排序方式: 共有58条查询结果,搜索用时 281 毫秒
1.
Basil Tikoff Matthew R. Davis Christian Teyssier Michel de St. Blanquat Guillaume Habert Sven Morgan 《Tectonophysics》2005,400(1-4):209-226
The Cascade Lake shear zone occurs on the eastern margin of the Tuolumne Intrusive Suite, Sierra Nevada Batholith, California. Foliation in the zone is NNW trending and subvertical, and lineation is moderately south plunging. Deformation is syn-tectonic with emplacement of the Cathedral Peak granodiorite. A deformation gradient exists toward the NE margin of this pluton, with higher strains and lower temperatures of deformation found near the contact. We compare fabric data collected very densely in this shear zone using several techniques: field fabrics, 3D orientation of K-feldspar megacrysts, and AMS (anisotropy of magnetic susceptibility) analysis. In general, the results from the three different methods are in agreement. Deformation in this shear zone is part of a larger pattern of deformation within the Cathedral Peak granodiorite, as recorded by AMS analysis, and dextral shearing associated within the last stage of plutonism within the Sierra Nevada magmatic arc. 相似文献
2.
辽南金州拆离断层带中花岗质岩石的变形:显微构造、组构与年代学分析 总被引:1,自引:0,他引:1
花岗岩(脉)在中下地壳韧性剪切带中普遍发育,如何正确鉴别剪切带中剪切前、剪切期及剪切后花岗岩(脉)以及正确理解剪切过程中构造变形与岩浆作用之间的关系一直是一个重要课题。本文以辽南金州拆离断层带为研究对象,选取中部地壳伸展作用过程中具有不同变形表现的花岗岩(脉)开展宏观-微观构造观察、石英EBSD组构分析及锆石LA-ICP-MS年代学测试等工作,从而进一步丰富构造-岩浆关系判别准则。剪切前花岗岩(脉)多变形强烈且具有后期固态变形叠加在早期高温岩浆组构之上的特点,而剪切期的花岗岩由于侵位的时间不同,岩石的变形程度也会不同。剪切晚期侵入的岩脉遭受了较弱的晶内塑性变形,而剪切早期的岩脉可以显示岩浆流动或结晶后高温至中温固态变形。从组构特点上看,剪切前和剪切期花岗质岩石石英c轴组构大多表现为中高温组构叠加有低温组构的特点。剪切后的花岗质岩石仅发生微弱的晶内变形或未变形而显示低温或无规律的组构特征。对五个典型的样品进行年代学测试,其结果符合相应的期次划分类型。应用宏观构造、显微构造与组构分析,结合年代学测试综合分析,对于辽南变质核杂岩构造-岩浆活动性进行了精细划分,包括134~130Ma初始伸展阶段,130~115Ma峰期伸展与强烈岩浆活动阶段,以及115Ma前后伸展作用结束。 相似文献
3.
介绍滇中红层形成的地质历史背景,红层分布范围,主要地层岩性及区内地质构造。重点讨论滇中红层特别是红层软岩的岩体原生结构,及后期受构造改造的岩体结构特性,岩体风化特性,岩体水理作用特性,岩体物理力学性质等四方面的工程地质特性。 相似文献
4.
H. Hellmann 《洁净——土壤、空气、水》1996,24(5):218-225
IR Spectroscopy and Further Analyses of New Fabric Rinse Agents Distearyldimethylammoniumchloride (DSDMAC) that dominated the fabric softener market in Germany in the past is now substituted by three new types of ester-based agents, i.e. imidazoline ester, ester quats, and diester quats what poses new challenges to surface water analytics. The IR spectra and the chromatographic behaviour of these three agents are more or less similar to those of naturally occuring fatty esters. The paper reports about the use of IR spectroscopy, its benefit in the sense of fingerprinting principle, the identification of substances by functional groups, and the analytical tracing of transformation products. The latter relates to the formation of salts with anions that are easily detectable, the clean up, and the final spectroscopic determination. While in 1994 DSDMAC was still determinable in concentrations of 10…20 mg/kg in suspended solids from the Middle Rhine River, the concentration of the substitutes was below the detection limit of 2 mg/kg and 1…2 μg/L in 1995. 相似文献
5.
