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971.
区域地下水信息管理系统研究 总被引:2,自引:0,他引:2
本文通过《河南省地下水动态信息管理系统》的建立,讨论了区域地下水信息管理系统的设计目标,数据结构和软件实现,着重介绍了系统的软件设计特点,最后指出了这种管理系统在水文地质部门中具有广泛的应用前景。 相似文献
972.
Biomass burning in the tropical savannas of Ivory Coast: An overview of the field experiment Fire of Savannas (FOS/DECAFE 91) 总被引:1,自引:0,他引:1
J. P. Lacaux J. M. Brustet R. Delmas J. C. Menaut L. Abbadie B. Bonsang H. Cachier J. Baudet M. O. Andreae G. Helas 《Journal of Atmospheric Chemistry》1995,22(1-2):195-216
FOS/DECAFE 91 (Fire of Savannas/Dynamique et Chimie Atmosphérique en Forêt Equatoriale) was the first multidisciplinary experiment organized in Africa to determine gas and aerosol emissions by prescribed savanna fires. The humid savanna of Lamto in Ivory Coast was chosen for its ecological characteristics representative of savannas with a high biomass density (900 g m–2 dry matter). Moreover the vegetation and the climate of Lamto have been studied for more than twenty years. The emission ratios (X/CO2) of the carbon compounds (CO2, CO, NMHC, CH4, PAH, organic acids and aerosols), nitrogen compounds (NOx, N2O, NH3 and soluble aerosols) and sulfur compounds (SO2, COS and aerosols) were experimentally determined by ground and aircraft measurements. To perform this experiment, 4 small plots (100×100 m) and 2 large areas (10×10 km) were prepared and burnt in January 1991 during the period of maximum occurrence of fires in this type of savanna. The detailed ecological study shows that the carbon content of the vegetation is constant within 1% (42 g C for 100 g of vegetal dry matter), the nitrogen content (0.29 g N for 100 g of dry matter) may vary by 10% and the sulfur content (0.05 g S/100 d.m.) by 20%. These variations of the biomass chemical content do not constitute an important factor in the variation of the gas and particle emission levels. With the emission ratios characteristic of humid savanna and flaming conditions (CO/CO2 of 6.1% at the ground and 8% for airborne measurements), we propose a set of new emission factors, taking into account the burning efficiency which is about 80%: 74.4% of the carbon content of the savanna biomass is released to the atmosphere in the form of CO2, 4.6% as CO, 0.2% as CH4, 0.5% as NMHC and 0.7% as aerosols. 17.2% of the nitrogen content of the biomass is released as NOx, 3.5% as N2O, 0.6% as NH3 and 0.5% as soluble aerosols. 相似文献
973.
S. H. Derbyshire 《Boundary-Layer Meteorology》1995,75(1-2):1-24
As argued in Part I (Derbyshire, 1995), variability is a key issue in stable boundary layers, and differences in variability between observations and idealized models may imply sytematic biases. Here we discuss how data analysis can be geared to allow for variability and thus consistency with models. Instrumental errors, smoothing methods and vertical discretization are considered. We then show how statistical averaging broadly improves the agreement of heterogeneous results in Part I with the Brost-Wyngaard closure. Recommendations are made for the information needed to analyze apparent differences between homogeneous and heterogeneous stable boundary layers.Part of UK Meteorological Office Atmospheric Processes Research Division 相似文献
974.
