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51.
本文探讨了利用地震矩反演断裂形变带运动学参数的基本理论和方法,将其初步应用于鲜水河断裂形变带变形分析和运动机制的研究。结果表明,鲜水河断裂带呈现出走向拉伸、倾向压缩的形变格局,由地震矩反演的断裂带剪切形变速率(10.9mm/a)与用地质学估算方法(17mm/a)和现今地壳形变测量(8mm/a)的结果相当。同时,反演出的应变主方向能解释鲜水河断裂现今活动分段性特征以及多种滑动方式共存的现状,从而证明该方法是目前研究区域运动学问题切实有效的手段之一。 相似文献
52.
1 INTRODUCTION Active oxygen free radicals can damage cell structure, even kill the cells, causing aging and cer- tain serious diseases (Bors et al., 1989). Usually, the production and scavenging of active oxygen free radicals are in balance in healthy hu… 相似文献
53.
In this paper, the equilibrium configurations of rapid rotating compact stars and some gravitational effects are studied within the general relativity by use of the Harrison-Wheeler equation of state and by the self-consistent field method. Numerical calculations show that the equilibrium configuration of a rotating star is a spheroid. For large spin velocities, say, ω > 3.0 × 102 sec−1 the eccentricity and mass increase very rapidly as the angular velocity increases, for the critical angular velocity of the rotating star, the eccentricity is about 0.7, the increase in mass is about 10–35%. The difference of the gravitational redshifts at the surface of the star caused by rotation, and the difference of the light bending when the beam moves in the direction of rotation or in the opposite direction are obvious. 相似文献
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56.
Yi-Sui Sun 《Celestial Mechanics and Dynamical Astronomy》1983,30(1):7-19
In this paper, using two methods: LCN'S (Lyapunov characteristic numbers) method and slice cutting method, we study numerically two mappings with odd dimension: $$T_1 :\left\{ {\begin{array}{*{20}c} {x_{n + 1} = x_n + z_n ,} \\ {y_{n + 1} = y_n + x_{n + 1} , (\bmod 2\pi )} \\ {z_{n + 1} = z_n + A\sin y_{n + 1} ,} \\ \end{array} } \right. T_2 :\left\{ {\begin{array}{*{20}c} {x_{n + 1} = x_n + y_n + B \sin z_n ,} \\ {y_{n + 1} = y_n + A \sin x_{n + 1} , (\bmod 2\pi ),} \\ {z_{n + 1} = z_n + B \sin y_{n + 1} ,} \\ \end{array} } \right.$$ whereA, B are parameters. For the mappingT 1 the whole region is stochastic; however, we find two-dimensional invariant manifolds for the mappingT 2. 相似文献
57.
鱼卡煤田大煤沟组高分辨率层序地层特征及聚煤规律 总被引:1,自引:0,他引:1
利用高分辨率层序地层学理论和技术方法,综合地震、测井、岩芯和煤质资料对柴达木盆地北缘鱼卡煤田中下侏罗统大煤沟组地层河湖三角洲沉积体系进行高分辨率层序地层学分析,从中识别出短期、中期、长期3个级别的基准面旋回层序,划分出向上"变深"非对称型、向上"变浅"非对称型及对称型3种短期基准面旋回基本结构类型。依据等时地层对比法则进行不同级次基准面旋回层序的联井对比,建立了大煤沟组的等时地层格架,在等时地层格架内进行了煤层对比,并在等时地层格架内分析了聚煤规律。 相似文献
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Chang-Guk Sun Sung-Ho Chun Tae-Gyun Ha Choong-Ki Chung Dong-Soo Kim 《Computers and Geotechnics》2008,35(3):436-449
An integrated GIS-based tool (GTIS) was constructed to estimate site effects related to the earthquake hazards in the Gyeongju area of Korea. To build the GTIS for the study area, intensive site investigations and geotechnical data collections were performed and a walk-over site survey was additionally carried out to acquire surface geo-knowledge data in accordance with the procedure developed to build the GTIS. For practical applications of the GTIS used to estimate the site effects associated with the amplification of ground motion, seismic microzoning maps of the characteristic site period and the mean shear wave velocity to a depth of 30 m were created and presented as a regional synthetic strategy addressing earthquake-induced hazards. Additionally, based on one-dimensional site response analyses, various seismic microzoning maps for short- and mid-period amplification potentials were created for the study area. Case studies of seismic microzonations in the Gyeongju area verified the usefulness of the GTIS for predicting seismic hazards in the region. 相似文献
60.
Min Sun Chao Yuan Wenjiao Xiao Xiaoping Long Xiaoping Xia Guochun Zhao Shoufa Lin Fuyuan Wu A. Kröner 《Chemical Geology》2008,247(3-4):352-383
Gneissic rocks in the Chinese Altai Mountains have been interpreted as either Paleozoic metasedimentary rocks or Precambrian basement. This study reports geochemical and geochronological data for banded paragneisses and associated gneissic granitoids collected along a NE–SW traverse in the northwestern Chinese Altai. Petrological and geochemical data suggest that the protoliths of the banded gneisses were possibly immature sediments with significant volcanic input and that the gneissic granitoids were derived from I-type granites formed in a subduction environment. Three types of morphological features can be recognized in zircons from the banded gneisses and are interpreted to correlate with different sources. Zircons from five samples of banded paragneiss cluster predominantly between 466 and 528 Ma, some give Neoproterozoic ages, and a few yield discordant Paleoproterozoic to Archean ages. Zircon Hf isotopic compositions indicate that both juvenile/mantle and crust materials were involved in the generation of the source rocks from which these zircons were derived. In contrast, zircons occur ubiquitously as elongated euhedral prismatic crystals in the four samples of the gneissic granitoids, and define single populations for each sample with mean ages between 380 and 453 Ma. The general absence of Precambrian inheritance and positive zircon ?Hf values for these granitoids suggest insignificant crustal contribution to the generation of the precursor magmas. Our data can be interpreted in terms of a progressive accretionary history in early to middle Palaeozoic times, and the Chinese Altai may possibly represent a magmatic arc built on a continental margin dominated by Neoproterozoic rocks. 相似文献