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151.
何钧  陈时军 《内陆地震》1998,12(3):234-241
震后灾害损失盲场快速评估的技术方法及其计算机软件系统可在确定地震震级、震中位置和发震时间等参数后,在人员未到地震现场的情况下,快速给出该次地震对一个区域造砀 经济损失和人员伤亡的初步评估结果。选择鲁南地震重点监视防御区为评估区域,并使用该软件系统对1995年9月-20日发生在苍山的5.2级地震进行了灾害损失快速评估的实际检验。从检验结果可看出 ,用固定资产损失率矩阵计算经济损失,获得基础资料方便,  相似文献   
152.
王正尚  康英 《华南地震》1998,18(1):125-129
对1997年9月23日和26日两次三水有感地震的特征进行了初步分析,认为这两次地震具有震前和震后地震活动水平低、面波发育和低震级高烈度等特性;震区的主压应力为北北西方向,两震的受力方向基本一致,但断层面解明显不同。  相似文献   
153.
库车坳陷地质结构及油气带预测   总被引:3,自引:2,他引:1  
利用油气地震勘探成果和露头的岩性资料 ,对库车坳陷地震层序进行划分 ,初步认为第三系膏盐层和三叠 -侏罗系煤层及泥岩是分布比较稳定的区域性软弱层 ,构成了区域内的主要滑脱面。将库车坳陷划分 6个构造带 ,对库车坳陷的构造样式进行归纳总结 ,并结合典型实例 ,采用平衡地质剖面技术对重要剖面进行地质平衡解译 ,使库车坳陷地质结构更加清晰。结合该区油气成藏的地质条件 ,划分出若干油气聚集带 ,对各油气聚集带进行分别评价  相似文献   
154.
Locked in stresses,creep and dilatancy of rocks,and constitutive equations   总被引:2,自引:1,他引:2  
SummaryLocked in Stresses, Creep and Dilatancy of Rocks, and Constitutive Equations A micro rheological analysis is presented of the deformation characteristics of rocks based on the multi mineral and polycrystalline structure of igneous metamorphic and some sedimentary rocks; in addition the polygranular structure of sandstone-type rocks is also considered. Due account is taken with the history of rock formation and tectonics.Torsional creep test results on Ichang sandstone are presented and analysed. A new method of testing is introduced whereby the sample is subjected to a step wise loading function and the deformation measured as a function of the time. In this manner the creep as a function of stress and time can be obtained very easily from tests on only one sample.A hypothesis is presented on the origin and formation of locked in stresses the release of internal strain energy is studied at the hand of some typical test results. The practical importance of these stress pockets is discussed and it is stressed that creep and locked in stresses are fundamental factors in the behaviour of rocks which must be carefully studied in practice.On the basis of experimental results and physical reasoning constitutive equations are set up, which are three dimensional generalisations of the experimental Griggs equation: =a +b logt +ct, whereby the material parameters are scalar functions of the stress invariants.
ZusammenfassungRestspannungen, Kriechen und Dilatation von Gesteinen, und Ausgangsgleichungen Es wird eine Analyse der rheologischen Verformungseigenschaften von Fels gezeigt, die auf dem Mineral- und Kristallgefüge von metamorphen Erstarrungs-und einigen Sedimentgesteinen beruht; außerdem wird das Korngefüge von Gesteinen mit einem Aufbau ähnlich dem von Sandsteinen berücksichtigt. Ebenso werden Gebirgsbildungsvorgänge und Tektonik beachtet.Ergebnisse von Torsionskriechversuchen an Ichang-Sandstein werden vorgelegt und analysiert. Eine neue Versuchsmethode wird vorgestellt, wobei der Probekörper einer stufenweise gesteigerten Belastung unterworfen wird und die Verformungen als Funktion der Zeit gemessen werden. Auf diese Weise wird durch Versuche mit nur einem Probekörper das Kriechen als Funktion der Belastung und der Zeit ermittelt.Es wird eine Hypothese über den Ursprung und die Bildung von Restspannungen vorgelegt. An Hand von typischen Versuchsergebnissen wird die Freiwerdung von innerer Verzerrungsenergie untersucht und die praktische Bedeutung von Kriechvorgängen und Restspannungen betont.Basierend auf Versuchsergebnissen und physikalischen Gesetzen werden Ausgangsgleichungen aufgestellt, die Verallgemeinerungen der experimentell von Griggs gefundenen Gleichung =a +b logt +ct in 3 Dimensionen darstellen. Dabei sind die Materialparameter skalare Funktionen der Invarianten des Spannungszustandes.

RésuméFluage et dilatation des roches, contraintes figées dans le massif et relatiens de comportement On présente une analyse micro-rhéologique des caractéristiques de déformation des roches, basée sur la structure multiminérale et polycristalline des roches ignées ou métamorphiques et de quelques roches sédimentaires. La structure polygranulaire des roches du type des grès est aussi envisagée. On prend en compte l'histoire de la formation des roches et de la tectonique.Des résultats d'essais de fluage en torsion sur des grès d'Echang sont données et analysés. On présente une nouvelle méthode d'essais où l'échantillon est soumis à un chargement par échelon et où la déformation est mesurée en fonction du temps. De cette façon, le fluage en fonction des contraintes et du temps peut être obtenu très facilement à partir d'essais sur un seul échantillon.On présente une hypothèse sur l'origine et la fonction des contraintes figées dans le massif et le relachement de l'énergie de déformation est étudié au moyen de résultats d'essais typiques. L'importance pratique de ces noyaux de contraintes est discutée et l'on montre que le fluage et les contraintes figées sont des facteurs fondamentaux du comportement des roches qui doivent être étudiés avec soin dans la pratique.A partir de résultats expérimentaux et au moyen de raisonnements physiques, on établit les relations de comportement et la généralisation à trois dimensions de l'équation expérimentale de Griggs =a +b logt +ct où les paramètres du matériau sont des fonctions scalaires des invariants des contraintes.