Particulate content of savanna fire emissions 总被引:9,自引:0,他引:9
Hélène Cachier Catherine Liousse Patrick Buat-Menard Annie Gaudichet 《Journal of Atmospheric Chemistry》1995,22(1-2):123-148
As part of the FOS-DECAFE experiment at Lamto (Ivory Coast) in January 1991, various aerosol samples were collected at ground level near prescribed fires or under local background conditions, to characterize the emissions of particulate matter from the burning of savanna vegetation. This paper deals with total aerosol (TPM) and carbon measurements. Detailed trace element and polycyclic hydrocarbon data are discussed in other papers presented in this issue.Near the fire plumes, the aerosols from biomass burning are primarily of a carbonaceous nature (C%70% of the aerosol mass) and consist predominantly of submicron particles (more than 90% in mass.) They are characterized by their organic nature (black to total carbon ratio Cb/Ct in the range 3–20%) and their high potassium content (K/Cb0.6). These aerosols undergo aging during their first minutes in the atmosphere causing slight alterations in their size distribution and chemical composition. However, they remain enriched in potassium (K/Cb=0.21) and pyrene, a polycyclic aromatic hydrocarbon, such that both of these species may be used as tracers of savanna burning aerosols. We show that during this period of the year, the background atmosphere experiences severe pollution from both terrigenous sources and regional biomass burning (44% of the aerosol). Daynight variations of the background carbon concentrations suggest that fire ignition and spreading occur primarily during the day. Simultaneous TPM and CO2 real-time measurements point to a temporal and spatial heterogeneity of the burning so that the ratio of the above background concentrations (TPM/CO2) varies from 2 to 400 g/kg C. Smoldering processes are intense sources of particles but particulate emissions may also be important during the rapidly spreading heading fires in connection with the generation of heavy brown smoke. We propose emission factor values (EF) for aerosols from the savanna biomass burning aerosols: EF (TPM)=11.4±4.6 and 69±25 g/kg Cdry plant and EF(Ct)=7.4±3.4 and 56±16 g C/kg Cdry plant for flaming and smoldering processes respectively. In these estimates, the range of uncertainty is mostly due to the intra-fire variability. These values are significantly lower than those reported in the literature for the combustion of other types of vegetation. But due to the large amounts of vegetation biomass being burnt in African savannas, the annual flux of particulate carbon into the atmosphere is estimated to be of the order of 8 Tg C, which rivals particulate carbon emissions from anthropogenic activities in temperate regions. 相似文献
975.
Early miocene post-collisional calc-alkaline magmatism along the easternmost segment of the periadriatic fault system (Slovenia and Croatia) 总被引:1,自引:0,他引:1
Dr. R. Altherr Dr. B. Lugović Dr. H. -P. Meyer Dr. V. Majer 《Mineralogy and Petrology》1995,54(3-4):225-247
Summary Early Miocene calc-alkaline igneous rocks from the easternmost segment of the Periadriatic fault system can be subdivided into two series of different alkalinity: (1) Volcanics which occur in the vicinity of the Velenje-Rogatec Line range from high-alumina basalt via low-K and medium-K andesites to medium-K dacites. (2) In the Pohorje Mountains mafic rocks are lacking. A high-K tonalitic pluton crystallized at pressures of about 0.7 GPa as indicated by Al-in-hornblende barometry and accessory magmatic epidote. Rapid exhumation of the tonalite during