共查询到17条相似文献,搜索用时 125 毫秒
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中国计量科学研究院于1983年开始设计研究中国第二代可移式激光绝对重力仪(NIM-Ⅱ型),1985年完成实验装置,并参加在法国巴黎举行的第二次国际绝对重力仪比对活动,1987年完成全部研究工作计划.本文较详细地阐述了近4年来在全国大面积实施绝对重力观测的结果.尤其在北京香山地震台,为了探索微重力观测研究,已建立了4个绝对重力点,开展了重力纵向垂直梯度、横向水平点位差及随时间变化的绝对重力观测研究.多年来为地震研究、地球物理研究及测绘、计量、国防等部门积累了一批绝对观测数据资料.这些基础性观测工作,对今后研究重力的非潮汐变化也有重要的意义. 相似文献
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中国计量科学研究院于1983年开始设计研究中国第二代可移式激光绝对重力仪(NIM-Ⅱ型),1985年完成实验装置,并参加在法国巴黎举行的第二次国际绝对重力仪比对活动,1987年完成全部研究工作计划.本文较详细地阐述了近4年来在全国大面积实施绝对重力观测的结果.尤其在北京香山地震台,为了探索微重力观测研究,已建立了4个绝对重力点,开展了重力纵向垂直梯度、横向水平点位差及随时间变化的绝对重力观测研究.多年来为地震研究、地球物理研究及测绘、计量、国防等部门积累了一批绝对观测数据资料.这些基础性观测工作,对今后研究重力的非潮汐变化也有重要的意义. 相似文献
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介绍了中国科学院测量与地球物理研究所的LCR-ET20重力仪和中国地震局地震研究所的DZW-9重力仪在三峡水库首区的重力固体潮比对观测.获得了该地区高精度的重力固体潮潮汐参数,估算了DZW-9重力仪的格值,其值为(-756.06plusmn;0.05)times;10-8(mbull;s-2)/v. 分析了相应仪器的重力观测残差, 数值结果表明DZW-9重力仪的长期漂移具有线性特征, 观测精度与LCR-ET20重力仪在同一量级. 本文提供的相关结果可为该地区地表和空间大地测量观测提供有效的重力潮汐改正模型. 相似文献
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1983年8月儿日至13日在西德汉堡举行了第十一届国际重力委员会(简称IGC),IGC会上集中总结、研究了世界各国的精密重力测量及各种重力仪的性能情况,会上布郎什(Boulanger)教授和国际计量局绝对重力仪的研究者佐久间博士全面介绍了各国绝对重力仪在国际计量局(简称BIPM)的比对结果及装置情况。从总结介绍的结果看,参加比对国家的仪器在BIPM比测结果是良好的,所测得的差值 相似文献
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1983年8月儿日至13日在西德汉堡举行了第十一届国际重力委员会(简称IGC),IGC会上集中总结、研究了世界各国的精密重力测量及各种重力仪的性能情况,会上布郎什(Boulanger)教授和国际计量局绝对重力仪的研究者佐久间博士全面介绍了各国绝对重力仪在国际计量局(简称BIPM)的比对结果及装置情况。从总结介绍的结果看,参加比对国家的仪器在BIPM比测结果是良好的,所测得的差值 相似文献
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重力基点网是我国开展地质调查、地震监测、测绘等测量工作的重要基础设施,面对原有基点网覆盖面不足且受到不同程度损害这一现状,目前已不能满足开展大比例尺重力调查以及高频率重复监测等工作的需求.本文以广西重力基点网重建为契机,利用A10-022绝对重力仪对全区42个重力基点与2个相对重力仪标定场的绝对重力值进行了测定.整个实施周期涵盖了计量参数校准、全球绝对重力仪国际比对、室内同点重复性以及全网部分基点独立安装检查等较为完整的测量流程,并通过连续运输与观测期间环境因素的记录与对比分析,总结了适合于该类型仪器室外条件下工作的技术手段与应对措施.观测结果表明:利用A10绝对重力仪能够高效率与高精度的完成广西重力基点网室外设计点位测定工作,国际比对及重复性验证确保了本次重建基点结果的可信度;A10采用双模式的氦氖激光频率存在漂移并受温度及气压等多种因素的综合影响,但短期内中心频率未出现较大波动,建议定期对其进行校准;各基点观测误差主要受到台站质量、人文活动及突发事件等环境扰动的影响,并与仪器内外温差存在较高的相关性.本文给出的A10绝对重力仪的参数设计、技术手段与影响因素的详细分析,能够为今后同类型仪器的观测实施提供重要参考,并有助于室外绝对重力观测的全国推广与应用.
