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171.
以开滦集团范各庄矿某采区岩性勘探为例,介绍利用地震反演技术解决煤层顶底板岩性问题。该项技术是以测井资料作为约束条件,对地震资料进行反演,推算出波阻抗资料,进而计算煤层厚度,并对顶底板岩性作出推断。通过对部分资料验证,采用岩性反演技术解释的该采区5煤、7煤、9煤、12煤的深度、厚度及其顶底板岩性,与实际情况基本相符。 相似文献
172.
Effect of brittle fracture on the rheological structure of the lithosphere and its application in the Ordos 总被引:2,自引:0,他引:2
An empirical formula for the fracture strength of the principal rock type in the lithosphere is obtained based on the experimental data from previous studies, in which the effects of the confining pressure, size of the rock sample, temperature, strain rate and the pore pressure are taken into account, the empirical formulae for the effects of them are also presented. By comparing the frictional strength to the fracture strength calculated using the new empirical formula, it is shown that frictional sliding is dominant in the upper crust but brittle fracture is dominant in the lower part of the crust and the lithosphere beneath the crust. Therefore the fracture mechanism must be taken into account in the study of the rheological structure of the lithosphere. The empirical formula for the fracture strength is applied to study the rheological structure of the lithosphere in the Ordos block. Brittle regime in the rheological structure can be divided into two sub-regions, in one of which brittle fracture and in the other frictional sliding are dominant, respectively, unlike previous conventional studies in which frictional sliding is assumed to be the only factor; the magnitude of the rheological strength of the lithosphere calculated by the empirical formula is also lower than that obtained in previous conventional studies. 相似文献
173.
174.
Based on the theories of landscape ecology,landscape eco-environment in the coutrol watershed by reser-voir of Erlong Mountain in Heilogjiang Province was analyzed and assessed by using GIS technique and statistical model of Principal Component Analysis and Spatial Cluster Analysis.It is found that 100.08km^2(36%) of the total area is in the state of kilter,85.73km^2(31%) of the total area is in the state of general,and 47.26km^2(17%) and 15.48km^2(16%) is in the relatively poor state and ideal state.According to landscape ecological structure,there are three land-scape function areas being planned and designed.1) Agricultural landscape function area:its developmental direction is tour agriculture and high-benefit agriculture.2)Eco-environment protected function area:the direction of development and utilization of this region is to develop vigorously forest for soil and water conservation ,and try to increase the rate of vegetation cover.3)Forest landscape function area:rational cut and utilization of forest resources,space optimization disposal of category of forest ,foster of forest and protection of wildwood will become the main development directions for this region.This study trys to provide scientific foundation for ecological restoration of the whole valley and its sustain-able development. 相似文献
175.
Hao-Ting Dai Jing-Jing Zang Ying Wang Chuan-Ning Luo Yun-Long Zhang Zhi-Yong Zhang Yi-Feng Wei Li-Bo Wu Cheng-Ming Liu Cong Zhao Xiao-Lian Wang Zi-Zong Xu Guang-Shun Huang 《天文和天体物理学研究(英文版)》2022,(3):115-121
A method of identifying positron/electron species from the cosmic rays was studied in the DArk Matter Particle Explorer(DAMPE)experiment.As there is no onboard ... 相似文献
176.
黄海春季和秋季中华哲水蚤脂类含量及组成分析 总被引:2,自引:0,他引:2
脂类物质在哲水蚤的休眠、繁殖以及个体发育过程中发挥着重要作用,通过分析2010年11月(秋季)和2011年4月(春季)黄海中华哲水蚤Calanus sinicus的脂类组成,对脂类各组分的生理功能进行了初步探讨。结果表明,春季、秋季中华哲水蚤雌体脂类平均含量占干质量的10.6%和12%,C5期个体脂类含量偏高,占到干质量的17%。中华哲水蚤所含脂类主要由蜡脂和磷脂组成,两种脂类约占总脂的90%,三酰甘油含量约占总脂的6%。结合种群结构对脂类的生理作用进行了初步探讨,发现:(1)蜡脂作为主要的能量储存方式,其含量变化反映出不同发育期、不同季节中华哲水蚤的能量需求变化;(2)磷脂作为结构性脂类在中华哲水蚤个体生长与生殖过程中具有重要作用;(3)三脂酰甘油在中华哲水蚤中的含量不高,但是可能在脂类转化利用过程中发挥作用。 相似文献
177.
