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1.
"5.12"汶川地震触发了大量地质灾害,同时形成了大量震裂松动岩体,这些岩体除受控于自身节理裂隙和结构面,还受控于地震裂缝.极震区软岩崩塌十分发育,震裂斜坡岩体损伤大,借助西部交通科技项目和国家自然科学基金展开了对软岩崩塌的研究.基于对区域工程地质条件和震裂软岩裂隙和结构面组合的调查,阐述了崩塌危岩体的变形特征,进而采...  相似文献   

2.
宝兴县潘族组崩塌位于"5.12"汶川地震重灾区四川省宝兴县,地震诱发多处危岩体崩塌失稳,造成崩塌滚石地质灾害。受地震效应作用,危岩体后缘拉裂隙逐渐被贯通,形成抛射型崩塌模式。滚石运动路径主要受滚石形状、起始运动方式、坡面特征和坡体形态等因素的影响。通过调查滚石与坡面碰撞留下的地质痕迹,真实复原了滚石运动路径。依据坡度、...  相似文献   

3.
1948年10月9日至10日,在贵州省威宁县石门乡发生了2次破坏性地震.在石门乡猴子岩(女姑村)一带,地震造成了滑坡、崩塌、地裂缝和断层等次生地质灾害现象.该处形成地震次生地质灾害比较严重的主要原因是:位于震中附近,受地震波影响大;多条断层和多组节理切割岩体,破碎的岩体在震动作用下易滑塌;岩层为软硬相间的结构,易形成发生滑坡和崩塌的地貌;陡崖和陡坡容易形成崩塌和滑坡.  相似文献   

4.
以贵州省赤水市立树天崩塌为例,基于野外地质灾害详细调查,总结崩塌的形成因素及失稳模式,通过FLAC3D软件建立软硬岩互层条件下的三维地质数值模型,以此分析崩塌的稳定性,结果表明:立树天崩塌的形成与斜坡岩性组合、危岩体结构面及气象条件有关,其失稳模式包括差异风化阶段、岩体破坏阶段与岩体失稳崩落阶段;泥岩空腔附近出现拉应力...  相似文献   

5.
以三峡库区某崩塌危岩体为例,通过工程地质分析方法对红层区近水平厚层~巨厚层状的软弱基座型斜坡崩塌破坏演化过程进行了研究.研究认为:受长江河谷侵蚀下切作用,斜坡原始地应力环境发生改变,发生垂直于河谷方向的卸荷回弹变形,逐步发展演化形成卸荷裂隙;受特殊的"上硬下软"岩性控制,下伏相对软弱岩层受上覆硬岩重力压致作用,产生不均匀压缩蠕变,向临空方向塑流挤出,致使上部硬岩产生倾倒变形,直至加剧卸荷裂隙扩展,甚至形成新的拉张裂隙,加剧了崩塌危岩体的发展演化,导致了崩塌的产生.结合灾害特征提出了以"固硬束软"、"上下兼顾"为原则的防治工程措施.  相似文献   

6.
通过对岷江上游茂县以北马脑顶—两河口段 1∶1万地质剖面的测制和 1∶2 .5万地质测绘 ,系统地揭示了该段滑坡和崩塌堆积的特征。在此基础上 ,分析了滑坡、崩塌形成的控制因素 ,认为岩性、构造、地震等为滑坡、崩塌形成的主要控制因素。最后对该河段内主要滑坡、崩塌堆积体的稳定性进行了初步评价  相似文献   

7.
西藏林芝6.9级地震崩塌地质灾害模式浅析   总被引:2,自引:2,他引:0  
2017年11月18日,西藏林芝米林县发生M_s6.9级地震,震源深度10 km。为了揭示林芝6.9级地震触发的地质灾害特征,通过现场野外实地调查和卫星遥感解译得出:林芝6.9级地震触发的地震地质灾害以小型崩塌为主,分为土质崩塌和岩质崩塌,土质崩塌模式主要有浅表层崩塌,堆积体中的块石、孤石等震动滚落崩塌;岩质崩塌模式有:拉裂-倾倒崩塌、震动-滑移崩塌、震动-坠落式崩塌;林芝地震触发的地质灾害主要受地形地貌,地层岩性组合,人类工程建设活动影响;具有明显的地形放大效应,崩塌源主要分布在山体斜坡的凸出部位和坡性转折部位以及单薄山脊等强卸荷部位。  相似文献   

8.
汶川地震诱发了大光包滑坡,其特征独特倍受关注.通过野外调查、勘探测试和室内试验等对该滑坡滑带的岩体碎裂特征进行分析,结合振动台模拟试验还原滑带岩体地震中裂化情形,对强震巨型滑坡滑带碎裂机制做了一定程度的理论分析和试验验证,得出滑带岩体损伤碎裂化是内因外因综合作用的结果,为地震荷载诱发岩体内部缺陷动态演化的累进过程.模拟试验效果较好,生动再现损伤过程,揭示地震致滑带岩体碎裂机制,相比单一的理论分析更为有效.  相似文献   

9.
针对古水水电站争岗堆积体目前处于稳定状态,在降雨、地震等不利条件下可能发生滑坡以至于威胁下游洞室群出口安全的问题,在地质勘查的基础上,选取典型剖面进行地质特性分析,并建立合理的颗粒离散元模型,进行不同工况量变条件下的滑坡复活数值模拟。结果表明:滑面倾角急剧增大和断层发育处容易产生裂隙,且影响着滑坡启滑位置;滑面平均作用3 m水头时堆积体出现蠕滑,5 m水头时三期滑坡复活;当地震强度达到0.3g时,一级平台堆积体开始滑动,形成三期滑坡。  相似文献   

10.
鹰嘴岩危岩区位于巴中市南江县县城边缘,在汶川“5.12”地震及其后的余震作用下,使岩体原有的节理、裂隙得到进一步的发展、贯通,从而使岩体形成了诸多不利的危岩体;在对巴中市南江县鹰嘴岩危岩的工程地质、地质环境详细研究和对危岩体典型特征及形成机制进行研究的基础上,论证鹰嘴岩危岩的形成与地震及危岩体附近的工程地质、地质环境等的相互关系。研究结果表明,危岩稳定性现状处于基本稳定至欠稳定状态,暴雨和地震条件下处于欠稳定至不稳定状态,其危险性大。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

16.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

19.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

20.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

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