dextral transtension along the Periadriatic fault system is indicated by tonalitic pebbles in Helvetian (?) clastic sediments. High-K andesitic to dacitic volcanics are interlayered with, and dikes cut, the clastic sediments.Compositional variations shown by the volcanics from the Velenje-Rogatec Line are consistent with fractionation of the observed phenocryst assemblages (olivine, plagioclase, clinopyroxene, orthopyroxene, titanomagnetite). Substantial fractionation of plagioclase is indicated by decreasing Sr/Nd and Sr/Y values and increasing negative Eu anomalies with increasing SiO2. All samples have chondrite-normalized HREE > 9.6 and low (Tb/Yb)n ratios (1.29–1.08). With increasing SiO2, the abundances of HREE and Y (18 to 39 ppm) increase and those of Sc (32.5 to 20.9 ppm) decrease slightly. These features, together with low Hf/Lu and Zr/Y values (10.1–5.7 and 5.7–3.6, respectively), rule out garnet as a major fractionating phase. Since (La/Yb)n values (3.24–6.59) do not increase with SiO2 and chondrite-normalized REE patterns do not show concave-upward shapes, fractionation of amphibole was probably insignificant. Although Rb/Cs values ( 18) are generally low, a significant contribution by continental crustal materials to the magmas by an AFC process is suggested by negative correlations of Nb/U(7.16 to 3.14) and Nb/Th(2.14 to 0.87) values with SiO2, as well as by low Hf/Ta(7.8–3.4), and in part also by K/Rb (340-71) and Zr/Rb (5.0–1.7) values.Rocks from the Pohorje Mountains have high abundances of U. Values of Nb/U and Nb/Th are low (3.55 to 1.85 and 1.27 to 0.64, respectively) and are negatively correlated with SiO2. These features, in combination with high values of Ba/Nb (56 to 93), Ba/La (23–30), and Rb/Cs (19–56), as well as with previously published 18O values ( 9) for the tonalite indicate a substantial contribution of the continental crust to these magmas. High Sr abundances (455 to 984 ppm) and moderate negative Eu anomalies suggest that fractionation of plagioclase was of minor importance. Although the rocks have relatively low Sc (9.3 to 3.8 ppm) and Y (21 to 14 ppm) contents, low (Tb/Yb)n values (1.67–1.14) indicate that garnet was not a major fractionating phase. Instead, fractionation of amphibole is a viable mechanism to explain the combination of high (La/Yb)n (21.8–13.1) and low (Tb/Yb)n.
With 9 Figures 相似文献
Untermiozäner, kalkalkaliner Post-Kollisions-Magmatismus entlang des östlichsten Segmentes des periadriatischen Störungssystems (Slowenien und Kroatien)
Zusammenfassung Untermiozäne Kalkalkali-Magmatite aus dem östlichen Bereich des Periadriatischen Lineaments gliedern sich in zwei Serien unterschiedlicher Alkalinität: (1) Entlang der Velenje-Rogatec-Linie treten High-Al-Basalte, Low-K- und Medium-K-Andesite und Medium-K-Dazite auf. (2) Im Pohorje-Gebirge, wo basische Magmatite fehlen, kristallisierte ein High-K-Tonalit bei Drücken von ca. 0.7 GPa (Al-in-Hornblende-Barometer, magmatischer Epidot). Gerölle dieses Tonalits in einer untermiozänen (Helvet?) klastischeu Abfolge belegen eine schnelle Heraushebung des Tonalits durch dextrale Transtension im östlichsten Bereich des periadriatischen Lineaments. Eingeschaltet in die klastischen Sedimente sind andesitische bis dazitische Pyroklastika und Laven sowie diskordante dazitische Gänge, die alle der High-K-Serie angehören.Die chemische Variation innerhalb der Vulkanitserie von der Velenje-Rogatec-Linie läßt sich durch Fraktionierung der Einsprenglingsminerale Olivin, Plagioklas, Klinopyroxen, Orthopyroxen und Titanomagnetit erklären. Abnehmende Sr/Nd- und Sr/Y-Werte und