浙江省地震台网台站地动噪声分析     

刘洋君  沈晓健  陈吉锋  张明 《地震地磁观测与研究》2012,33(3):247-251

介绍浙江省数字地震台网基本情况,阐述功率谱分析的计算方法,并对各台站地动噪声计算分析。结果表明,各台站的台址环境和观测仪器的性能基本优良,能够适应宽频带地震观测要求。部分台址观测条件由于受到人为因素的影响,可以有针对性地对部分台站进行环境改造,为地震监测预报创造条件。  相似文献   

槽波地震勘探在煤矿大型工作面的应用   总被引：1，自引：0，他引：1  

任亚平 《煤田地质与勘探》2015,43(3):102

以陕北某煤矿大型工作面槽波地震工程为例,开展了超大型工作面内断层的槽波地震探测技术研究。槽波探测采用全排列接收,最大限度地保障了槽波信息的获得。根据得到的槽波记录数据以及CT成像结果,解释了工作面内断层的发育情况,与后期巷道揭露情况基本吻合。槽波地震勘探在大型工作面的成功应用,可为矿井实现盘区勘探提供技术支持。   相似文献   

Checking the quality of restoration in the frequency domain of CDSN broad-band seismograms using modern control engineering     

Hongji Li 《地震学报(英文版)》1992,5(3):597-607

Incorrect results including false low frequency components may appear during the recovery of ground motion in the frequency domain. In order to check the quality of restoration in the frequency domain of CDSN broad-band seismograms, a digital model of the seismograph systems, based on modern control engineering, is presented and improvement of the method of restoration in the frequency domain is described. Examples shown in this paper demonstrate the effectiveness of the proposed approach in improving the restoration of true ground motion. The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica,14, 90–99, 1992. The work is supported by the Chinese Joint Seismological Science Foundation.  相似文献   

Physical model for the downhole orbital vibrator (DOV) – II. Rotary correlation wavelets and time-lapse seismics     

P. C. Leary  L. A. Walter 《Geophysical Journal International》2005,163(2):663-688

  相似文献   

Seismic investigation of a bottom simulating reflector and quantification of gas hydrate in the Black Sea   总被引：1，自引：0，他引：1  

M. Zillmer  E. R. Flueh  J. Petersen 《Geophysical Journal International》2005,161(3):662-678

  相似文献   

Dynamic Ocean-Tide Effects On Earth's Rotation   总被引：1，自引：0，他引：1  

S. R. Dickman 《Geophysical Journal International》1993,112(3):448-470

  相似文献   

Determination of porosity and saturation using seismic waveform inversion     

H. Keers  L. Johnson  D. Vasco 《Studia Geophysica et Geodaetica》2007,51(1):119-140

Characterization of a reservoir model requires determination of its petrophysical parameters, such as porosity and saturation. We propose a new method to determine these parameters directly from seismic data. The method consists of the computation and inversion of seismic waveforms. A high frequency method is presented to model wave propagation through an attenuative and dispersive poroelastic medium. The high frequency approximation makes it possible to efficiently compute sensitivity functions. This enables the inversion of seismic waveforms for porosity and saturation. The waveform inversion algorithm is applied to two laboratory crosswell datasets of a water saturated sand. The starting models were obtained using travel time tomography. The first dataset is inverted for porosity. The misfit reduction for this dataset is approximately 50%. The second dataset was obtained after injection of a nonaqueous-phase liquid (NAPL), possibly with some air, which made the medium more heterogeneous. This dataset was inverted for NAPL and air saturation using the porosity model obtained from the first inversion. The misfit reduction of the second experiment was 70%. Regions of high NAPL and high air saturation were found at the same location. These areas correlate well with the position of one of the injection points as well as regions of higher NAPL concentrations found after excavation of the sand. It is therefore possible to directly invert waveforms for pore fluid saturation by taking into account the attenuation and dispersion caused by the poroelasticity.  相似文献   

华南大陆东部壳幔结构的宽频带地震学探测     

张永谦  石玉涛  张洪双  徐峣  江国明  韩如冰  严加永  张大魏 《地球学报》2022,43(6):755-770

华南大陆是新元古代以来全球地质演化历史最复杂的地区之一, 也是欧亚板块东南缘地壳生长和大陆增生最活跃, 大规模构造变形、岩浆活动和多金属矿产资源最丰富的地区。揭示该区浅表构造与岩浆活动和成矿作用机制离不开对深部壳幔结构的研究。宽频带地震学是开展深部壳幔结构探测的重要手段, 基于宽频带地震学数据可以刻画地壳-岩石圈-上地幔-地幔过渡带不同深度和尺度的深部结构, 为深入理解研究区的深部构造、动力学过程、岩浆活动与成矿作用提供有效约束。本文较全面地总结了近二十年来在华南大陆东部地区开展的宽频带流动地震探测工作, 并对研究区的地壳厚度、Vp/Vs比值、岩石圈底界(LAB)深度、上地幔速度结构与各向异性等进行了分析与讨论。本文旨在为相关研究人员和团队提供未来在该区新布设地震探测台站时的参考, 也可为后续深入研究该区的深部结构与成矿过程提供一些深部要素约束。  相似文献   

宽带多卜勒测流仪(BBADCP)信号特性分析   总被引：11，自引：0，他引：11  

张道平 《海洋技术学报》2001,20(1):78-82

本文介绍了二进制相应编码测流声纳（BBADCP）信号的相关和频谱特性，讨论了有关参数选择的原则。  相似文献   

Acquisition and Inversion of Dispersive Seismic Waves in Shallow Marine Environments   总被引：1，自引：0，他引：1  

Gerald Klein  Thomas Bohlen  Friedrich Theilen  Simone Kugler  Thomas Forbriger 《Marine Geophysical Researches》2005,26(2-4):287-315

Two types of dispersive seismic waves have been acquired in different geological settings to investigate the potential to reveal the elastic parameters of the shallow marine subsurface. Scholte waves as well as acoustic guided waves are excited by a near-surface towed airgun, and recorded using two acquisition methods: (1) the towed-acquisition system using a hydrophone streamer towed close to the sea floor, and (2) the stationary-receiver method using Ocean-Bottom Seismometers and/or Hydrophones (OBS/OBH). Our diverse data sets reveal that the spatial sampling of the wavefield required to avoid aliasing may vary significantly for different geological settings. Scholte waves are characterised by a few distinct modes observed at low frequencies and low phase velocities. Their dispersion is mainly controlled by the depth profile of the shear-wave velocity. Acoustic guided waves show profound amplitude variations of numerous higher modes over a broad frequency range. These are sensitive to shear-wave velocity, but more sensitive to compressional-wave velocity than Scholte waves are. To avoid the identification of distinct modes we infer 1-D models of elastic parameters of the subsurface from the inversion of the full wavefield spectra of acoustic guided waves. In the Siberian Laptev Sea we infer the presence of a soft sediment layer (8–10 m) with a well resolved strong S-velocity gradient (150–450 m/s). In the Baltic Sea a low P-velocity layer with a strong vertical gradient (1250–1440 m/s) corresponding to a post-glacial gassy mud layer could be resolved, which agrees well with the sediment stratigraphy derived from a gravity core.  相似文献