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691.
提出了一种适用于地震计远程监控功能接口的实现方式,扩充了地震数据采集器的应用。  相似文献   
692.
We have made a data collection and analysis system for recording microcracks in rock to study the three dimensional pattern of fracture and the dynamic properties of rock during pressurization. This system, with 8 channel data detection, records in real-time, from the initial microcracks to the final vibration waveform excited by the master fracture. The detected data are recorded digitally at the hard disk of an IBM computer (or 286, 386 personal computer) as well as transmitted to disk. The sampling rate for each channel is 10 MHz. Collecting every acoustic emission events in the loaded rock sample with 8 channels by this system, mathematically modelling the AE event travel time, and taking the coordinates of the AE event hypocenter and the three components of P wave velocity as unknown parameters, we set up a set of residual equations for joint inversion, so that the three dimensional localization of AE event hypocenters can be completed under variable velocities, which will lay foundations for the research on rock fracture clearly. The Chinese version of this paper appeared in the Chinese edition ofActa Seismological Sinica,13, 489–495, 1991. The design and development of the system, and the experiments are sponsored by the Chinese Joint Seismological Science Foundation.  相似文献   
693.
    
A new multidimensional scaling (MS) technique, referred to as the Pijk model, is formulated on the basis of associations among triple objects (samples or variables), instead of pairs of objects as used in the usual MS methods, such as factor analysis. The computational scheme provided for this method is the reduction of an original problem to a standard eigenvalue-eigenvector problem. The major goal of the technique is simplification and reduction of data structures and the rescaling of original objects into a new and reduced space, so that patterns and relations of the original objects can be conventiently examined in two-dimensional factor plots. The Pïjk method is illustrated and tested by using a set of geochemical data related to the epithermal gold and silver vein deposits in the Walker Lake quadrangle of Nevada and California. The characteristics of element associations suggested in the Pijk analysis are consistent with field observations. A preliminary comparison between the new method and the ordinary factor analysis also is made on the basis of the same data set. Results are encouraging in that analysis by the Pijk model captures triple-object associations that might be missed by the ordinary factor analysis which considers only pair-variable correlations  相似文献   
694.
695.
塔里木盆地古城低凸起三维地震工区内的奥陶系碳酸盐岩埋藏深,非均质性强,且无钻井资料。重点对奥陶系鹰山组三段—四段白云岩的串珠状地震反射体进行地质诠释。采用均方根振幅属性预测了储层平面分布规律,应用缝洞雕刻技术预测了裂缝和串珠体发育区,运用相干、曲率属性预测了断裂、裂缝的分布,联合应用频率衰减梯度、低频能量、平均频率和吸收系数等手段进行了油气检测。通过对多种信息的综合分析,评价优选出有利勘探目标。基于上述工作部署的A井,在鹰山组三段灰质白云岩储层中获天然气勘探重大突破,证实了地震综合预测方法的有效性。  相似文献   
696.
Data refinement refers to the processes by which a dataset’s resolution, in particular, the spatial one, is refined, and is thus synonymous to spatial downscaling. Spatial resolution indicates measurement scale and can be seen as an index for regular data support. As a type of change of scale, data refinement is useful for many scenarios where spatial scales of existing data, desired analyses, or specific applications need to be made commensurate and refined. As spatial data are related to certain data support, they can be conceived of as support-specific realizations of random fields, suggesting that multivariate geostatistics should be explored for refining datasets from their coarser-resolution versions to the finer-resolution ones. In this paper, geostatistical methods for downscaling are described, and were implemented using GTOPO30 data and sampled Shuttle Radar Topography Mission data at a site in northwest China, with the latter’s majority grid cells used as surrogate reference data. It was found that proper structural modeling is important for achieving increased accuracy in data refinement; here, structural modeling can be done through proper decomposition of elevation fields into trends and residuals and thereafter. It was confirmed that effects of semantic differences on data refinement can be reduced through properly estimating and incorporating biases in local means.  相似文献   
697.
中国大陆深探测的大地电磁测深研究   总被引:8,自引:1,他引:8  
通过对地震波速度、密度、磁性、导电性等物理场进行观测,研究地壳与上地幔的物性与结构特征,将为研究地球内部物质状态、地壳运动过程及其动力学机制等科学命题提供科学依据,同时也将为寻找深部大型矿床提供信息。大地电磁深探测方法作为研究地球壳幔电性结构的主要地球物理方法,在国内外完成了大量探测工作,取得了许多重要的研究成果。在研究壳幔构造方面,大地电磁法和地震方法一起被视为两大支柱方法,在世界范围内解决大陆动力学问题方面已有许多成功的应用范例。但由于大地电磁探测以天然电磁场作为场源,在矿集区等强干扰地区往往很难采集到高信噪比的数据,抗干扰能力较弱。同时,大地电磁与地震数据的约束反演以及联合解释目前尚没有达到实用化,这些都限制了大地电磁数据的处理及解释精度。深部探测技术与实验研究(SinoProbe)专项下属的深部探测技术实验与集成项目将选择青藏高原、西部造山带与华南山区结晶岩等复杂地质条件和不同人文干扰水平地区,以大地电磁探测与地震探测作为主要手段,研究深部精细地球物理探测技术的集成,并且通过实验剖面研究这些实验区的壳幔结构特征。其中的大地电磁测深大剖面观测实验与壳/幔三维电性研究课题,将通过在实验区的大地电磁观测实验,研究适用于不同地质条件及干扰水平地区的大地电磁数据采集方法技术以及精细处理与反演方法,同时探讨大地电磁数据与地震数据的约束反演以及联合解释。该研究将提高深部地球物理探测精度,为深部精细地球物理探测方法技术集成以及区域地球物理精细探测提供范例。已经完成的青藏高原东北缘西秦岭造山带和福建结晶岩地区的大地电磁观测试验表明,在这些典型地质构造区域,虽然存在施工困难,干扰水平大等各种不利因素,但只要采取合适的野外观测技术,并通过数据精细处理与反演计算,是能够获得高质量的大地电磁数据以及可靠的电阻率分布模型。试验所取得的成果,将为实现深部探测技术实验与集成项目科学目标和研究任务提供重要的技术支撑与保障。  相似文献   
698.
699.
通过对2008年格尔木地震台2套仪器记录的磁场变化进行对比分析,分别从GM3仪器三分量(磁偏角D、地磁场水平强度H、垂直强度Z)与FHDZ—M15三分量(D、H、Z)记录的全年整点值、日均值及月均值进行对比分析,阐述了其运行特点,找到2套仪器的一致性与差异性。  相似文献   
700.
We describe a method for the extraction of spectra from high-dispersion objective prism plates. Our method is a catalogue-driven plate solution approach, making use of the right ascension and declination coordinates for the target objects. In contrast to existing methods of photographic plate reduction, we digitize the entire plate and extract spectra off-line. This approach has the advantages that it can be applied to CCD objective prism images and spectra can be re-extracted (or additional spectra extracted) without having to re-scan the plate. After a brief initial interactive period, the subsequent reduction procedure is completely automatic, resulting in fully reduced, wavelength-justified spectra. We also discuss a method of removing stellar continua using a combination of non-linear filtering algorithms.   The method described is used to extract over 12 000 spectra from a set of 92 objective prism plates. These spectra are used in an associated project to develop automated spectral classifiers based on neural networks.  相似文献   
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