zunehmende negative Eu-Anomalien mit steigendem SiO2 weisen auf eine bedeutende Plagioklas-Fraktionierung hin. Alle Vulkanite besitzen hohe Gehalte an schweren Seltenen Erden (chondritnormiert > 9.6) und geringe (Tb/Yb)n-Werte (1.29–1.08). Mit zunehmendem SiO2 nehmen die Gehalte an Yb(2.02 bis 4.30 ppm) und Y(18 bis 39 ppm) zu, während die Sc-Gehalte (32.5 bis 20.9 ppm) nur geringfügig abnehmen. Diese Charakteristika, zusammen mit geringen Hf/Lu- und Zr/Y-Werten (10.1–5.87 bzw. 5.7–3.6), schließen Granat als wesentliche, fraktionierende Phase aus. Da die (La/Yb)n-Verhältnisse (3.24–6.59) nicht mit SiO2 korrelieren und die chondritnormierten SeltenenErden-Muster keine nach oben konkaven Formen aufweisen, spielte die Fraktionierung von Amphibol keine wesentliche Rolle. Trotz geringer Rb/Cs-Werte ( 18) wird eine beträchtliche krustale Kontamination der Magmen angenommen. Für einen AFC-Prozeß sprechen negative Korrelationen von Nb/U(7.16–3.14) und Nb/Th(2.14–0.87) mit SiO2 (bei steigenden Nb-, U- und Th-Gehalten), geringe Hf/Ta-Werte (7.8–4.3) und teilweise auch geringe K/Rb- (340-71) und Zr/Rb-Verhältnisse (5.0–1.7).Die Magmatite des Pohorje-Gebirges weisen hohe U-Gehalte sowie geringe Nb/U-und Nb/Th-Verhältnisse auf (3.55–1.85 bzw. 1.27–0.64), die eine schwache negative Korrelation mit SiO2 zeigen. Zusammen mit hohen Ba/Nb-(56–93), Ba/La-(23-30) und Rb/Cs-Verhältnissen (19–56) sowie bereits publizierten 8O-Werten ( 9) weisen diese Eigenschaften auf einen beträchtlichen Anteil assimilierten Krustenmaterials in den Magmen hin. Hohe Sr-Gehalte (455–984 ppm) und relativ geringe negative Eu-Anomalien machen es unwahrscheinlich, daß während des AFC-Prozesses in der Unterkruste wesentliche Mengen an Plagioklas fraktioniert wurden. Obwohl die Gehalte an Sc (9.3–3.8 ppm) und Y (21–14 ppm) relativ gering sind, scheidet Granat aufgrund der geringen (Tb/Yb)n- Verhältnisse (1.67–1.14) als dominierende Fraktionierungsphase aus. Die Kombination von hohen (La/Yb)n- Verhältnissen (21.8–13.1) und geringen (Tb/Yb)n-Verhältnissen deutet eher auf Amphibol als wichtige, fraktionierende Phase hin.
With 9 Figures 相似文献
976.
P. Černý R. Chapman J. Staně M. Nová H. Baadsgaard M. Rieder M. Kavalová L. Ottolini 《Mineralogy and Petrology》1995,55(1-3):177-201
Summary The chemistry, structural parameters, polytypism, optical properties and Rb-Sr isotopes were examined in 11 to 60 samples of biotite, muscovite and lepidolite from the pegmatites at Roná (the type locality of lepidolite; 323 ± 4Ma) and Dobrá Voda (306 ± 9Ma) in western Moravia. At both localities, early endocontact biotite is followed inwards by muscovite and lepidolite, which is concentrated in and around the core. At Roná, a 1M lepidolite follows after 2M1 muscovite but all later generations of lepidolite are 2M2, close to Tri50 Ply50 and in part associated with muscovite 2M1. At Dobrá Voda, all lepidolite types are 1M and free of muscovite, and the late varieties approximate Tri30 Ply70. At both localities, a trend of increasing HF is indicated during the progress of mica crystallization, culminating in precipitation of topaz. Polytypism of lepidolite is not correlatable with any compositional or growth feature, or their combination. Throughout the mica crystallization, Rb/Cs decreases but K/Rb becomes reversed after an initial decrease. Boron is partitioned preferentially into muscovite (up to 1.10 wt.% B2O3) but Be, Zn, Mn and Sc are enhanced in lepidolite. A slight increase in Fe, Ba and Cl in the last generation of lepidolite might be possibly due to mixing of residual pegmatite fluids with metamorphic pore solutions.
