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1.
Smoothing and interpolation by kriging and with splines 总被引：1，自引：0，他引：1
G. S. Watson 《Mathematical Geology》1984,16(6):601-615
Let scalar measurements at distinct points x1, , xn
be y1, , yn.We may look for a smooth function f(x)that goes through or near the points (xi, yi).Kriging assumes f(x)is a random function with known (possibly estimable) covariance function (in the simplest case). Splines assume a definition of the smoothness of a nonrandom function f(x).An elementary explanation is given of the fact that spline approximations are special cases of the solution of a kriging problem. 相似文献
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本溪组指中国北方奥陶系灰岩不整合面之上、石炭-二叠纪含煤岩系之下,由碎屑岩夹灰岩或灰岩凸镜体所组成的一套海陆交互相地层。随着研究的深入,特别是地层学理论的发展及认识的不同,对本溪组岩石地层和年代地层的划分形成了多种争议。本文按地层多重划分的观点和方法认为组是一个岩石地层的自然实体,并有区别于相邻自然实体单位的岩石内容和反映其发育的某一特定过程。为此,建议以层型剖面(本溪市新洞沟与蚂蚁村沟间的牛毛岭)为准,将本溪组岩石地层单位定义到《全国地层多重划分对比研究》的成果上来。即奥陶系灰岩顶部不整合面之上、下蚂蚁沟灰岩底界之下的一套碎屑岩层。从该灰岩层(即华北各地下部第一层灰岩)始,到最上部一层灰岩顶界(如山西太原的东大窑灰岩、河南禹州L8灰岩)为上覆太原组。该组下部产G、F两层铝土页岩,称为湖田段;上部为紫色-杂色富碳岩系(夹一薄煤层或碳质页岩)称为新洞沟段。本溪组的地质时代或年代地层,依据各地所产化石及上覆太原组第一层灰岩(即顶界)所产化石,不同地区时限不同,在吉南-辽东地区为大塘阶-德呜阶;在晋冀鲁为罗苏阶-滑石板阶;而在河南禹州其顶界进入逍遥阶(或小独山阶)-阿瑟尔阶;明显地反映出岩石地层单位穿时的普遍性规律。 相似文献
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农业地质及其开发利用 总被引：2，自引：0，他引：2
农业是人类基本生活资料的主要来源，是国民经济发展的基础，制约着其他产业部门发展的速度和规律。中国是农业大国，但却不是农业强国，农业地质主要研究与农业有关的岩石，地貌，地球化学，水资源等地质条件，农业地质与农业生产息息相关，并为农业生产的良好发展提供依据。 相似文献
4.
Geostatistical Seismic Inversion with Direct Sequential Simulation and Co-simulation with Multi-local Distribution Functions 总被引：1，自引：0，他引：1
Rúben Nunes Amílcar Soares Leonardo Azevedo Pedro Pereira 《Mathematical Geosciences》2017,49(5):583-601
Stochastic sequential simulation is a common modelling technique used in Earth sciences and an integral part of iterative geostatistical seismic inversion methodologies. Traditional stochastic sequential simulation techniques based on bi-point statistics assume, for the entire study area, stationarity of the spatial continuity pattern and a single probability distribution function, as revealed by a single variogram model and inferred from the available experimental data, respectively. In this paper, the traditional direct sequential simulation algorithm is extended to handle non-stationary natural phenomena. The proposed stochastic sequential simulation algorithm can take into consideration multiple regionalized spatial continuity patterns and probability distribution functions, depending on the spatial location of the grid node to be simulated. This work shows the application and discusses the benefits of the proposed stochastic sequential simulation as part of an iterative geostatistical seismic inversion methodology in two distinct geological environments in which non-stationarity behaviour can be assessed by the simultaneous interpretation of the available well-log and seismic reflection data. The results show that the elastic models generated by the proposed stochastic sequential simulation are able to reproduce simultaneously the regional and global variogram models and target distribution functions relative to the average volume of each sub-region. When used as part of a geostatistical seismic inversion procedure, the retrieved inverse models are more geologically realistic, since they incorporate the knowledge of the subsurface geology as provided, for example, by seismic and well-log data interpretation. 相似文献
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Acta Geotechnica - A hyperelasticity for granular medium is proposed in this study, considering the inherent and stress-induced anisotropy. The nonlinear elastic behavior is described by defining... 相似文献
8.