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本文述评了各国绝对重力仪过去历次国际比对结果,并对今后国际大比对提出某些建议。 相似文献
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F. Greco G. Currenti G. D’Agostino A. Germak R. Napoli A. Pistorio C. Del Negro 《Bulletin of Volcanology》2012,74(7):1745-1756
To achieve a balance between uncertainty and efficiency in gravity measurements, we have investigated the applicability of combined measurements of absolute and relative gravity as a hybrid method for volcano monitoring. Between 2007 and 2009, three hybrid gravity surveys were conducted at Mt Etna volcano, in June 2007, July 2008, and July 2009. Absolute gravity data were collected with two absolute gravimeters, which represent the state of the art in recent advances in ballistic gravimeter technology: (1) the commercial instrument FG5#238 and (2) the prototype instrument IMGC-02. We carried out several field surveys and confirmed that both the absolute gravimeters can still achieve a 10 μGal or better uncertainty even when they are operated in severe environmental conditions. The use of absolute gravimeters in a field survey of the summit area of Mt Etna is unprecedented. The annual changes of the gravity measured over 2007–2008 and 2008–2009 provide unequivocal evidence that during the 2007–2009 period, two main phenomena of subsurface mass redistribution occurred in distinct sectors of the volcano, accompanying different eruptive episodes. From 2007 to 2008, a gravity change of ?60?μGal was concentrated around the North-East Rift. This coincided with a zone affected by strong extensional tectonics, and hence might have been related to the opening of new voids. Between 2008 and 2009, a North-South elongate feature with a maximum gravity change of +80?μGal was identified in the summit craters area. This is interpreted to indicate recharge of a deep-intermediate magma storage zone, which could have occurred when the 2008–2009 eruption was still ongoing. 相似文献
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《Journal of Geodynamics》2010,49(3-5):325-330
The network of superconducting gravimeters (SG) of the ‘Global Geodynamics Project’ (GGP) offers the unique opportunity to supplement and validate the gravity field variations derived from the GRACE satellite mission. Because of the different spatial and temporal resolutions of the gravity data a combination of all datasets can be used to retrieve a maximum of information regarding mass transfers especially related to hydrology which is deployable as constraint for hydrological modelling.For a consistent combination of the datasets the gap between terrestrial data of superconducting and absolute gravimeters (AG) and from satellite data has to be bridged. A successful combination of SG and AG data could be realized for several stations which resulted in time series of the highest accuracy and long-term stability.In principle, the same reductions applied to GRACE data have to be taken into account for the terrestrial data. The separation of local hydrological effects in SG observations is crucial for the comparison with satellite-derived gravity data. It is shown that even for stations with a hydrological challenging situation such as Moxa/Germany local hydrology-induced effects can be successfully modelled.Currently, the study focuses on Europe with its dense and long-term observation network. Regarding the consistency of the SG gravity variations they are representative for a larger region. From a comparison with GRACE-derived gravity field changes, and the variations due to hydrological models a principle good agreement emerges. 相似文献
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I. Marson 《Geophysical Prospecting》2012,60(2):361-372
We report here the results obtained during a feasibility study that was pursued in order to evaluate the performances of absolute airborne gravimetry. In contrast to relative systems, which use spring‐type gravimeters, each measurement acquired by absolute systems is independent from the others and the instrument is not suffering from problems like instrumental drift, frequency response of the spring and variation of the calibration factor. After a validation of the dynamic performance of the experimental setup in a moving truck, a comparison between the experimental airborne data retrieved over the Swiss Alps and those obtained by ground upward continuation at flight altitude allow us to state that airborne absolute gravimetry is feasible. The first test flight shows a spatial resolution comparable to those obtained by relative airborne gravimetry. For a wavelength on the order of 12 km the absolute value of gravity can be evaluated with an uncertainty of 6.9 mGal. 相似文献
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