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S. I. Mayr H. Burkhardt Yu. Popov A. Wittmann 《International Journal of Earth Sciences》2008,97(2):385-399
Internal surface, formation factor, Nuclear Magnetic Resonance (NMR)-T2 relaxation times and pore radius distributions were
measured on representative core samples for the estimation of hydraulic permeability. Permeability is estimated using various
versions of the classic Kozeny–Carman-equation (K–C) and a further development of K–C, the fractal PaRiS-model, taking into
account the internal surface. In addition to grain and pore size distribution, directly connected to permeability, internal
surface reflects the internal structure (“micro morphology”). Lithologies could be grouped with respect to differences in
internal surface. Most melt rich impact breccia lithologies exhibit large internal surfaces, while Tertiary post-impact sediments
and Cretaceous lithologies in displaced megablocks display smaller internal surfaces. Investigations with scanning electron
microscopy confirm the correlation between internal surface and micro morphology. In addition to different versions of K–C,
estimations by means of NMR, pore radius distributions and some gas permeability measurements serve for cross-checking and
calibration. In general, the different estimations from the independent methods and the measurements are in satisfactory accordance.
For Tertiary limestones and Suevites bulk with very high porosities (up to 35%) permeabilites between 10−14 and 10−16 m2 are found, whereas in lower Suevite, Cretaceous anhydrites and dolomites, bulk permeabilites are between 10−15 and 10−23 m2. 相似文献
224.
Response of riparian vegetation to water-table changes in the lower reaches of Tarim River, Xinjiang Uygur, China 总被引:1,自引:0,他引:1
Yaning Chen Zhonghe Pang Yapeng Chen Weihong Li Changchun Xu Xinming Hao Xiang Huang Tianming Huang Zhaoxia Ye 《Hydrogeology Journal》2008,16(7):1371-1379
The lower reaches of Tarim River in the Xinjiang Uygur region of western China had been dried out for more than 30 years before water began to be diverted from Konqi (Peacock) River via a 927-km-long channel in year 2000, aimed at improving the riparian ecological systems. Since then, eight intermittent water deliveries have been carried out. To evaluate the response of riparian vegetation to these operations, the groundwater regime and vegetation changes have been monitored along the 350-km-long stem of the river using a network of 40 dug wells at nine transects across the river and 30 vegetation plots at key sites. Results show that the water table rose remarkably, i.e. from a depth of 9.87 m before the water delivery to 3.16 m after the third water delivery. The lateral distance of affected water table extended to 1,050 m from the riverbank after the fourth water delivery. The riparian vegetation has changed in composition, type, distribution, and growing behavior. This shows that the water deliveries have had significant effects on restoration of riparian ecosystems. 相似文献
225.
应用探地雷达探测活动断层 总被引:1,自引:0,他引:1
在浅覆盖区采用探地雷达探测地震活动断层。通过实验确定出最佳的采集参数和数据处理流程,在雷达剖面上,能够清晰地显示出断层上部的形态特征、上断点埋深和岩土分层。结合钻孔资料,利用雷达剖面上对第四系覆盖的分层结果和上断点所在的层位可以分析和评价断层的活动性。 相似文献
226.
在全面分析大雁矿业集团公司雁南煤矿北二采区的水文地质条件及煤层开采矿井充水因素的基础上,计算了开采27^1号煤层时导水裂隙带发育高度.得出了北二采区各煤层工作面开采即不会受到上部砂砾含水层的影响,雁南煤矿铁路涵洞以西的胜利河冲击沟也不会受到北二采区的采动塌陷影响的结论。 相似文献
227.
地图符号是地图的语言单位,通过对地图符号的解读,可以直观的了解地图所表达的地理信息。ArcGis的符号化功能对于测绘符号的绘制是有一定局限的。而其他大部分测图软件的符号系统基本上是针对各个软件的,不同的软件都有独立的符号系统,离开了软件平台,如不打散块状符号或不添加辅助线就不能为其它软件所调用,本文中提出的ArcSymbol插件实现了在ArcGis操作环境下无需打散或添加辅助线即可方便、快速、无损的查看和打印满足地形图图式要求的图形,减少空间数据库中的数据冗余。并且ArcSymbol支持Shape、Coverage、Geodatabase格式,不需要数据的转换就能轻松地实现图形符号化,实现符号化的无损性。 相似文献
228.
R. A. Oktyabrsky A. A. Vrzhosek A. M. Lennikov T. A. Yasnygina S. V. Rasskazov E. Yu. Moskalenko T. A. Velivetskaya 《Russian Journal of Pacific Geology》2008,2(4):325-335
New geochemical data are presented on the magmatic rocks of the Late Jurassic Koksharovka alkaline-ultrabasic massif, which is associated with deposits of vermiculite, apatite, V-bearing titanomagnetite, and placer isoferroplatinum. The REE geochemistry and strontium, oxygen, and carbon isotopic composition of carbonatites and related ijolites and pyroxenites, together with geological observations, point to the magmatic origin of the Koksharovka carbonatites. The origin of associated magmatic rocks is discussed. Trace element modeling of partial melting of mantle sources was conducted to decipher the genesis of the melts of the Koksharovka carbonatites and host titanite-kaersutite pyroxenites. 相似文献
229.
S. V. Shipunov Yu. S. Bretshtein A. V. Zhuravlev 《Russian Journal of Pacific Geology》2008,2(4):344-353
The analysis of paleomagnetic data available for the southern Primiorye region revealed that the studied objects were magnetized under regional remagnetization presumably during the Late Mesozoic folding and this magnetization can be interpreted as being synfolding. The interpretation is based on the parameter that characterizes the folding completion degree immediately before regional remagnetization. It is shown that the relaxation of Late Mesozoic horizontal stresses was irregular. The obtained estimates of the degree of folding completion are consistent with the available geological data and Talitskii’s model for tectonic deformations. 相似文献
230.
Yu. A. Kugaenko V. A. Saltykov V. I. Sinitsyn A. A. Shishkin 《Russian Journal of Pacific Geology》2008,2(3):218-227
In 2003–2004, long-term seismic noise observations were launched on Shikotan Island (Lesser Kuril Range) based on the “Shikotan” dormant regional seismic station. The geological and geophysical data on the registration area are reported. Information about the equipment and its technical specifications is given. The precursors to the strongest local earthquakesthat occurred in the Shikotan Island region in January 2005–March 2007 are identified. 相似文献