基于遥感的黄河三角洲蒸散的动态分析

Evapotranspiration (ET) is an important parameter for water resource management. Compared to the traditional ET computation and measurement methods, the ET computation method based on remote sensing has the advantages of quickness, precision, raster mapping and regional scale. SEBAL, an ET computation model using remote sensing method is based on the surface energy balance equation which is a function of net radiance flux, soil heat flux, sensible heat flux and latent heat flux. The former three fluxes can be computed through the parameters retrieved from remote sensing image, then the latent heat flux can be obtained to provide energy for ET. Finally we can obtain the daily ET. In this study SEBAL was applied to compute ET in the Yellow River Delta of China where water resource faces a rigorous situation. Three Landsat TM images and meteorology data of 1999 were used for ET computation, and spatial and temporal change patterns of ET in the Yellow River Delta were analysed.     

美国国家公园的地理信息系统(GIS)

通过介绍美国国家公园中GIS的管理与实施经验，结合我国在地质公园的GIS应用情况，达到促进我国国家地质公园及其它国家公园中的GIS应用的目的。     

伊宁吐拉苏火山盆地金矿成矿构造系统与远景评估

吐拉苏火山盆地金矿成矿构造系统由2种类型的成矿构造组成，一种是火山机构中的高角度塌陷式断裂；另一种是爆发．沉积相中的低角度水压式断裂．阿希金矿受控于弧形塌陷式断裂，其北东段坍塌强度大于南东段，最大张裂空间控制的矿体群向NE侧伏．阿希火山机构东侧的阿恰勒河组下可能隐伏着与西侧对应的高角度弧形塌陷式成矿断裂．爆发．沉积相中硅化岩型金矿受控于水压式断裂，不透水凝灰岩层圈闭富水粗火山碎屑岩层，组成压力仓构造并发生水力压裂作用．由水力压裂作用形成的层控水压式成矿断裂出现的几率，远大于后期由非成矿断裂切割抬升它们出现的几率．构造解析表明吐拉苏火山盆地2类成矿构造控制的金矿具有巨大的地质找矿潜力．     

高压下玄武岩浆的不混溶及其对双峰式火山岩的成因意义

我们在温度850～1300℃,压力1.0～3.0GPa和含约2%水的条件下的碱性玄武岩熔融实验产物中发现在高于2.0GPa压力下玄武岩熔融后的淬火产物中存在着两种不同成分的玻璃,其中一种呈褐色,另一种为浅色或无色.玻璃的电子探针分析结果表明,褐色玻璃具有相对高的MgO、FeO和相对低的SiO2、K2O、Na2O含量及Na2O＞K2O的特征.熔体的不混溶间隙与温度无明显关系,但与压力关系密切,即在大于2.0GPa的压力条件下两种玻璃的不混溶间隙突然增大.因此,由不混溶作用形成的双峰式火山岩应来自大于2.0GPa的上地幔,且是能够提供酸性端员物质以及快速上升的构造环境.这与双峰火山岩可以产生于大陆裂谷环境或主要产于俯冲带的弧后拉张环境而不是岛弧前缘一致.     

美国城市搜索与救援体系的组成及运作模式概述

美国城市搜索与救援体系是世界上最完善的体系之一，多年来在城市救灾和应对突发事件中发挥了重要作用，减轻了生命和财产的损失。文章概述了美国城市搜索与救援体系的组成、任务、运作原则和管理机构及支援机构。     

Analytical Model for Permeability Evolution in Microcracking Rock

— Analytical expressions to predict the enhancement of permeability due to stress-induced microcracking in initially low porosity rock are presented. A fracture mechanical microcrack model is employed to derive integrated effective hydraulic variables as a function of stress, which are then used to calculate the evolution of permeability using the statistically-based Dienes model. The model enables determination of permeability enhancement as a function of two loading parameters and three material parameters. Results are in reasonable agreement with experimental measurements and indicate that appreciable increases in permeability can be anticipated during brittle failure. The analytical nature of the model makes it easily incorporatable into numerical models that require quantification of the permeability evolution as a function of stress, for which there is currently no law.     

System identification of linear structures based on Hilbert–Huang spectral analysis. Part 2: Complex modes

A method, based on the Hilbert–Huang spectral analysis, has been proposed by the authors to identify linear structures in which normal modes exist (i.e., real eigenvalues and eigenvectors). Frequently, all the eigenvalues and eigenvectors of linear structures are complex. In this paper, the method is extended further to identify general linear structures with complex modes using the free vibration response data polluted by noise. Measured response signals are first decomposed into modal responses using the method of Empirical Mode Decomposition with intermittency criteria. Each modal response contains the contribution of a complex conjugate pair of modes with a unique frequency and a damping ratio. Then, each modal response is decomposed in the frequency–time domain to yield instantaneous phase angle and amplitude using the Hilbert transform. Based on a single measurement of the impulse response time history at one appropriate location, the complex eigenvalues of the linear structure can be identified using a simple analysis procedure. When the response time histories are measured at all locations, the proposed methodology is capable of identifying the complex mode shapes as well as the mass, damping and stiffness matrices of the structure. The effectiveness and accuracy of the method presented are illustrated through numerical simulations. It is demonstrated that dynamic characteristics of linear structures with complex modes can be identified effectively using the proposed method. Copyright © 2003 John Wiley & Sons, Ltd.     

