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排序方式: 共有92条查询结果,搜索用时 15 毫秒
61.
TheBeijingnetworkofdigitalgeomagneticpulsationobservatoriesJun-ChengZHOU(周军成);Ke-LiHAN(韩克礼);YueLU(鲁跃)(InstituteofGeophysics,S...  相似文献   
62.
南海及邻域新构造运动基本特征   总被引:6,自引:1,他引:6  
本文根据南海及邻域的岩石圈动力学环境,把新构造类型划分为离散型、聚敛型、平移型和滑动型。依据构造不整合、地层缺失、断裂、变形、变质及火山活动等构造事件,提出本区新构造始于晚渐新世的新认识,详细分析了本区新构造运动的脉动性及造陆、造山、造海、造盆等性质,并对其构造演化与动力学模型进行初步的探讨。  相似文献   
63.
A new material migration hypothesis for the plate subduction zone orogeny, so-called ‘the cordilleran-type orogeny’, is proposed on the basis of geological constraints as well as mechanics of accretionary wedges. The major tectonic processes of the hypothesis comprise: (i) episodic, extensive magmatism along the margin of an overriding plate; (ii) supply of voluminous igneous and eroded materials through forearc to trench, with an increase in the net sediment influx into trench; (iii) accelerated accretion of sediments beneath an overriding older accretionary wedge; and (iv) upward material migration within the wedge and resultant exhumation of high-P/T metamorphic rocks near the inland margin of the wedge. This hypothesis was validated by the test using available geo- and thermo-chronological data from two classical types of subduction-related orogens in Southwest Japan and California. The hypothesis, coupled with the thermochronologic point of view, requires the reconsideration of coevality of paired metamorphism. The temporal pairing is to be observed between the beginning of the regional high-T/P metamorphism and that of the uplift and exhumation of high-P/T metamorphism, with some time lag needed for material migration. Where the temporal pairing is examined therefore, the formation age of igneous rocks and related high-T/P metamorphic rocks should be compared to the exhumation age of high-P/T metamorphic rocks. The episodic, extensive magmatism that triggers the cordilleran-type orogeny shows a temporal correlation in the mid-Cretaceous for most circum-Pacific continental margins. The resultant widespread formation of accretionary complexes is also observed in the western part of the circum-Pacific margins. The deduced mid-Cretaceous circum-Pacific orogeny accompanied a gross increase in the continental crust production rate, and was approximately coeval with the Pangea breakup and the Central Pacific superplume episode, implying the orogeny as a part of the mid-Cretaceous pulsation of the Earth.  相似文献   
64.
Using d'Alembert equation as the approximation of Einstein's equation, a solution is given in this paper to the time-dependent gravitational equation of the Earth in consideration of the Earth's features, which describes the characteristics of pulsation of the Earth and the structures of spherical layers of its interior, thus providing a theoretical basis for establishing the idea of mantle pulsation.  相似文献   
65.
造父变星周光(PL)关系对于宇宙距离尺度研究和哈勃常数测定具有重要意义,所涉及的内容颇为广泛,可包括两类不同星族造父变星的PL关系,PL关系的绝对定标,周光色(PLC)关系,PL关系的金属度效应,多波段PL关系,极大光度PL关系和多相PL关系,以及非线性形式的PL关系,等等。  相似文献   
66.
Asteroseismology studies stars with a wide variety of interior and surface conditions. For two decades asteroseismic techniques have been applied to many pulsating stars across the HR diagram. Asteroseismology is now a booming field of research with stunning new discoveries; I highlight a personal selection of these in this review, many of which are discussed in more detail elsewhere in these proceedings. For many years the Nainital-Cape Survey for northern roAp stars has been running at ARIES, so I emphasise new spectroscopic results for roAp stars and point out the outstanding prospects for the planned ARIES 3-m telescope at Devastai. High precision spectroscopy has revolutionised the asteroseismic study of some types of stars — particularly solar-like oscillators and roAp stars — while photometry is still the best way to study the frequency spectra that are the basic data of asteroseismology. New telescopes, new photometers and space missions are revolutionising asteroseismic photometry. In addition to the ground-based potential of asteroseismic spectroscopy, India has the knowledge and capability for space-based asteroseismic photometry. The future for asteroseismology is bright indeed, especially for Indian astronomers.  相似文献   
67.
Pi2地磁脉动的理论进展   总被引:1,自引:1,他引:1  
目前,国内外在Pi2脉动的理论研究上取得了很大进展,现在问题的焦点是如何完整地解释Pi2脉动的全球特征和激发机制。解释Pi2脉动的理论主要有三种,即瞬态响应机制,亚暴电流楔理论和磁层空腔振荡理论。本文介绍了这三种理论的由来和发展,分析了每种理论在Pi2脉动研究中的贡献,并对Pi2脉动理论研究的进一步发展提出一些看法。  相似文献   
68.
南极中山站Pc3地磁脉动特征   总被引:2,自引:2,他引:2       下载免费PDF全文
根据1992年2月9日军1993年2月9日南极中山站地磁脉动观测资料,选出Pc3脉动事件进行分析研究,重点研究南极中山站Pc3脉动的出现频次、频率特性和振幅特性,并对南极中山站记录的Pc3脉动的激发和传播机制进行理论研究.  相似文献   
69.
杨武  白志刚  余海涛  马暄  臧颖  陈成  戴磊 《海洋工程》2016,34(5):101-108
海洋波浪能可再生能源的开发是未来发展的趋势,开发设计更为高效的波能转换利用装置是开发利用波浪能的关键。根据脉搏脉动机理,设计发明了一种柔性胶囊发电装置,利用柔性结构的强收缩性,让其随着波峰波谷收缩扩张,进而形成脉动来传输水体,使相连尾端竖管内水位随着脉动骤升骤降来压缩排出和快速吸入空气。进行了一系列探索性实验,着重研究柔性材料厚度、波高、周期、气室孔径对该试验装置的波能转换率的影响,数据表明,柔性硅胶管有很好的聚波作用,气室的设计和建造对波能转换效率有较大的影响。  相似文献   
70.
ȷ������ư�װ��λ������Է�����   总被引:3,自引:0,他引:3  
??????????????????????????????????????????Χ??????????????????????????????????????????????????????????ο????????????????????????????????????????????????????????????λ?????????????????????????  相似文献   
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