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101.
Assimilation systems absorb both satellite measurements and Argo observations. This assimilation is essential to diagnose and evaluate the contribution from each type of data to the reconstructed analysis, allowing for better configuration of assimilation parameters. To achieve this, two comparative reconstruction schemes were designed under the optimal interpolation framework. Using a static scheme, an in situ-only field of ocean temperature was derived by correcting climatology with only Argo ... 相似文献
102.
Eclogite is essentially a bi-mineralogic high-grade metamorphic rock consisting of garnet and omphacite and is the product of high-to-ultrahigh pressure metamorphism of basaltic rocks due to the subduction of oceanic crust or the thickening/subduction of … 相似文献
103.
三江平原沼泽湿地时空动态特征 总被引:3,自引:0,他引:3
1IntroductionThe wetland ecosystem is the latest one understood by humans and it is the most seriously damaged ecosystem (Williams, 1991). The Sanjiang Plain, located in northeast China, is the largest concentrated area of freshwater wetland in China. Since the 1950s, large-scale reclamation of the marsh in the Sanjiang Plain has been started. According to statistics, the natural marsh has lost about 80% of its total area. The marsh resources in the Sanjiang Plain decreased greatly and the… 相似文献
104.
纳米级超高压相金红石——大陆深俯冲深度的示踪 总被引:4,自引:0,他引:4
大陆深俯冲深度对于了解大陆碰撞造山带中超高压变质岩的折返动力学具有重要意义。文章重点综述了德国含金刚石片麻岩纳米级超高压相 α PbO2 型、斜锆石 (ZrO2 )型结构TiO2 以及金红石其它多形的超显微构造特征、形成的温度压力条件、相变机理以及动力学意义。中国大别—苏鲁超高压变质地区广泛发育金红石副矿物、金红石包裹体或针状金红石出溶体 ,它们为超高压纳米相α PbO2 型和斜锆石型结构TiO2 的存在提供了必要的物质前提。纳米新技术在地球科学中的应用 ,必将给地球科学的发展带来的契机。 相似文献
105.
According to the experimental studies on the rheology of two important mantle rocks (eclogite and harzburgite), the rheological properties of the deep subducted oceanic lithosphere are investigated by assuming a simplified harzburgite type slab model with moderate thickness of basaltic layer. When the mantle convergence rate is small or the subducting slab has been trapped in the mantle for an enough long time, the strength profile of the slab is characterized by a strong subducting crustal component lying on a weak subducting upper mantle. However, if the convergence rate is large enough, the subducting slab will be featured only by a rigid cold center. Our study suggests that the detachment of the subducting crust component from the underlying upper mantle is only likely to happen in hot slow subducting slabs, but not the cold fast subducting lithosphere. Rheological properties of the harzburgitic and the eclogitic upper mantle vary with depths. The eclogitic upper mantle is stronger than the peridotitic upper mantle across the upper mantle. Transition zone is the high strength and high viscosity layer in the upper mantle except the lithosphere. 相似文献
106.
采用透射电镜对辉长岩塑性变形过程中产生的熔体进行了研究,结果表明,在950~1000℃时出现初熔,初熔熔体呈薄膜状分布于两个斜长石边界,或者呈三角形状分布于3个斜长石之间. 这种早期熔体的SiO2含量在60髎左右. 在1050℃时,熔融程度增加,熔体不仅出现在斜长石之间,也出现在斜长石与辉石或磁铁矿之间. 熔体的SiO2含量低于50髎. 斜长石之间的熔体薄膜随熔体含量增加而变宽,把孤立的熔体三角形贯通,形成彼此连通且定向排列的熔体三角形. 这可能是在构造差应力作用下熔体向应力小的方向运移和聚集的结果. 这些熔体中有许多均匀分布的0.1~0.2μm的暗色“小球”,暗色 “小球”周边的硅酸盐熔体富硅贫铁,SiO2含量超过70髎,而暗色“小球”成分富铁贫硅,SiO2含量低于40髎,这表明熔体发生了分异. 其中富铁贫硅熔体局部发生了结晶作用,形成了树枝状磁铁矿雏晶. 熔体成分分异使富铁成分从玄武岩浆中分离,这对磁铁矿富集成铁矿起到重要作用. 相似文献
107.
A hail process in Huaihe River Basin observed by CINRAD Doppler radar on 12May 2000 hasbeen simulated by using nonhydrostatic mesoscale numerical model MM5.The simulated wind fieldis analyzed and compared with Doppler radar wind data,both of them show that there was ameso-β cyclone around the hail region.Results show that this meso-β cyclone existed below 3 kmin the troposphere and its cyclonic circulation was very obvious below 1 km.The temperature andmoisture fields from the simulation are also analyzed.Furthermore,the storm-relativeenvironmental helicity and CAPE(convective available potential energy)are discussed. 相似文献
108.
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110.
Hou Jianjun Bai Taixu Liang Haihua Zheng Wentao and Wang ShiminDepartment of Geology Peking University Beijing China 《中国地震研究》1995,(3)
Based on field observations and mechanic analysis,the authors think that synthetic faults,antithetic faults,and hangingwall cross-faults are formed on the piedmont alluvial-pluvial plain under the action of hangingwall blocks sliding downward and rotating along concave fault planes of the listric normal fault on the southeastern margin of Weihe Basin.The characteristics of different movements and expressions on the surface of these structures may be taken as the main marks for listric normal fault segmentation. 相似文献