Lavas and pyroclastics on Ascension Island contain plutonic blocks that include fluid-inclusion-bearing peralkaline-granite. 18O/16O ratios, F and Cl have been analysed on whole rocks and/or minerals for lavas and granites, and D/H ratios and H2O+ for comenditic obsidians and granites. Whole rock 18O/16O ratios of fresh alkali-basalt, hawaiite, trachyandesite, trachyte and comendite range from 6.0 to 6.9 with 18O tending to increase with increase in SiO2. The
18O values of the granites are from 0.0 to 0.3 depleted in 18O relative to the comendites. Comenditic obsidians have D= –80±4 and H2O+ 0.3 wt.% while amphiboles from the granites have D= –56±2 The O-isotope trend of the lavas is consistent with a crystal fractionation model. Fresh igneous rocks with
18O values greater than 7 involve processes in addition to crystal fractionation of a basaltic magma. The D/H ratios and Cl contents ( 3,000 ppm) of the H2O-poor comenditic obsidians represent undegassed primary magmatic values. The H-isotope compositions and low H2O and Cl (167 ppm) contents of the granites are consistent with the major degassing (loss of >90% of initial H2O) of an H2Osaturated magma derived from the interaction of sea (or possibly meteoric) water with the H2O-undersaturated comenditic melt. It is proposed that, associated with caldera subsidence and stoping, water was sucked in around the residual magma before the system had time to be sealed up. The H2O-undersaturated magma consumed this H2O with possibly some minor partial dehydration and dewatering of the hydrated volcanic roof blocks, at a pressure of about 1.5 kb. The granites are the plutonic equivalents of rhyolitic pyroclastics and not directly of the comendites. Granites from oceanic islands may, in general, be a result of generating an H2O-saturated acid melt by such direct or indirect crustal water-magma interaction processes.Contribution No. 603 Centre de Recherches Pétrographiques et Géochimiques 相似文献
9.
Xavier Emery 《Mathematical Geology》2003,35(6):699-718
This paper presents a methodology for assessing local probability distributions by disjunctive kriging when the available data set contains some imprecise measurements, like noisy or soft information or interval constraints. The basic idea consists in replacing the set of imprecise data by a set of pseudohard data simulated from their posterior distribution; an iterative algorithm based on the Gibbs sampler is proposed to achieve such a simulation step. The whole procedure is repeated many times and the final result is the average of the disjunctive kriging estimates computed from each simulated data set. Being data-independent, the kriging weights need to be calculated only once, which enables fast computing. The simulation procedure requires encoding each datum as a pre-posterior distribution and assuming a Markov property to allow the updating of pre-posterior distributions into posterior ones. Although it suffers some imperfections, disjunctive kriging turns out to be a much more flexible approach than conditional expectation, because of the vast class of models that allows its computation, namely isofactorial models. 相似文献
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Acta Geotechnica - The dynamics of grain fabrics is captured by means of a hidden state variable , named eutaraxy, which quantifies the propensity for a heat-like micro-seismicity due to disturbing... 相似文献
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数据光盘库及数据格式 总被引：1，自引：0，他引：1
数据光盘库课题是“深部地球物理探测数据共享与对比研究”项目下的子课题,从1998年初开始至2000年底结束。课题在各专业课题制定的专业方法数据入库技术规定的前提下,调研了各单位数据保存状态,协调提交的入库数据,并编辑,整理。利用ACCESS软件,建立一套可实现数据多种格式转换,查询,刻录,共享并可广为使用的数据光盘交换系统。同时,协调了各地球物理专业方法的数据格式,并对各种专业数据格式进行了比较研究。采用先进的计算机技术和光盘介质,刻录并保存了大量而珍贵的新老深部研究数据。 相似文献
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《Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy》1999,24(8):721-725
The model of oscillator with mass m is considered. The expression for potential energy of oscillator U = mω2x2/2 is symmetric with respect to angular frequency ω and coordinate x. Provided that in case of small ω not the mechanical angular momentum mωx2, but the force mω2x is quantizied, a wave equation of mass motion is examined. This wave equation contains a quantum of force and is examined in ω-space. Such an equation is similar to the Schrodinger equation for harmonic oscillator with Planck's constant in x-space. The wave equation with quantum of force gives the spectrum of values of oscillator energies En = Hx(n+1/2), where H is the quantum of force, n = 0,1,2,…. Theoretical estimate for gravitation force quantum H is 10−37 ÷ 10−36 N. A few results of observational cosmology can be explained by quantization of force. The model presented permits one to link directly the Newton's laws of classical mechanics and the quantum theory. Moreover, such an approach allows one to explain the frequency steps of quantum standards and also irregular globally-correlated frequency variations of standards. 相似文献
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J. Tomaszewska P. Smektała I. Zgłobicka J. Michalski K. J. Kurzydłowski P. Krzemiński C. Escudero-Oñate 《International Journal of Environmental Science and Technology》2018,15(9):1831-1842