With 9 Figures 相似文献
Geochemische und strukturelle Entwicklung der Glimmer in den Pegmatiten von Roná und Dobrá Voda, Tschechische Republik
Zusammenfassung In 11 bis 60 Proben von Biotit, Muskovit und Lepidolith aus den Pegmatiten von Roná (Typlokalität des Lepidoliths; 323 ± 9 Ma) in Westmähren wurden Chemie, Struktur-parameter, Polytypie, optische Eigenschaften und Rb-Sr-Isotopie untersucht. An beiden Lokalitäten wird früher Biotit an Endokontakten nach Innen von Muskovit und Lepidolith gefolgt, letzterer ist in und um den Kern konzentriert. In Roná folgt 1M-Lepidolith auf 2M1-Muskovit, aber alle späteren Lepidolithgenerationen sind 2M2, nahe Tri50Ply50 und zum Teil mit 2M1-Muskovit vergesellschaftet. In Dobrá Voda sind alle Lepidolithe vom Typ 1M und frei von Muskovit, die späten Varietäten kommen Tri50Ply50 nahe. An beiden Lokalitäten ist während des Fortschreitens der Glimmerkristallisation eine Tendenz von steigendem HF angezeigt, die in der Ausfällung von Topas ihren Höhepunkt findet. Die Polytypie des Lepidoliths kann nicht mit irgendeiner Eigenheit der Zusammensetzung oder des Wachstums korreliert worden, auch nicht mit einer Kombination von diesen. Während der ganzen Glimmerkristallisation nimmt Rb/Cs ab, aber die Tendenz von K/Rb ändert sich nach anfänglichem Abfall. Das Bor verteilt sich bevorzugt auf den Muskovit (bis zu 1.10 Gew. -% B2O3), aber die Be-, Zn-, Mn- und Sc-Gehalte sind im Lepidolith erhöht. Ein leichter Ansteig von Fe, Ba und Cl in der letzten Lepidolithgeneration könnte vielleicht durch eine Mischung von pegmatitischen Restlösungen mit metamorphen Porenlösungen verursacht sein.
With 9 Figures 相似文献
977.
Abdallah I. Husein Malkawi Robert Y. Liang Jamal H. Nusairat Azm S. Al-Homoud 《Natural Hazards》1995,12(2):139-151
Earthquake hazard maps for Syria are presented in this paper. The Peak Ground Acceleration (PGA) and the Modified Mercalli Intensity (MMI) on bedrock, both with 90% probability of not being exceeded during a life time of 50, 100 and 200 years, respectively are developed. The probabilistic PGA and MMI values are evaluated assuming linear sources (faults) as potential sources of future earthquakes. A new attenuation relationship for this region is developed. Ten distinctive faults of potential earthquakes are identified in and around Syria. The pertinent parameters of each fault, such as theb-parameter in the Gutenberg-Richter formula, the annual rate
4 and the upper bound magnitudem
1 are determined from two sets of seismic data: the historical earthquakes and the instrumentally recorded earthquake data (AD 1900–1992). The seismic hazard maps developed are intended for preliminary analysis of new designs and seismic check of existing civil engineering structures. 相似文献
978.
979.
本文在《中国震例》资料基础上,详细分析了华北地区17次中强以上地震前的短临异常,得到华北地区中强以上地震短临异常的三个综合特征,在归纳出短临异常综合特征的基础上,提出了两个判定孕震过程、前兆异常由中期向短期过渡的定量的综合标志。据中期异常的追踪分析和短临异常综合分析相结合的原则,定义并计算了综合预报指标S值,以此值作为是否发生中强以上地震的判据。本文的重点是在分析短临异常综合特征的基础上,结合实用 相似文献
980.
论述了适用于遥测地震台网大震速报的一套计算机处理系统,系统设计以《全国遥测台网观测技术规范》和《近震分析》理论为依据,实现了数据输入,震相选择,数据处理,地震定位,震级计算,结果输出及贮存等多项功能,达到了快速确定地震三要素,提高速报速度和精度之目的,是一个较完善的,实用的速报系统。 相似文献