攀西裂谷存在吗？

大陆裂谷以地幔上隆、岩石圈伸展、减薄、断陷和沉降为特征，伸展构造环境是大陆裂谷形成的必要条件和本质特征。中国学者以前所认为攀枝花-西昌裂谷的主要标志是海西期层状堆晶杂岩、晚二叠世峨眉山玄武岩、印支期环状碱性杂岩和晚三叠世裂谷盆地沉积。最近一系列研究成果表明攀西地区海西期-印支期构造岩浆热事件是地幔柱和岩石圈相互作用的结果，不是裂谷作用的产物。进一步对上扬子西缘二叠纪-三叠纪的沉积作用和构造特征综合分析表明攀西地区不存在裂谷盆地沉积。该区晚二叠世-中三叠世为古陆隆起遭受剥蚀，晚三叠世断陷型类磨拉石建造是前陆走滑复合盆地的产物。本文根据对攀西地区二叠纪-三叠纪的岩浆活动、沉积作用、构造特征和地球物理资料等方面综合研究对攀西裂谷的存在提出质疑，并以峨眉山地幔柱活动为主线探讨了攀西地区古生代和中生代的地质构造演化历史。     

利用卫星测高空间技术建立数字化海洋

论述了卫星测高空间技术的主要特征、科学意义及其在军事和经济建设领域的重要价值，阐明了国内外测高卫星系统的发展现状及利用卫星测高空间技术建立数字化海洋所取得的成果，分析卫星测高目前的研究方向，提出了发展我国卫星测高空间技术以及利用该技术建立数字化海洋的一些建议。     

Fluid inclusions in granulites, granulitized eclogites and garnet clinopyroxenites from the Dabie–Sulu terranes, eastern China

Minor granulites (believed to be pre-Triassic), surrounded by abundant amphibolite-facies orthogneiss, occur in the same region as the well-documented Triassic high- and ultrahigh-pressure (HP and UHP) eclogites in the Dabie–Sulu terranes, eastern China. Moreover, some eclogites and garnet clinopyroxenites have been metamorphosed at granulite- to amphibolite-facies conditions during exhumation. Granulitized HP eclogites/garnet clinopyroxenites at Huangweihe and Baizhangyan record estimated eclogite-facies metamorphic conditions of 775–805 °C and ≥15 kbar, followed by granulite- to amphibolite-facies overprint of ca. 750–800 °C and 6–11 kbar. The presence of (Na, Ca, Ba, Sr)-feldspars in garnet and omphacite corresponds to amphibolite-facies conditions. Metamorphic mineral assemblages and P–T estimates for felsic granulite at Huangtuling and mafic granulite at Huilanshan indicate peak conditions of 850 °C and 12 kbar for the granulite-facies metamorphism and 700 °C and 6 kbar for amphibolite-facies retrograde metamorphism. Cordierite–orthopyroxene and ferropargasite–plagioclase coronas and symplectites around garnet record a strong, rapid decompression, possibly contemporaneous with the uplift of neighbouring HP/UHP eclogites.

Carbonic fluid (CO₂-rich) inclusions are predominant in both HP granulites and granulitized HP/UHP eclogites/garnet clinopyroxenites. They have low densities, having been reset during decompression. Minor amounts of CH₄ and/or N₂ as well as carbonate are present. In the granulitized HP/UHP eclogites/garnet clinopyroxenites, early fluids are high-salinity brines with minor N₂, whereas low-salinity fluids formed during retrogression. Syn-granulite-facies carbonic fluid inclusions occur either in quartz rods in clinopyroxene (granulitized HP garnet clinopyxeronite) or in quartz blebs in garnet and quartz matrices (UHP eclogite). For HP granulites, a limited number of primary CO₂ and mixed H₂O–CO₂(liquid) inclusions have also been observed in undeformed quartz inclusions within garnet, orthopyroxene, and plagioclase which contain abundant, low-density CO₂±carbonate inclusions. It is suggested that the primary fluid in the HP granulites was high-density CO₂, mixed with a significant quantity of water. The water was consumed by retrograde metamorphic mineral reactions and may also have been responsible for metasomatic reactions (“giant myrmekites”) occurring at quartz–feldspar boundaries. Compared with the UHP eclogites in this region, the granulites were exhumed in the presence of massive, externally derived carbonic fluids and subsequently limited low-salinity aqueous fluids, probably derived from the surrounding gneisses.