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1.
《四川地震》1996,(1):1-2
经过对宝鸡-彭县、天水-宝轮地区进行详细的实地调查,对重点地段开展了槽探和剥土,采集年代样及构造岩薄片样,实测可流阶地位相剖面,同时还搜集了遥感图象解译等资料和区前人所作工作成果。  相似文献   

2.
G-856数据的采集和回放软件的应用张振国(中国北京I00039国家地震局综合观测中心)将G-856质子旋进磁力仪用于我国地震地磁观测或进行其他物探测量已多年,但基本上停留在人工观测和人工记录的工作状态下。本文提出和解决了G-856在自动测量中所存储...  相似文献   

3.
皖东张八岭,珠龙地区西冷岩组微古植物群初步研究   总被引:1,自引:0,他引:1  
皖东张八岭、珠龙地区西冷岩组为一套浅海相变质火山-沉积岩系,岩性以细碧-石英角斑岩为特征,出露面积约占总面积的80%,视厚度为4616.51m。笔者等在1:5万区域地质填图中对这套变质岩系进行了生物地层工作,并采集了大量的微古植物样品,从中获得了丰富的微古植物化石。按化石组合特征将其分为两个组合:第一组合主要产于拂晓园艺场-朱郢剖面冷岩组下部层位,包括有33个属44个种,其中1个新属,2个新种,1  相似文献   

4.
在野外考察和测量以及断层活动年代品的采集和测定的基础上,通过室内的综合分析研究,查明了黄山-米山断裂的空间分布,鉴定了断裂的活动时代和运动性质,评价了断裂对米山水库稳定性的影响。研究结果表明,黄山-米山断裂呈南北向展布,分北、中、南三段;以挤压逆冲运动为主,兼有左旋走滑运动。黄山-米山断裂带物质固化较结程度较高,地形地貌上无断层显示,没有断错Q2以来的地层(本区缺失Q1地层),对历史地震和现代地震不具控制作用,系非第四纪活动断裂;对米山水库库区和坝区的稳定性影响较小。  相似文献   

5.
赵国敏  徐中信 《中国地震》1994,10(4):378-387
本文介绍了STM-PC微机系列上实现的地震测控资料现场收录系统,其中包括对模拟磁带地震记录进行A/D转换、数据采集等,在研究中,对时标信号的采集方式、六响报时信号处理、模拟回放电路的改进与采集速率等方面进行了试验,为高质量地进行A/D转换取得了经验。本文是以海城震区的实际资料为基础,对A/D转换的精度与效果进行了统计与分析,结果表明,该收录系统对模拟地震记录的A/D转换精度达到了规范要求。该收录系  相似文献   

6.
GZZ-1型自振柱试验机研制与性能试验   总被引:23,自引:3,他引:23  
作者研制成功GZZ-1型自振柱试验机,该机和动三轴试验机共用一套控制、采集及气压系统,并把纵向共振和自振柱集成为一套系统。实现了计算机自动控制及数据处理程序化。性能试验表明,该试验机动态响应好,运行可靠,操作方便,具有较高的试验精度。  相似文献   

7.
本文介绍了STM-PC微机系列上实现的地震测深资料现场收录系统,其中包括对模拟磁带地震记录进行A/D转换、数据采集等。在研究中,对时标信号的采集方式、六响报时信号处理、模拟回放电路的改进与采集速率等方面进行了试验,为高质量地进行A/D转换取得了经验。本文是以海城震区的实际资料为基础,对A/D转换的精度与效果进行了统计与分析,结果表明,该收录系统对模拟地震记录的A/D转换精度达到了规范要求。该收录系统与一般微机系列兼容,适用于我国目前使用的几种模拟磁带地震记录仪。  相似文献   

8.
附录B压缩算法1Steiml数据压缩原理台站安装的数字化地震数据采集系统输出的原始数据样本为二进制补码,4字节32位有符号整数时间序列。设一个数据记录的原始样本序列为X_0……X_n据差值公式 D_n=X_n-X_(n-1)可得第一差值序列D0=x0...  相似文献   

9.
将G-856质子磁经力仪用于流动地震地磁观测多年,但 停留在人工观测和人工记录的工作状态,本文提出和解决了用笔记本计算机采集、整理G-856观测数据的问题。在我们的工作的实践中表明,该方法快捷、准确,实现了成果整理计算微机化。  相似文献   

10.
介绍了SS-YD型断层观测伸缩仪的系统组成及其基本原理,。该系统实行现场自动采集和自动储存并由“数据交换器”进行数据调用和回放,具备交直流电源自动转换及有效的避雷装置,实现了无人值守。仪器所得观测数据稳定,并记录到清晰的应变固体潮汐与台湾“9.21”大地震0.5μm的同震阶跃。  相似文献   

