site contamination. Although a Part B permit was never granted, GSI operated for 6 years under RCRA. Today the site is a Superfund operation and more than five million dollars have been spent on cleanup and maintenance of contaminated soil and groundwater. After 15 years of cleanup, the active remediation has been suspended for the present; however, management of the site for the protection of the adjacent well field is likely to continue well into the future. 相似文献