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91.
黄骅坳陷横向变换带的构造特征及成因 总被引:33,自引:10,他引:33
讨论了黄骅坳陷横向变换带的构造特征和成因。根据利用地震反射剖面对盆地构造几何学的研究,圈定了不同尺度的横向变换带,确定了伸展构造背景下的横向变换带是为了保持区域伸展应变调节构造变形的一种调节体系。这种伸展应变守恒是靠三维空间上断层位移沿走向的变化实现的。横向变换带的构造样式为横向地垒状凸起和鼻状凸起或鼻状背斜,并具伸展性质的正断层。横向凸起与非叠复的和叠复的分段断层系伴生及发育在断层位移最小处等事实表明,横向凸起或横向鼻状背斜是由于分段断层系位移沿走向变化形成的。 相似文献
92.
Recent attention given to the concept of vertical integration and disintegration of production processes has identified the existence of a continuum, with small, flexibly specialized producers at one end and large, mass production units at the other end. Firms along the continuum constantly strive for the optimum combination of economies of scale and scope. This paper attempts to identify the organizational characteristics of high technology firms in one industrial complex of the U.S. Manufacturing Belt. A principal components analysis is performed on a number of theoretically relevant variables for a sample of high technology establishments in Northeast Ohio. The results indicate that the region contains a variety of organizational forms ranging from isolated workshops to large, vertically integrated assembly plants. These findings conform to expectations derived from recent conceptualizations in the literature. Additional empirical research will further enhance understanding of the processes that shape the organization of production in territorial complexes. 相似文献
93.
高围压下冻结砂土的强度特性 总被引:2,自引:6,他引:2
在高围压条件下,对冻结兰州砂土在不同温度和不同应变速度下进行三轴压缩试验,试验结果表明,围压的增大和应变速度的减小明显增强了冻土的塑性性能;同时,随围压的增大,冻土的抗剪强度增加,但随围压的进一步增加,它出现降低的趋势,存在一个临界 围压,此临界围压值随温度的变化而变化,但不随应变速率而变化。 相似文献
94.
95.
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
96.
97.
本文通过对广丰县周家坞中奥陶统露头剖面层序、体系域、副层序的研究,识别出了三个不同性质的Ⅱ型层序界面和二个三级层序,确认这三个层序界面为符合实际又易于野外识别的自然界面,并对SQ2中反映最大海泛期的高分辨异旋回驱动机制事件,提出可能受米兰柯维奇频率的春分点和秋分点间约2万年间隔的控制。 相似文献
98.
杨文强 《物探化探计算技术》1997,19(3):270-273,278
为研究高密度电阻率法对各种三维地电体的反映规律,本文介绍了正演程序编制的方法并给出了计算实例。 相似文献
99.
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
100.
Bi Fuzhi Yuan Youshen Institute of Crustal Dynamics State Seismological Bureau Beijing 《《地质学报》英文版》1997,71(4):395-406
This paper expounds the quantitative tectonic indicators and some qualitative indicators of large earthquakes in the coast areas of Fujian, Guangdong, Taiwan and Hainan. The main quantitative indicators include uplift amplitude of the Moho, Quaternary and Late Holocene coasts. The paper also gives a brief account of the research method on quantitative indicators of surface uplifted zones. Taiwan is a famous neotectonic zone and an area of large earthquakes in the world. There is only one large-earthquake area in each of Fujian, Guangdong and Hainan Provinces. Along the coast large earthquake areas there are certainly many remains of crustal activity. Among these remains, coast activity, taking the sea level as the accurate marker horizon, can determine not only the amplitude of coastal elevation and subsidence in a certain period, but also the cycle and rate of positive or negative movements. 相似文献