178.
Chemical characterization of naturally weathered oil residues in the sediment from Yellow River Delta, China 总被引:2,自引:0,他引:2
With its close proximity to Shengli Oilfield, China’s second largest oilfield, the Yellow River Delta is at high risk for crude oil contamination. The massive oil discharge in oilfield may offer a chance for a natural experiment to investigate compositional changes of oil residues and study the stability of source- and weathering-dependent molecular parameters in oil residues after spills. The results demonstrate that the conventional diagnostic ratios, such as C2920S/(20S + 20R), C29/C30H, C30βα/αβ, C3122S/(22S + 22R), C2-DBTs/C2-PHENs, C3-DBTs/C3-PHENs, DBT/MCHRY, CHRY/PHENs, are also valid for oil source identification even after extensive weathering of spilled oils in terrestrial environment, although some exceptions were encountered for extensively weathered sample. Moreover, the ratios of selected specific biomarkers (the oleanane index, the gammacerane index) have been developed and assessed as source indicators. Finally, we find that some maturity parameters based on alkyl naphthalenes and methyl phenanthrenes in petroleum geochemistry, such as the methylnaphthalene ratios (TMNr, TeMNr, PMNr), the methylphenanthrene ratios (MPI-1, MPDF), can be applied for the source identification and correlation at their lightly to moderately weathered stage. 相似文献
179.
Junguo Liu Chuanfu Zang Shiying Tian Jianguo Liu Hong Yang Shaofeng Jia Liangzhi You Bo Liu Miao Zhang 《Global Environmental Change》2013,23(3):633-643
China's water policies in the past decades have relied heavily on the construction of massive water conservancy projects in the form of dams and reservoirs, water transfer projects, and irrigation infrastructure. These facilities have brought tremendous economic and social benefits but also posed many adverse impacts on the eco-environment and society. With the intensification of water scarcity, China's future water conservancy development is facing tremendous challenge of supporting the continuous economic development while protecting the water resources and the dependent ecosystems. This paper provides an overview of China's water conservancy development, and illustrates the socioeconomic, environmental and ecological impacts. A narrative of attitude changes of the central government towards water conservancy, as well as key measures since the 1950s is presented. The strategic water resources management plan set by the central government in its Document No. 1 of 2011 is elaborated with focus on the three stringent controlling “redlines” concerning national water use, water use efficiency and water pollution and the huge investments poised to finance their implementation. We emphasize that realizing the goals set in the strategic plan requires paradigm shifts of the water conservancy development towards maximizing economic and natural capitals, prioritizing investment to preserve intact ecosystems and to restore degraded ecosystems, adapting climate change, balancing construction of new water projects and rejuvenation of existing projects, and managing both “blue” (surface/groundwater) and “green” water (soil water). 相似文献
180.
对大兴安岭中段扎赉特旗地区满克头鄂博组火山岩进行了锆石U-Pb年龄和地球化学研究。用LA-ICP-MS测得流纹质隐爆角砾岩(TW6)和流纹岩(TW14)中锆石的~(206)Pb/~(238)U年龄分别为157.2±1.2Ma和154.8±1.1Ma,表明火山岩形成于晚侏罗世。岩石地球化学特征表明,火山岩富硅碱、贫钙镁,为过铝质钙碱性系列;(La/Yb)_N=20.24~22.68,轻、重稀土元素分馏明显;球粒陨石标准化稀土元素配分模式图呈右倾形式,Eu为正异常;原始地幔标准化蛛网图显示,大离子亲石元素Rb、K相对富集,高场强元素Nb、Ti、P强烈亏损,显示壳源岩浆的特征。综合本区火山岩的特征并结合他人研究成果,认为扎赉特旗地区满克头鄂博组火山岩的形成与蒙古-鄂霍次克洋闭合后伸展作用关系密切。 相似文献