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101.
102.
张吉汉 《地质灾害与环境保护》2008,19(1):76-78
在山西省重点地区固体废弃物现状调查研究的基础上,通过试样试验,分析研究了固体废弃物对土壤、大气、水环境的污染,探讨了对固体废弃物的治理及利用,为研究矿山生态环境地质研究提供参考,同时积累工作经验。 相似文献
103.
Mechanism for the rapid motion of the Qianjiangping landslide during reactivation by the first impoundment of the Three Gorges Dam reservoir, China 总被引:10,自引:6,他引:4
Fawu Wang Yeming Zhang Zhitao Huo Xuanming Peng Shimei Wang Shintaro Yamasaki 《Landslides》2008,5(4):379-386
The first impoundment of the Three Gorges Dam reservoir in China started from a water surface elevation of 95 m on June 1,
2003 and reached 135 m on June 15, 2003. Shortly after the water level reached 135 m, many slopes began to deform and some
landslides occurred. The Qianjiangping landslide is the largest one; it occurred on the early morning of July 14, 2003 and
caused great loss of lives and property. Field investigation revealed that, although failure occurred after the reservoir
reached 135 m, the stability of the slope was already reduced by preexisting sheared bedding planes. To study the mechanism
of the rapid motion of this reactivated landslide, two soil samples were taken from a yellow clay layer and a black silt layer
in the sliding zone, respectively, and a series of ring shear tests were conducted on the samples. One series of ring shear
tests simulates the creep deformation behavior, while the other series simulates different shear rates. Conclusions drawn
from analysis of the ring shear tests indicate that the mechanism of the rapid motion of the reactivated landslide was caused
by the rate effect of the black silt layer during the motion phase after the creep failure. The yellow clay layer did not
play any important role in the rapid motion in the 2003 event. 相似文献
104.
Martin Rosner Michael Wiedenbeck Thomas Ludwig 《Geostandards and Geoanalytical Research》2008,32(1):27-38
An analytical artefact is reported here related to differences in instrumental mass fractionation between NIST SRM glasses and natural geological glasses during SIMS boron isotope determinations. The data presented demonstrated an average 3.4‰ difference between the NIST glasses and natural basaltic to rhyolitic glasses mainly in terms of their sputtering-induced fractionation of boron isotopes. As no matrix effect was found among basaltic to rhyolitic glasses, instrumental mass fractionation of most natural glass samples can be corrected by using appropriate glass reference materials. In order to confirm the existence of the compositionally induced variations in boron SIMS instrumental mass bias, the observed offset in SIMS instrumental mass bias has been independently reproduced in two laboratories and the phenomenon has been found to be stable over a period of more than one year. This study highlights the need for a close match between the chemical composition of the reference material and the samples being investigated. 相似文献
105.
位于乌鲁木齐市南湖路以西的煤炭采空区面积达67 100.5m^2,区内构造从南到北主要由八道湾向斜和七道湾背斜组成,地层产状变化不大。该矿区开采较深,且采空区塌陷区有明显的地下水活动迹象。在对深孔大体积采空区注浆时,比较各种常见注浆治理方法,均存在不同的制约因素,故决定采用灌浆爆破压密法对采空区进行压实加固。经现场爆破试验,该区重复爆破次数在3~5次左右。灌浆爆破压密处理后,对不同土层进行取样对比分析,得到其相应密度(增加)及空隙比(减少)的变化分别为:杂填土14.1%,-7.9%;素填土5.9%,-3.3%;塌落煤层7.8%,-7.7%。根据压缩数据及现场测量,处理后的土体沉降2~4m,部分空体地段的沉降量达10~20m,治理效果明显。 相似文献
106.