11.
基于脉冲检测的混合震源数据分离   总被引:1,自引:0,他引:1       下载免费PDF全文
混合震源采集技术相对于传统地震数据采集具有改善成像质量、提高采集效率的优势.减小混合炮中单炮之间的随机延时范围能够有效的提高采集效率,但这也给之后的混采数据分离带来了影响.混采数据经伪分离后非共炮域数据中的混叠噪声明显更加集中,不利于对混叠噪声进行压制.本文提出基于脉冲检测方法对混采数据进行分离,并且与迭代的多级中值滤波方法作对比,时间延时范围较大时,两种方法都能得到很好的分离结果;时间延时范围较小时,本文方法能更有效的去除混叠噪声,同时也能更好的保留细节信息.实际数据计算结果表明,本文方法一定程度上还能够有效压制其他随机噪声.  相似文献   

12.
海底大地电磁信号采集电路的驱动程序   总被引:9,自引:5,他引:4  
针对海底MT采集的特点,设计非实时智能监控驱动程序.程序可读入GPS时间,使海底大地电磁仪主控单元PC104的RTC时钟与GPS时钟在微秒级内保持一致,并能控制采集的同步启动,保证远参考测量的实现;通过读入人为设定的参数文件,实现预期的采集方式;利用数存前的级联分样剔除冗余信息;借助数据先驻留高端内存的方式降低写盘噪声。  相似文献   

13.
For data acquired with conventional acquisition techniques, surface multiples are usually considered as noise events that obscure the primaries. However, in this paper we demonstrate that for the situation of blended acquisition, meaning that different sources are shooting in a time‐overlapping fashion, multiples can be used to ‘deblend’ the seismic measurements. We utilize the recently introduced estimation of primaries by sparse inversion (EPSI) methodology, in which the primary impulse responses are considered to be the unknowns in a large‐scale inversion process. With some modifications the estimation of primaries by sparse inversion method can be used for blended seismic data. As output this process gives unblended primary impulse responses with point sources and receivers at the surface, which can be used directly in traditional imaging schemes. It turns out that extra information is needed to improve on the deblending of events that do not have much associated multiple energy in the data, such as steep events at large offsets. We demonstrate that this information can be brought in during acquisition and during processing. The methodology is illustrated on 2D synthetic data.  相似文献   

14.
海水面的虚反射(鬼波)引起海上拖缆采集数据陷波,导致地震记录频带变窄,而近年发展的变深度缆采集技术,具有多样的陷波特征,通过专门的去虚反射处理方法可获得宽频数据.本文基于已有研究成果,将最小二乘反演迭代压制虚反射算法应用于某海上变深度缆宽频处理.基于频率波数域镜像记录生成方法获得镜像炮集记录,并采用最小二乘解从变深度缆原始和镜像炮集记录中提取上行波.针对镜像炮集记录生成受初始速度模型精度的影响,使得某深度缆接收的上行波和下行波之间的实际延迟时间存在误差,采用最小二乘反演迭代算法最优化计算下行波与上行波之间的平均延迟时间和上行波记录,并采用时空数据窗口滑动克服延迟时间随炮检距和目的层深度变化问题.合成数据及某海上实际变深度缆数据处理测试结果表明,该方法能较好地压制变深度缆由海水面产生的虚反射,能达到拓宽地震记录频带目的.  相似文献   

15.
浅层地震勘探数据拟同步采集时差分析与实践   总被引:2,自引:1,他引:1       下载免费PDF全文
理想的地震勘探数据采集,其硬件系统采用多道同步方式实现,保证多路信号的时间或相位一致性.理论时差分析表明,就地震信号的初至时刻来看,多路同步采集系统也存在系统误差.浅层地震勘探数据记录道数少,采用单个A/D模数转换器件通过逻辑系统控制实现少量地震道的多路循环分时采集,在满足采样定理所需采样频率和不增加地震信号初至系统误差的前提下,可以以较少的硬件成本实现浅层地震信号的有效采集,这种采集方式我们称之为有效拟同步采集;通过实践证明了其采集方式的有效性.  相似文献   

16.
Simultaneous sources acquisition, also referred to as “blended acquisition”, involves recording two or more shots simultaneously. It allows for denser spatial sampling and can greatly speed up the field data acquisition. Thus, it has potential advantage to improve seismic data quality and reduce acquisition cost. In order to achieve the goal of blended acquisition, a deblending procedure is necessary. It attenuates the interference and thus improves the resolution of the pre-stack time migration image. In this paper, we propose an efficient deblending method, which applies frequency-varying median and mean filters to cross-spread azimuth-offset gathers (XSPR-AO). The method can be used with variable window sizes according to the characteristics of the interference. The effectiveness of the method is validated by a field data example.  相似文献   

