韧性剪切带的变形变质与同构造熔融作用——以中祁连地块宝库河韧性走滑剪切带为例   总被引：5，自引：0，他引：5  

戚学祥  李海兵  张建新  蔡金郎 《地质论评》2003,49(4):413-421

宝库河韧性剪切带是发育在中祁连地块北缘上的一条向北陡倾,走向近东西,宽约6 km的右行平移型韧性剪切带.剪切带内岩石原岩为泥质岩、基性岩和花岗岩,变质程度达角闪岩相,变形变质温度在685～763±46℃之间,压力在0.62～0.83±0.13 GPa范围内.其内长英质条带非常发育,规模变化较大,分布局部相对集中且受剪切带控制,走向与剪切带一致,平行于叶理,孤立无根,并在后期递进变形过程中发生不同程度的糜棱岩化、布丁化和褶皱,主要成分为长石和石英,明显不同于韧性剪切前或后侵入的花岗岩脉或岩体.长英质条带特征、REE配分模式及剪切带内岩石的变形变质温度说明剪切带内发育的长英质条带与基体是同源的,是在剪切应变过程中剪切热使围岩内部分物质发生动态熔融形成的,是同构造熔融作用的产物.  相似文献   

地图投影的最小二乘二元多项式拟合的误差估计     

张晓盼  齐欢 《测绘科学》2003,28(3):49-51

探讨了在地图投影的最小二乘二元多项式拟合中参考点的分布对拟合误差的影响,提出了一种基于矩阵的秩亏的方法来判断参考点是否在指定次数的二元多项式空间的代数曲线上,并导出在极小范数最小二乘意义下的拟合多项式的误差估计式,公式表明拟合误差和参考点的最小二乘误差无关。  相似文献   

黑土的水土流失及其保育治理   总被引：10，自引：2，他引：10  

王其存  齐晓宁  王洋  刘兆永  鲍强 《地理科学》2003,23(3):361-365

黑土因其肥沃而闻名，但其退化和水土流失问题往往易被忽略。虽然在人类影响下的现代环境过程开始较晚，但黑土区的环境已发生了较大的变化。对黑土水土流失的现状进行了评价，指出了黑土保育治理的必要性与紧迫性，提出了治理保育措施。  相似文献   

Technology and Its Application： MIS with Geographical Information     

ChenWenming QiHuan 《中国地质大学学报(英文版)》2003,14(1):90-94

Despite the constant expansion of the application of GIS, in recent years, the data process-ing ability of the application system developed with GIS_Tool is quite limited. Management information system with the geographical information can not only be used to deal with data commonly, but also deal with digitized maps as GIS_Tool does. Thus it can help the user develop an application system high-qual-ified both in maps and traditional data. This paper, by taking the method of integrated MapInfo in the application of Visual Basic as an example, mainly illustrates two technological problenm-integrated map technology and the multiuserization of Maplnfo geographical information. And also the concrete solu-tions to the problems are provided.  相似文献   

Synthesis of accelerations of the 1976 Tangshan earthquake(M_S 7.8)in near-and far-field by using semi-empirical method     

罗奇峰  胡聿贤 《地震学报(英文版)》1997,(3)

Ｓｙｎｔｈｅｓｉｓｏｆａｃｃｅｌｅｒａｔｉｏｎｓｏｆｔｈｅ１９７６Ｔａｎｇｓｈａｎｅａｒｔｈｑｕａｋｅ（ＭＳ７．８）ｉｎｎｅａｒａｎｄｆａｒｆｉｅｌｄｂｙｕｓｉｎｇｓｅｍｉｅｍｐｉｒｉｃａｌｍｅｔｈｏｄＱＩＦＥＮＧＬＵＯ１）（罗奇峰）ＹＵ?..  相似文献   

流体成矿系统与成矿作用研究   总被引：24，自引：4，他引：24  

贾跃明 《地学前缘》1996,3(4):253-258

对几乎所有金属矿床类型来说，其形成过程均与金属从源岩的活化、原始渗滤、矿质运移和金属沉淀富集成矿关系密切，这些过程主要是由流体的运动和作用完成的。因此，识别金属和流体的来源，追溯流体从源区将金属运载至最终成矿部位所经过的路径，以及查明金属和流体沿运移通道发生的物理、化学和时间上的各种变化及其特殊性质，可以为矿床评价与勘查提供很有价值的定量成矿信息。成矿流体的来源－运移－沉淀（－堆积）过程会以流体成矿系统的形式保留下来。对流体成矿系统和作用的全面了解可通过调查活动的和古代的两种系统获得。活动流体成矿系统是目前正在进行原始矿质搬运的系统，调查这些系统可对运移通道中的含矿流体进行取样和监测研究。古流体成矿系统包括各时代从含金石英脉到铅－锌矿脉系统的所有热液脉型矿床以及沉积喷气型和所谓层控矿床。对含矿矿物和岩石的广泛岩石学、化学、流体包裹体和同位素研究将为定量评价与预测矿床的分布和变化提供至关重要的资料。流体成矿系统内具有一些重要特征，如各种地质要素的方向性、相关性和指示性变化。  相似文献   