Due to its harmful impact on human health, the presence of heavy metals, metalloids and other toxic pollutants in drinking or irrigation water is a major concern. Recent studies have proved that nanosized adsorbents are significantly more effective than their microsized counterparts. Particular attention has been given to nanocomposites with nanoadsorbents embedded in matrixes that could provide stability to the material and contribute to eliminating problems that may appear when using conventional granular systems. This study presents the preparation of a novel hybrid filter from a commercially available polypropylene (PP) non-woven fabric matrix modified with multiwall carbon nanotubes (MWCNT) and iron oxy(hydroxide) nanoparticles, and its use in the removal of As(III). A Box–Behnken statistical experimental design has been chosen to explore relevant variables affecting the filter performance: (1) As(III) concentration, (2) pH and (3) sorbent dose. From an As(III) concentration of 10 mg L?1, at pH 6.5 and with a sorbent dose of 5 g L?1, the PP filter modified with MWCNT removes 10% of the initial metalloid concentration, reaching a capacity of 0.27 mg g?1. After modification with iron oxy(hydroxide), the performance of the material is largely enhanced. The filter, under the same conditions, removes 90% of the initial As(III) concentration, reaching a capacity almost tenfold higher (2.54 mg g?1). This work demonstrates that the developed hybrid filter is effective toward the removal of As(III) in a wide range of pHs. A cubic regression model to compute the removal of the filter as a function of pH and sorbent dose is provided. 相似文献
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I. R. Plimer 《Mineralium Deposita》1980,15(3):275-289
Precambrian and Early Palaeozoic submarine exhalative Sn and W deposits are most commonly present in thick deep water sequences comprising pelites, carbonate, calcsilicate and cherty rocks, mafic volcanics and quartz-tourmaline rocks. The exhalative deposits are commonly low grade and, in places, the sequence is transgressed by granites with economic Sn or W mineralisation. These thick deep water sequences as components of sinking trenches are more likely than most other rocks to undergo high grade metamorphism and anatexis. Thus elements such as Sn, W, B, F, Mo, Bi, Li, Be and base metals associated with the exhalites rapidly partition into the anatectic melt, lower the liquidus and solidus, and are concentrated in the late stage aqueous fluids and residual melt fractions to form Sn or W deposits associated with highly fractionated granitic rocks. 相似文献
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This paper describes simulation experiments in which glucose and cellulose were reacted with polysulphide and hydrogen sulphide at ambient temperatures in an aqueous environment. Organic sulphur containing compounds were formed that yield several thiophenes upon pyrolysis/evaporation. The experiments show that interaction of carbohydrates with hydrogen sulphide or polysulphides is a possible way for carbohydrates to react in very recent sediments. From the results of this study it can be concluded that carbohydrate carbon can be preserved in sediments in a form that is resistant to microbial attack and that will have a greater potential for survival during diagenesis than the carbohydrate precursor. 相似文献
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基于GIS的湖南雨凇分布与地形因子关系分析 总被引：1，自引：1，他引：0
利用湖南省97个气象站雨凇观测资料,分析了湖南雨凇地理分布特征. 结果表明：湘南属于湖南雨凇多发区,平均雨凇日数多于湘北;湘南雨凇分布特征与山地走向一致,沿雪峰山脉呈西南-东北走向的迎风坡与沿南岭北侧的迎风坡各有一高值区;湘北平均雨凇日数2 d左右,其中,湖区平原明显多于湘北山区.结合1∶50 000湖南省DEM数据,探讨了地形高程、坡度坡向、纬度等地形因子对湖南雨凇形成的作用.在海拔200 m以下,高程的变化对雨凇影响不明显;在海拔200~1 000 m,雨凇日数随高程上升而增多;海拔高于1 000 m,雨淞日数明显多于低海拔台站. 坡向对湖南平均雨凇日数的变异有一定影响,但是坡度的影响并不显著;随着纬度的变化,湖南平均雨凇日数南北差异明显. 相似文献
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氮气加泡沫欠平衡钻井是当前国际上已经成熟的一种钻井新技术。其优点是静液柱压力低,漏失量小,携屑能力强,对油气层损害小,保证水敏性地层钻井安全;可及时发现油气层,提高单井产量;因而能够最大限度地发现和保护中、低压低渗油气藏,以获取比常规过压钻井高得多的经济效益。在大牛地气田DF1井的施工应用中,针对本工区低压、低渗、水敏的特点,使用该项技术,很好地解决了工区内使用普通泥浆造成对产层污染的问题,并取得了成功。 相似文献
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Rolf Schick 《Natural Hazards》1988,1(2):125-144
Signal characteristics and intensity patterns of volcanic tremor are discussed with regard to eruption phenomena. Although a generally valid relationship cannot be given, volcanic tremor is strongly correlated to the fluid dynamics of the volcano. A major difficulty in the interpretation of volcanic tremor is the lack of an appropriate source model. It is assumed that flow transients of quite different kinds act as seismic sources. The significant correlation of volcanic tremor to external forces (barometric pressure, rain-fall loading, earth tides) is discussed and included in a relation with magma-flow instabilities. Two-phase (liquid-gas) flow instabilities play an essential role in the origin of volcanic tremor and, possibly, in the occurrence of volcanic eruptions. A model is discussed, in which one cause of tremor is seen in self-sustained pressure oscillations following transitions between subsonic and supersonic two-phase magma flow (modified Steinberg and Steinberg model). 相似文献