most geologic changes have a seismic response but sometimes this is expressed only in certain spectral ranges hidden within the broadband data. spectral decomposition is one of the methods which can be utilized to help interpreting such cases. there are several time-frequency methods including: short-time fourier transform (stft), continuous wavelet transform (cwt), wigner-ville distribution (w...

-A new method is presented for the texture analysis and segmentation of seismic images. The texture of a seismic image is described in terms either of seismic horizons' features (e.g. length, reflection strength, geometrical appearance), or in terms of Hilbert transform features (magnitude, phase, instantaneous frequency) or in terms of features related to the generalized runs. Seismic image se...

Seismic interferometry is a technique that allows one to reconstruct the full response from a virtual source inside a medium, assuming a receiver is present at the virtual source location. We describe a method that creates a virtual source inside a medium from reflection data measured at the surface, without needing a receiver inside the medium and, hence, presenting an advantage over seismic i...

The case studied in the paper proves that thickening the pile cap is an effective seismic retrofit alternative to strengthen a pile group foundation. Unlike the typical seismic retrofitting of foundation, the proposed method eliminates the need to drive long piles into existing bridge substructures, substantially reducing cost, construction time and traffic interruption. The method thickens the...

Detection of subsurface structures by means of gravity method can be used to determine mass distribution and density contrast of rock units. This distribution could be detected by different geophysical methods, especially gravity method. However, gravity techniques have some drawbacks and can't be always successful in distinguishing subsurface structures. Performance of the gravity technique co...

Hydrocarbon production modifies the stress conditions in the subsurface and changes the model parameters previously estimated from the prospect. The capability to remotely monitor the changes in the reservoir using seismic data has strategic importance since it allows us to infer fluid movement and evolution of stress conditions, which are key factors to enhance recovery and reduce uncertainty ...

Seismic isolation is a method to reduce the destructive effects of earthquakes on a structure in which the structure is separated from its foundation by devices called seismic isolators. As a result, the horizontal movements of the earthquake transmitted to the structure are reduced. The seismic isolation is used for both newly constructed structures as well as for retrofitting the existing bui...

Introduction The seismic frequency band can be defined from 0.3 mhz to tens or hundreds of hz, in which the lower limit is defined by the period of the gravest observed free mode of the Earth (0s2). Digital seismic recordings in this frequency band always contain noise, which essentially can be attributed to ambient Earth noise and instrumental noise, or self-noise, of the recording system. Ins...

Computer-aided fault imaging and interpretation is a fundamental tool for subsurface structure characterization and modeling, and the existing methods are primarily based on seismic discontinuity analysis (e.g., coherence and semblance) that evaluates the lateral variation of waveform and/or amplitude. However, such attributes have a limited resolution on subtle faults without apparent displace...

Aseismic design of gravity wall still is a more difficult issue. The reason stems from the complexity of the problem which requires skills in soil mechanics, foundation engineering, soil-structure interaction along with knowledge of structure dynamics. Designing seismic gravity retaining structures deals with both kinematic interaction and inertial interaction but almost seismic building code n...