With 8 Figures  相似文献   
155.
Investigations of atmospheric composition in the Himalayas has been limited in both temporal and spatial scales, mainly due to difficult logistics. Ideal sites for monitoring atmospheric composition and its evolution should be free from local pollution and representative of the remote troposphere (HUEBERT et al., 1980). As the Himalayas are far removed from highly industrialized regions they provide suitable locations to monitor the chemistry of the remote troposphere and to study the evolu…  相似文献   
156.
在15万区域地质调查基础上,利用花岗岩等级体制填图方法对天湖花岗岩体进行解体,建立了三个填图单元,归并为一个超单元。对各单元岩石类型、矿物成分、组构及野外接触关系进行了论述。通过岩石化学和地球化学资料论证,该岩体是同一次岩浆熔融事件过程中曾经发生过三次岩浆侵入活动而形成的环状深成岩体。  相似文献   
157.
Information about seasonal crop water consumption is useful to develop the appropriate irrigation scheme. Measurements of energy balance components using the Bowen ratio method were made for a complete growing season at a vineyard in the arid region of northwest China. Vine in the experiment was furrow‐irrigated using a trellis system. The measured evapotranspiration was compared with estimates using the soil water balance method. It is shown that the Bowen ratio method provided accurate estimates of evapotranspiration from the vineyard and this requires that the Bowen ratio system is appropriately installed. The energy balance components showed typical diurnal pattern with peaks that occurred around the midday, except for the ground heat flux which delayed its peak by 2–3 h. The sensible heat flux was greater than the latent heat flux and followed the net radiation closely. The ratio of the latent heat flux to net radiation was low in the early growing season and increased over time. Under the limited irrigation experienced in the vineyard, the latent heat flux was controlled by available soil moisture and the total evapotranspiration in the growing season was 253 mm. The seasonal progression of the crop coefficient is similar to that reported in the literature, with the maximum occurring during the month of September. The crop coefficient can be estimated as a non‐linear function of day of year (DOY) and used to estimate evapotranspiration from vineyards in the region. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
158.
1INTRODUCTIONIrrigated ricefieldsarecharacterizedbylargespatialandtemporalvariationsin CH4 emissiontotheatmo-sphere.Accordingly,thereisagreatuncertaintyintheestimate ofCH4 emissionsfromricefields.GreateffortshavebeenmadetoestimatetheCH4 emissionsfromricefieldsandseveralapproacheshavebeendeveloped.TherepresentativemethodsincludetheIPCC(Inter-governmentPanelofClimateChange)region-specificemissionfactormethodandthemodelcalculationmethod.Toimprovethecalculationaccuracy,theIPCCmethodreq…  相似文献   
159.
Recent findings on water masses, biogeochemical tracers, deep currents and basin-scale circulation in the East/Japan Sea, and numerical modeling of its circulation are reviewed. Warming continues up to 2007 despite an episode of bottom water formation in the winter of 2000–2001. Water masses have definitely changed since the 1970s and further changes are expected due to the continuation of warming. Accumulation of current data in deep waters of the East/Japan Sea reveals that the circulation in the East/Japan Sea is primarily cyclonic with sub-basin scale cyclonic and anticyclonic cells in the Ulleung Basin (Tsushima Basin). Our understanding of the circulation of intermediate water masses has been deepened through high-resolution numerical studies, and the implementation of data assimilation has had initial success. However, the East/Japan Sea is unique in terms of the fine vertical structures of physical and biogeochemical properties of cold water mass measured at the highest precision and their rapid change with the global warming, so that full understanding of the structures and their change requires in-depth process studies with continuous monitoring programs.  相似文献   
160.
Spatial variations in dimethylsulfide (DMS) and dimethylsulfoniopropionate (DMSP) were surveyed in the surface microlayer and in the subsurface waters of the low productivity South China Sea in May 2005. Overall, average subsurface water concentrations of DMS and DMSP of dissolved (DMSPd) and particulate (DMSPp) fractions were 1.74 (1.00-2.50), 3.92 (2.21-6.54) and 6.06 (3.40-8.68) nM, respectively. No enrichment in DMS and DMSPp was observed in the microlayer. In contrast, the microlayer showed a DMSPd enrichment, with an average enrichment factor (EF, defined as the ratio of the microlayer concentration to subsurface water concentration) of 1.40. In the study area, none of the sulfur components were correlated with chlorophyll a. An important finding in this study was that DMS, DMSP and chlorophyll a concentrations in the surface microlayer were respectively correlated with those in the subsurface water, suggesting a close linkage between these two water bodies. The ratios of DMS:Chl-a and DMSPp:Chl-a showed a gradually increasing trend from North to South. This might be due to changes in the proportion of DMSP producers in the phytoplankton community with the increased surface seawater temperature. A clear diurnal variation in the DMS and DMSP concentrations was observed at an anchor station with the highest concentrations appearing during the day and the lowest concentrations during the night. The higher DMS and DMSP concentrations during daytime might be attributed to the light-induced increase in both algal synthesis and exudation of DMSP and biological production of DMS. The mean flux of DMS from the investigated area to the atmosphere was estimated to be 2.06 micromo lm(-2)d(-1). This low DMS emission flux, together with the low DMS surface concentrations was attributed to the low productivity in this sea.  相似文献   
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