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...

Seismic denoising is a key step in seismic signal processing for enhancing the resolution of the seismic signal. In this paper, a seismic denoising method is introduced by using variational mode decomposition (VMD) combined with wavelet transform. VMD is used to decompose the seismic data into a series of intrisic mode functions (IMFs) from low frequency to high frequency. Since the noise is al...

In this paper, we present a methodology for interpreting faults from three dimensional seismic data. Faults are individual fractures across which there are visible offsets of horizons (or rock layers). 3D seismic data images of subsurface structure generated by reflecting seismic waves off rock layers have been used for hypothesizing subsurface structures. Since interpretation of seismic data i...

In seismic data processing, deconvolution plays a very important role because it permits to increase the temporal resolution of seismic sections and to equalize sources. The deconvolution problem when the wavelet is known is an ill-posed problem that can be tackled via regularization methods. However, the seismic source wavelet is unknown and therefore, it must be estimated from the data prior ...

The primary objective of the work-in-progress reported here is to compare near-surface imaging results using ultra-shallow (upper 3 m) seismic-reflection techniques and ground-penetrating radar (GPR) at an alluvial site near Great Bend, Kansas. Although various seismic and GPR surveys have been used for near-surface imaging, little i s known about how the two techniques might work in concert fo...

S U M M A R Y We propose a new, simple and efficient method to image electrical resistivity between a set of wells. Our procedure consists of two steps: first, we map the interfaces between various subsurface formations using seismoelectric conversions; second, we derive the formation resistivity using image-guided cross-well electric tomography. In the first step, we focus seismic energy at a ...

We review the resolution currently available with seismic tomography, in particular the ability of seismic waves to image mantle plumes, and discuss frequently asked questions about artifacts, interpretation and possible systematic errors. These aspects are discussed in more detail for two case histories offering different problems in the tomographic interpretation: Iceland and Hawaii. Regional...

In recent years, there has been an increase in the deployment of relatively dense arrays of seismic stations. The availability of spatially densely sampled global and regional seismic data has stimulated the adoption of industry-style imaging algorithms applied to convertedand scattered-wave energy from distant earthquakes, leading to relatively high-resolution images of the lower crust and upp...

refractor ambiguities are big problem in seismic refraction method especially in seismic engineering. there can be hidden subsurface geological phenomena such as hidden faults and shear zones which are not simply predicted by the travel-time graph or some geophysical methods. head wave amplitudes are used to show the resolution of refractor ambiguities and the existence of anisotropy in complex...