期刊文献+
共找到3篇文章
< 1 >
每页显示 20 50 100
环太平洋俯冲带内双地震带及其成因机制研究进展 被引量:17
1
作者 张克亮 魏东平 《地球物理学进展》 CSCD 北大核心 2008年第1期31-39,共9页
俯冲带作为地球最为庞大的循环系统的重要组成部分,已成为地球科学的研究热点之一.很多俯冲带,特别是环太平洋俯冲带内的中深源地震,在空间上呈明显的分层分布,并且各层地震具有不同的震源机制,即所谓的双地震带现象.本文简要介绍了环... 俯冲带作为地球最为庞大的循环系统的重要组成部分,已成为地球科学的研究热点之一.很多俯冲带,特别是环太平洋俯冲带内的中深源地震,在空间上呈明显的分层分布,并且各层地震具有不同的震源机制,即所谓的双地震带现象.本文简要介绍了环太平洋双地震带形态特征与震源机制的空间分布,并回顾了双地震带的几种成因模型.根据形态特征和震源机制的差异,中源深度的双地震带可以分为两类,其中,一类双地震带对应上、下二层分别为压缩和张性的地震分布;另一类双地震带的震源分布较浅,且其浅部地震以横向压缩为主.此外,日本本州东北俯冲带的地震分布可能是由三层地震带组成的,而且汤加、伊豆-小笠原地区还发现深源深度的双地震带.通过对双地震带的形态特征以及其热力学条件的研究,人们从抗弯作用、脱水脆化、相变断层等多方面,尝试建立解释双地震带成因的模型.目前,大多数研究利用数值计算结果,结合蛇纹石脱水脆化、相变断层模型,能够不同程度地分别解释中源和深源双地震带成因.不过,这些模型几乎相互独立,并不能同时解释中源和深源双地震带.有人试图尝试用统一模型解释中深源地震成因,例如,先前存在的断层模型,不过该模型还不很具有说服力.也可能是多种因素的联合作用,共同影响着俯冲板内的温度场、应力场分布. 展开更多
关键词 俯冲带 双地震带 抗弯作用 脱水脆化 相变断层
下载PDF
Bilateral Macular Lesions Following Electrical Injury
2
作者 Chan Wu Rong-ping Dai +2 位作者 Fang-tian Dong Hong Du Hua Zhang 《Chinese Medical Sciences Journal》 CAS CSCD 2016年第3期196-199,共4页
HIGH-VOLTAGE electrical injuries can result in a variety of ocular complications. Cataract and macular edema are the most common injuries.Other injuries include punctate keratopathy,uveitis,macular hole,subretinal mac... HIGH-VOLTAGE electrical injuries can result in a variety of ocular complications. Cataract and macular edema are the most common injuries.Other injuries include punctate keratopathy,uveitis,macular hole,subretinal macular haemorrhage,and choroidal atrophy.We report a case that optical coherence tomography (OCT) and multifocal electro- retinogram (mfERG) clearly demonstrated the bilateral macular lesions following electrical injury, while the fundus examination was nearly normal. 展开更多
关键词 electrical injury macular lesion optical coherence tomography multifocal electroretinogram
下载PDF
Properties of an improved Gabor wavelet transform and its applications to seismic signal processing and interpretation
3
作者 Ji Zhan-Huai Yan Sheng-Gang 《Applied Geophysics》 SCIE CSCD 2017年第4期529-542,621,共15页
This paper presents an analytical study of the complete transform of improved Gabor wavelets (IGWs), and discusses its application to the processing and interpretation of seismic signals. The complete Gabor wavelet ... This paper presents an analytical study of the complete transform of improved Gabor wavelets (IGWs), and discusses its application to the processing and interpretation of seismic signals. The complete Gabor wavelet transform has the following properties. First, unlike the conventional transform, the improved Gabor wavelet transform (IGWT) maps time domain signals to the time-frequency domain instead of the time-scale domain. Second, the IGW's dominant frequency is fixed, so the transform can perform signal frequency division, where the dominant frequency components of the extracted sub-band signal carry essentially the same information as the corresponding components of the original signal, and the sub- band signal bandwidth can be regulated effectively by the transform's resolution factor. Third, a time-frequency filter consisting of an IGWT and its inverse transform can accurately locate target areas in the time-frequency field and perform filtering in a given time-frequency range. The complete IGW transform's properties are investigated using simulation experiments and test cases, showing positive results for seismic signal processing and interpretation, such as enhancing seismic signal resolution, permitting signal frequency division, and allowing small faults to be identified. 展开更多
关键词 Seismic signal inverse transform Gabor wavelet transform FAULTS RESOLUTIONS instantaneous phase
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部