High Pressure-Differential Thermal Analysis and Ultrasonic Wave Amplitude Analysis of Ice-Water Equilibrium at 1.5-5.0GPa     

Xu Yousheng  Zheng Haifei  Xie Hongsen  Zhang Yueming  Xu Huigang  Guo Jie 《中国地球化学学报》1996,15(2):153-158

Water is the most active component in all geological systems.It has an important effect on the physical properties of minerals and melts.It also plays a key role in the evolution of the Earth.Accurate thermodynamics data on water are currently confined to pressures below 1.0GPa and temperatures below 900℃.Presented in this paper are new data available on the P-T properties of water at pressures up to 5.0GPa,develoged from differential thermal analysis and ultrasonic wave amplitude analysis.It has been found that there may exist another ternary point at 3.0GPa and that ultrasonic wave amplitude change of ice-water transition shows two inflection points above 2.0GPa, consistent with the two peaks of differential thermal curves above 2.0GPa .It may be a new phenomenon which needs further study.  相似文献   

0.25—3.75GPa和20—370℃条件下0.025molNaCl溶液电导率研究          下载免费PDF全文

郑海飞  谢鸿森 《地质学报》1997,71(3):274-280

在０．２５－３．７５ＧＰａ和２０－３７０℃条件下测量了ＮａＣｌ溶液的电导率。结果表明（１）电导率随温度增高而增大，且电导率的对数与温度的倒数为线性关系，但不同压力不其斜率不同。（２）电导率与压力的 关系较为复杂，存在着不连续性。即在２．２５－３．３７ＧＰａ压力范围，电导率随压力增大而增大；在１．２５－２．００ＧＰａ压力范围，电导率与压力几乎无关；０．７５ＧＰａ压力的电导率高于相邻力的电导率。上述。  相似文献   

Conductivity of NaCl solution at 0.4–5.0 GPa and 25–500 °C     

Yousheng Xu  Hongsen Xie  Jie Guo  Haifei Zheng  Yueming Zhang  Maoshuang Song 《中国科学D辑(英文版)》1997,40(4):398-402

NaCI-H₂O is the most fundamental ternary system in geology. Until now, the measurements of electrical conductivity of NaCl solutions are still little at high pressures (> O.5 GPa) We measured the conductivity of 0.01 m NaCl solution at 0.4–5.0 GPa and 25-500°C. The results are consistent with that of Quist and Marshall (1968) at 0.4 GPa. The conductivity of NaCl solution increases with increasing temperature. The results also show that the conductivity of NaCl solution changes little with increasing pressure below 1.5 GPa and changes rapidly with increasing pressure above 1.5 GPa. The rapid increase of the conductivity of NaCl solution may play an important role in many geological processes (such as the genesis of ore deposits under hydrothermal condition) and other fields. Project supported by the National Natural Science Foundation of China.  相似文献   

Properties of wave velocity for two types of granitoids at high pressure and temperature and their geological meaning   总被引：1，自引：0，他引：1  

Shufeng Yang  Hanlin Chen  Jishuang Jiang  Guoqiang Zhu  Hongshen Xie  Wei Hou  Yueming Zhang  Huigang Xu 《中国科学D辑(英文版)》1997,40(5):470-476

The wave velocity for two types of granitoids was measured using the analytic method of full-wave vibration at high pressure and high temperature. The laws of velocity changes for them differ with the pressure boost and temperature rise, and the velocity change of S-type is more violent than that of I-type. The “softening point” of compressional wave velocity (V μ) is also revealed during the measurement for two types of granitoids imitating the pressure and temperature at a certain depth. But the depth of “softening”, V_p after “softening” and the percentage of V_p’s drop around the “sofrening point” for two types of granitoids are obviously different. The depth of “softening” is 15 km approximately and V_p after “softening” is 5.62 km/s for S-type granitoid. But for I-type granitoid the depth of “softening” is 26 km approximately and V_p after “softening” is 6. 08 km/s. Through careful analysis of rock slices after the experiment, it was found that the “softening” of elastic-wave velocity is caused by the partial melting of granite. Combined with the results of geophysical prospecting, these results suggest that the low-velocity layers developing in the interior of Earth crust are related to thc partial melting of different types of granitoids. The formation of the low-velocity layer in the upper-middle Earth crust is closely related to the development of S-type granitoid, but that in the lower Earth crust is closely related to the development of I-type granitoid.  相似文献