In this paper, the swelling–shrinkage properties of the compacted expansive soil in the Huaiyin Section of the Ning-Lian Highway are introduced, and swelling–shrinkage mechanisms are discussed based on changes in soil water content, dry density, material composition and fabric. The improvement of the compacted expansive soil by lime is also discussed briefly. It is concluded that careful attention should be paid to this type of compacted expansive soil. 相似文献
6.
In order to describe the anisotropic failure of soils caused by the internal fabric, isotropic failure criterion should be generalized to be anisotropic. This paper achieves the generalization by introducing a simple method, called anisotropic transformed stress method, which apparently differs from the common way. Physical interpretation of this method are analyzed further. Using this method, many existing isotropic criteria can become anisotropic in the same way, and will be expressed by a unified formula finally. To verify this method, anisotropic Unified Strength Criterion is used to predict the peak strength of anisotropic soils in different loading conditions. 相似文献
7.
We test the hypothesis that small ductile shear zones are developed from initial rheologically weak domains. We regard weak domains as ellipsoidal inhomogeneities and apply Eshelby's formalism extended for power-law viscous materials to investigate the kinematics and finite strain evolution of the partitioned flow fields in weak domains. We show that, under an imposed bulk flow field, weak domains, regardless of their initial shapes and orientations, deform into zone-like features at relatively small bulk strains and the deformation paths inside weak domains have all characteristics expected in ductile shear zones. We apply our model to the Cap de Creus area Spain, where abundant small ductile shear zones exist. To relate the fabrics inside these shear zones with the regional deformation, we take a multi-scale approach. We assume that the area contained many weak domains which were randomly shaped and oriented initially and were deformed into shear zones eventually in response to the regional flow. We constrain the regional flow field by the fabric patterns across the area and compute numerically the partitioned flow fields in individual weak domains. The latter are related to fabrics inside shear zones. Our model reproduces first-order features of field-observed fabrics. Although the deformation path of each shear zone was close to simple shearing, the deformation of the whole belt was not. Our approach also resolves the strain compatibility problem for a finite-sized shear zone embedded in a far less deformed country rock. 相似文献
8.
针对传统协同开发系统普遍采用"中心化"存储架构带来的单点故障、数据不可信、故障难以追责等安全问题,以及传统协同办公系统仅支持单一企业内部办公的问题,本文借助超级账本Fabric区块链技术以及业务流程管理和服务组合技术实现了一款基于Fabric区块链的智能合约协同开发系统.系统架构中首先结合传统中心化存储技术和区块链去中心化存储技术,通过将系统核心业务数据信息存储在区块链分布式账本中而把业务流程管理等不重要的数据存储在传统数据库中解决了"中心化"存储管理带来的安全信任问题.其次系统通过结合超级账本联盟链技术提供的企业联盟的特点使得系统可以应用于企业联盟办公中,解决了单一办公的问题. 相似文献
9.
东江水库诱发地震的地震地质背景研究 总被引:7,自引:0,他引:7
从区域地质、断裂活动性、构造岩溶等研究入手,应用多种断层活动年龄测定分析、岩组分析、显微构造和小构造分析、构造岩溶和应力场综合分析,提出,东江水库诱发地震与库区主要断裂带的活动性无直接联系,而是受岩溶地层分布和多种构造复合引起的复杂薄弱带的制约。当水库蓄水,水位上升,导致渗水,孔隙压力增大,致使薄弱带内部由于小规模破裂或薄弱面的重新滑动而进行的应力调整引起诱发地震。随着水库蓄水的稳定,内部应力逐渐调整趋于平衡,水库诱发地震活动性将逐渐趋于平静 相似文献
10.
It has been known for many years that depositional method plays an important part in the results of laboratory testing of clean sands. In this paper, undrained triaxial compression tests were performed on specimens composed of Nevada sand with 20% non-plastic silt content using a variety of depositional methods that include slurry deposition, water sedimentation, air pluviation, mixed dry deposition, and dry funnel deposition. It was found that there was a marked difference in the undrained behavior even though the density and stress conditions were identical. The conclusion was that the soil fabric was responsible for this result. Using the scanning electron microscope, a method was developed to examine and quantify the microstructure of silty sand. These results appear to indicate that there are internal particle structures in sand with silt and their relative quantities correlate with the observed macroscopic undrained behavior. 相似文献