In this paper, the data on the paleoclimatic and paleoenvironmental changes during the Holocene are presented and a discussion
is made on a 225-cm-long sediment core from Ulungur Lake, located in Northwest China. The chronology is constructed from six
AMS radiocarbon dates on the bulk organic matter. On the basis of the analysis of ostracod assemblages and the shell stable
isotopes, the core is divided into three paleoclimatic and paleoenvironmental evolution stages: 9 985–5 250 cal.aB.P. stage
is the wettest phase of the core section. The climate changed from moderate-dry to cool-wet, and then to warm-wet in turn,
and the lake level rose accordingly, showing the characteristic of a high lake level. 5 250–1 255 cal.aB.P. stage was the
driest phase of the core sediment. The climate turned from the early warm-dry to the late warm-wet and the lake level fell
and rose again. Finally, the 1 255 cal.aB.P. stage was the medium stage of the section. The temperature was low and then increased
after the 1920s and the climate was dry. The whole climatic and environmental evolution records of Lake Ulungur were not only
in agreement with the sporopollen record of the same core but also in agreement with the record of environmental changes of
adjacent areas. It responded to regional environmental changes and global abrupt climate events, following the westerly climate
change mode on 100-year-scale, primarily with cold-wet and warmdry characteristics.
__________
Translated from Quaternary Sciences, 2007, 27(3):382–391 [译自:第四纪研究] 相似文献
107.
塔河油田2区三叠系油藏是西北分公司开发较早的碎屑岩油藏之一,开发层系有上油组、中油组,油柱高度在15~20m,储层为辫状三角洲相辫状三角洲前缘亚相水下分流河道、河口坝、分流间湾微相沉积,非均质性严重。本区上油组砂体厚度40~0m,中油组25~35m,分布较稳定,物性为中孔、中高渗储层,原油属低粘度轻质油。但2区三叠系油藏实钻变化大,见水快、产量递减快、含水上升快、采出程度低,开发效果较差,经过多次调整虽有一定程度改善,仍存在一些问题。本文认为2区三叠系油藏开发效果较差的原因之一是对本区油藏类型的认识上存在问题即2区三叠系油藏是以断裂控制的断块油藏而非背斜油藏,并延伸分析正在投入开发评价的S96-T901井区、TK232-T453井区及T206-T208井区等都为断块(断背斜)油藏。应用断块油藏的观点对塔河地区三叠系油藏勘探开发有重要指导意义。 相似文献
108.
研究“源兆”的若干问题及途径分析 总被引:3,自引:3,他引:0
从位场理论的观点讨论了场和源的概念,建议将“场兆”改称为构造前兆,将“源兆”称为震源前兆。文中还分析了震源体与各种前兆观测方法探测的深度,并根据地磁与重力观测方法不同的物理基础和地质基础,指出震磁效应对于研究震源前兆的特殊意义,文中还介绍了1976唐山地震观测到震源前兆的部分实际地磁资料。 相似文献
109.
关于海平面上升及其环境效应 总被引:12,自引:0,他引:12
沿海地区地质环境复杂。由于国民经济的迅速发展,人类活动日益增多,对地质环境进一步造成严重的不利影响。特别是“温室效应”引发的海平面上升,使各种地质灾害更加激化。文章详细探讨了海平面上升的影响因素,理论海平面与相对海平面升降幅度的评估,以及海平面上升所造成的地质环境效应与相应的防治对策,特别强调控制沿海城市地面沉降,以减轻海平面相对上升造成的危害,具有特殊而重要的意义。 相似文献
110.
The survey for the HEIFE(Atmosphere-Land Surface Processes Experiment at Heihe River Basin,Western China) is given in the paper.The following basic subjects for land-surface processes in arid areas are studied:(1) the general characteristics of the energy budget on ground surface in arid areas;(2) the parameterization of the land surface processes;(3) the interaction between oasis and its desert circumstances,a special phenomenon in arid areas.The analysis shows that the sensible heat flux in the surface energy budget is in the majority,and the latent heat flux may be neglected.The influence of atmospheric stratification stability on the turbulent transfer of energy and substance must be considered in parameterization of land surface processes in arid areas.The "cold island effect" phenomenon in oasis and the "humidity inversion" phenomenon in desert near oasis are the result of the interaction between them.The results would improve the understanding of land surface processes in arid areas. 相似文献