17.
The effects of source and receiver motion on seismic data are considered using extensions of the standard convolutional model. In particular, receiver motion introduces a time-variant spatial shift into data, while source motion converts the effect of the source signature from a single-channel convolution in time to a multichannel convolution in time and space. These results are consistent with classical Doppler theory and suggest that Doppler shifting can introduce distortions into seismic data even at relatively slow acquisition speeds. It is shown that, while both source and receiver motion are known to be important for marine vibroseis acquisition, receiver motion alone can produce significant artifacts in marine 3D data. Fortunately, the convolutional nature of the distortions renders them amenable to correction using simple deconvolution techniques. Specifically, the effects of receiver motion can be neutralized by applying an appropriate reverse time-variant spatial shift, while those due to source motion can be addressed by introducing time-variant spatial shifts both before and after standard, deterministic, signature deconvolution or correlation.  相似文献   

18.
In the simulation experiments of earthquakes in laboratory, the instability slip or rupture events are obtained through steady state loading to simulate earthquake processes. In the experiments, steady-state deformation and unstable sliding occur alternately. It is hard to determine the origin time and duration of the instability event of fault, and there may be many instability events in one experiment. Therefore, in order to ensure that sufficient data is obtained at the extremely short instability moment to analyze the mechanical process of the earthquake source, the data acquisition system is required to continuously collect data at high-speed from the beginning of the experiment until the end, and the lasting time can be more than ten hours, so it requires huge storage space. Although the upper frequency limit of the instability signal is unknown exactly, but the previous experiments have shown that the frequency of the signal will reach hundred to several kilohertz, so the sampling frequency of the data acquisition should be above megahertz. In this case of long-time continuous high-frequency data acquisition, it is still necessary to maintain a high signal-to-noise ratio. Furthermore, previous studies have proved that the source mechanics field has a complex spatial structure, which is difficult to describe with a few measuring points, and it is necessary to perform simultaneous measurements of the source mechanics field for dozens or more measuring points. The combination of long-term continuous recording, high-resolution high-frequency sampling and multi-point simultaneous measurement poses a huge challenge to the technical indicators of the observing system. With the method for composing distributed synchronous acquisition machine group by using multiple high-resolution high-frequency sampling computers, a super dynamic deformation measurement system of high signal-to-noise ratio, which features 64-channel, 16-bit resolution, 4MHz sampling frequency, and parallel continuous acquisition with tens of hours was developed. This system can realize the synchronous acquisition of various signals, such as strain, acoustic emission, electromagnetic waves and displacement, so it is convenient for analyzing the conversion relationship between various physical quantities.  相似文献   

19.
High Fidelity Vibratory Seismic (HFVS) acquisition and separation can play an important role in today's land acquisition schemes. The method – in which multiple vibrators are swept simultaneously using sweeps with known phase encoding and then the data are inverted and separated into individual records – can improve productivity in the field and at the same time improve signal characteristics in the data. It relies on the measured weighted sum of accelerations (base plate and reaction mass) to invert the acquired data and separate the individual vibrator responses. Separation can be sub-optimal if the measured motions vary from the 'true source' input into the ground. Differences in true source and measured source can arise due to poor coupling between vibrators and ground, soil compaction or other factors. Using both a synthetic model and real data, we show that if the true source changes between sweeps but is not measured, vibrator responses can leak into adjacent vibrator responses upon separation. In a recent survey with HFVS acquisition, we observed a 25–30 dB separation between adjacent vibrators, which could be improved with greater reliability of the source measurement. The vibrator leakage can reduce the data quality considerably. We discuss the results of this survey and show that separation is affected by source measurement error. Further, we conclude that it is necessary either 1) to use source measurements that can capture the variability of the true source between sweeps or 2) to compensate for the source measurement variations in processing or in acquisition.  相似文献   

20.
The rough sea surface causes perturbations in the seismic data that can be significant for time‐lapse studies. The perturbations arise because the reflection response of the non‐flat sea perturbs the seismic wavelet. In order to remove these perturbations from the received seismic data, special deconvolution methods can be used, but these methods require, as input, the time varying wave elevation above each hydrophone in the streamer. In addition, the vertical displacement of the streamer itself must also be known at the position of each hydrophone and at all times. This information is not available in conventional seismic acquisition. However, it can be obtained from the hydrophone measurements provided that the hydrophones are recorded individually (not grouped), that the recording bandwidth is extended down to 0.05 Hz and that data are recorded without gaps between the shot records. The sea surface elevation, and also the wave‐induced vertical displacement of the streamer, can be determined from the time‐varying pressure that the sea waves cause in the hydrophone measurements. When this was done experimentally, using a single sensor seismic streamer without a conventional low cut filter, the wave induced pressure variations were easily detected. The inversion of these experimental data gives results for the sea surface elevation that are consistent with the weather and sea state at the time of acquisition. A high tension approximation allows a simplified solution of the equations that does not demand a knowledge of the streamer tension. However, best results at the tail end of the streamer are obtained using the general equation.  相似文献   

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