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991.
基于仙女山-九畹溪断裂带附近地区地质构造,讨论三峡水库蓄水前后该断裂带附近地区的地震活动特征,同时分析该区域2014-03 M4.5与M4.7地震间的触发关系及2次地震对后续小震的影响。结果表明:1)M4.7地震可能由M4.5地震与库水渗流产生的较大孔隙压力共同触发。2)M4.5与M4.7两次地震的应力扰动导致研究区内地震活动增加,后续地震中约66.9%的地震发生于库仑应力增强区。3)2次地震产生的静态库仑应力变化导致仙女山断裂带附近地区地震活动增加,后续地震活动水平将处于背景地震活动水平之上;九畹溪断裂带活动性相对较弱,略小于背景地震活动水平,且处于应力积累阶段。 相似文献
992.
993.
?????????????????????????????????????ó???????????????????????仯??????1???????????仯????????????????NNW-SSE??????????3~9 kPa a-1???????????仯???????????????NEE-SWW??????????1~6 kPa a-1?????????????????????????????????????£?2???????????仯????????????????NNW????????????????,??????????????????????????????????仯???????????????NEE????????λ?????????????????????仯????????????????????????????????????????????п????????Щ???????????????????3?????????????????????????????????з???????????-???ε???????????????????6 kPa a-1?????-?????ε???????????????????5 kPa a-1???????κ??????媲????ε????????????????????3~4 kPa a-1?? 相似文献
994.
995.
We briefly review recent developments in black hole accretion disk theory, emphasizing the vital role played by magnetohydrodynamic
(MHD) stresses in transporting angular momentum. The apparent universality of accretion-related outflow phenomena is a strong
indicator that large-scale MHD torques facilitate vertical transport of angular momentum. This leads to an enhanced overall
rate of angular momentum transport and allows accretion of matter to proceed at an interesting rate. Furthermore, we argue
that when vertical transport is important, the radial structure of the accretion disk is modified at small radii and this
affects the disk emission spectrum. We present a simple model demonstrating how energetic, magnetically-driven outflows modify
the emergent disk emission spectrum with respect to that predicted by standard accretion disk theory. A comparison of the
predicted spectra against observations of quasar spectral energy distributions suggests that mass accretion rates inferred
using the standard disk model may be severely underestimated. 相似文献
996.
997.
998.
Pedro Augusto Alastair C. Edge Claire J. Chandler 《Monthly notices of the Royal Astronomical Society》2006,367(1):366-374
We present multifrequency, multi-epoch radio imaging of the complex radio source B2151+174 in the core of the cluster, Abell 2390 ( z ≃ 0.23) . From new and literature data, we conclude that the Faranoff–Riley type II (FRII)-powerful radio source is the combination of a compact, core-dominated 'medium-sized symmetric object' (MSO) with a more extended, steeper spectrum mini-halo. B2151+174 is unusual in a number of important aspects. (i) It is one of the most compact and flat spectrum sources in a cluster core known; (ii) it shows a complex, compact twin-jet structure in a north–south orientation; (iii) the orientation of the jets is 45° misaligned with apparent structure (ionization cones and dust disc) of the host galaxy on larger scales. Since the twin-jet of the MSO has its northern half with an apparent 'twist', it might be that precession of the central supermassive black hole explains this misalignment. B2151+174 may be an example of the early stage (103 –104 yr duration) of a 'bubble' being blown into the intracluster medium where the plasma has yet to expand. 相似文献
999.
Jiang-He Yang Jun-Hui Fan Department of Physics Electronics Science Hunan University of Arts Science Changde Center for Astrophysics Guangzhou University Guangzhou National Astronomical Observatories Chinese Academy of Sciences Beijing Physics Institute Hunan Normal University Changsha 《中国天文和天体物理学报》2005,5(3):229-237
We collect 119 v-ray-loud blazars (97 flat spectrum radio quasars (FSRQs) and 22 BL Lacertae objects (BL Lacs)), and investigate possible correlations between their γ-ray emission (maximum, minimum and average values) at 1 GeV and the radio emission at 8.4 GHz. Our main results are as follows. For the lower state γ-ray data, there is no correlation between the γ-ray and radio flux density; For the high state γ-ray data, there are good correlations for the whole 119 blazars and 97 FSRQs, and a weak correlation for the 22 BL Lac objects; For the average γ-ray data, there are good correlations. According to our analysis, we propose that the γ-rays are associated with the radio emission from the jet, and that the γ-ray emission is likely from the SSC process in this case. 相似文献
1000.