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91.
琼东南盆地东部层间断层系及其形成机制分析 总被引:1,自引:1,他引:0
基于琼东南盆地最新3D地震资料的地质与地球物理解释,运用先进的地震剖面相干处理技术,在琼东南盆地东部早-中中新世泥岩中发现了大量层间断层,这些断层剖面上为板状正断层,倾角一般大于45°,长度不超过1000m,但是平面走向在不同区域差异很大。研究区层间断层为以体积收缩机制为主要形成机制,在区域应力、重力滑塌和超压水力破裂多种力学机制共同影响下形成的,基本限制在层间的、多种类型和多种性质的断层组合。研究区东北部主要为体积收缩机制形成的层间断层,并受到重力滑塌的影响,断层主要表现为平行于等深线的EW向的断层密集带和与之垂直的SN向直线状断层;中部主要受超压水力破裂作用和体积收缩机制的影响,断层主要由放射状断层和与之垂直的层间断层两部分组成;西南部地区主要受体积收缩作用和区域应力场的影响,在构造断层影响区,层间断层走向与构造断层相互垂直,未影响区则表现为断层多边形。 相似文献
92.
We treat the ocean carbon cycle as a coupled physical-biogeochemical process. The interactions between mixed-layer dynamics
and growth of phytoplankton in the layer are discussed, and the formal relationship between phytoplankton accumulation and
new production is examined. A coupled biological-physical model is presented for studying the classical spring bloom in the
N. Atlantic, and possible differences in the mechanisms that drive the seasonal phytoplankton blooms in the N. Atlantic and
the Arabian Sea are discussed. Finally, recommendations are made for observational programs to improve our understanding of
the biologically-mediated carbon cycle in the Arabian Sea. 相似文献
93.
Reduced visibilities have been simulated in the laboratory by means of a hydrosol. It was illuminated homogeneously by iodine quartz lamps producing an illuminance similar to a bright day. In the hydrosol several visibility targets were suspended at different distances and the visibility observation was performed by counting the number of visible objects. By this method a very accurate and fast determination of the visibility was possible. The extinction coefficient of the hydrosol was determined with a long path photometer: the intrinsic brightness of the objects in the illuminated hydrosol was determined for several wavelengths by means of a fiber optic. The correlation between the measured visibility and the extinction coefficient shows that the frequently used visual range underestimates the visibility, since the highest perception for an atmospheric aerosol is not at 550 nm but at 580 nm wavelength. Therefore it is suggested to use the atmospheric extinction coefficient at 580 nm for the calculation of the visual range. All colored objects could be seen less far, since they had a smaller contrast at the wavelength of maximum perception than the black object. Dark colored objects can be seen further than bright ones. Especially objects that have a high reflection in the yellow and organe have a small visibility. If the intrinsic brightness of the objects and the extinction coefficient (both as a function of wavelength) are known, the wavelength of maximum perception can be calculated and from this the visibility. The visibility thus calculated agrees with the observed visibility. If visibility observations in the atmosphere have to be performed with non-black objects, methods for corrections to the visibilty of a black object are given. 相似文献
94.
应用地块构造几何学方法和原理,系统研究了山西断陷带北部构造区地块构造类型、结构和运动特征. 运用断块多米诺模型,通过断裂构造地貌分析对比,系统地讨论了断块变形、断陷盆地伸展运动特点,及其区域分布特征. 分析结果显示:① 以北西向断裂划分,由西向东分为西区段、中区段和东区段,相应的地壳伸展量分别为4.46 km, 2.80 km和1.86 km.。断块平均伸展量约为1 km. 计算结果与实际测量数据大致相同; ② 以恒山断块为界,山西断陷带北部构造区可分为南北两区, 两区地震活动水平不同,分别为M7和6M 相似文献
95.
The objective is to provide, in one single paper, a complete collection of equations governing kinematic and dynamic ray tracing related to a symmetry plane of an anisotropic medium. Well known systems for kinematic ray tracing and in-plane dynamic ray tracing are reformulated for the purpose of clarity, by taking advantage of a vector representation of the Christoffel matrix elements and related quantities. A generalized formula is derived for the integrand in out-of-plane dynamic ray tracing, pertaining to a monoclinic medium. Integrands corresponding to non-tilted orthorhombic and transversely isotropic media are obtained as special cases. 相似文献
96.
于慎谔 《地震学报(英文版)》2004,17(4):417-425
Introduction Shanxi fault depression zone (SFDZ) is one of important Cenozoic fault basin zones and strong earthquake belts in Chinese mainland. Its northern part has aroused wide research interests due to the complicated tectonics and high activity of strong earthquakes there. Early researches on this depression zone were carried out since 60s of last century (DENG, et al, 1973; DENG, YOU, 1985; LU, DING, 1985; XU, 1990; XU, et al, 1996, 2002). In 90s of last century, the geologica… 相似文献
97.
98.
Common-ray tracing and dynamic ray tracing for S waves in a smooth elastic anisotropic medium 总被引:1,自引:0,他引:1
L. Klimeš 《Studia Geophysica et Geodaetica》2006,50(3):449-461
Anisotropic common S-wave rays are traced using the averaged Hamiltonian of both S-wave polarizations. They represent very
practical reference rays for calculating S waves by means of the coupling ray theory. They eliminate problems with anisotropic-ray-theory
ray tracing through some S-wave slowness-surface singularities and also considerably simplify the numerical algorithm of the
coupling ray theory for S waves.
The equations required for anisotropic-common-ray tracing for S waves in a smooth elastic anisotropic medium, and for corresponding
dynamic ray tracing in Cartesian or ray-centred coordinates, are presented. The equations, for the most part generally known,
are summarized in a form which represents a complete algorithm suitable for coding and numerical applications. 相似文献
99.
分析了连续位图图像几何交换的理论基础,并在此基础上时地图拼幅,点阵字符的无级处理等方面做了一些尝试。所提出的仿射变换方法,较好地满足了连续图像几何交换的精度,保持了拓扑不变性,并保证了无级交换时时原图的高度仿真。此外,还给出了利用此方法进行实验的部分结果。 相似文献
100.
Fiona A. Harrison Finn E. Christensen William Craig Charles Hailey Wayne Baumgartner C. M. H. Chen James Chonko W. Rick Cook Jason Koglin Kristin-Kruse Madsen Michael Pivavoroff Steven Boggs David Smith 《Experimental Astronomy》2005,20(1-3):131-137
Hard X-ray/soft gamma-ray astrophysics is on the verge of a major advance with the practical realization of technologies capable of efficiently focusing X-rays above 10 keV. Hard X-ray focusing telescopes can achieve orders of magnitude improvements in sensitivity compared to the instruments based on coded apertures and collimated detectors that have traditionally been employed in this energy band. Compact focal planes enable high-performance detectors with good spectral resolution to be employed in efficient, low-background configurations. We have developed multilayer coated grazing incidence optics and solid state Cadmium Zinc Telluride focal plane systems for the High Energy Focusing Telescope (HEFT) balloon-borne experiment, and for the Nuclear Spectroscopic Telescope Array (NuSTAR) Small Explorer satellite. In this paper we describe the technologies, telescope designs, and performance of both experiments. 相似文献