The development and progress of fractures is accompanied by the radiation of acoustic waves due to microcracking. In the transient waveforms of acoustic emissions a huge number of information about fracture processes and the state of the material is inherent. Signal-based analysis of acoustic emissions allows, amongst other studies, for a fracture mechanics based investigation of failure. From ...

We explore the use of collocated GPS and seismic sensors for earthquake monitoring and early warning. The GPS and seismic data collected during the 2011 Tohoku-Oki (Japan) and the 2010 El Mayor-Cucapah (Mexico) earthquakes are analyzed by using a tightly-coupled integration. The performance of the integrated results is validated by both time and frequency domain analysis. We detect the P-wave a...

Full waveform inversion of a p ? marine data set from the Gulf of Mexico provides estimates of the long-wavelength P-wave background velocity, anisotropic seismic source, and three high-frequency elastic parameter reeectivities which explain 70% of the total seismic data and 90% of the data in an interval around the gas sand target. The forward simulator is based on a plane-wave viscoelastic mo...

Shallow seismic reflection marine profiles were collected in the area of Balaton Lake in Hungary using high frequency boomer techniques, in order to get information about the stratigraphy of the sedimentary layers. The noise in these shallow marine seismic reflection data is analyzed, and a series of traditional seismic data processing techniques is applied to improve the S/N ratio and coherenc...

Waveform inversion and wave-equation migration velocity analysis share one common feature: both techniques exploit information available in the same source and receiver wavefields reconstructed at all times and at all locations in space. These two wavefields are reconstructed from the same source function and observed data as solutions to the same wave-equation. Both techniques invert for the s...

Spectral decomposition is a powerful analysis tool used to identify the frequency content of seismic data. Many spectral decomposition techniques have been developed, each with their own advantages and disadvantages. The basis pursuit technique produces a high time frequency resolution map through formulating the problem as an inversion scheme. This techniques differs from conventional spectral...

In our last SEP report, we introduced an AVO dataset consisting of seismic, petrophysical and well-log information which was provided by Mobil as part of an AVO workshop (?). The prestack seismic data are heavily contaminated by free-surface and water-bottom multiple reflections, and thus represent a challenge for true-amplitude processing. We described our preliminary preprocessing work and di...

Full waveform inversion of a p-r marine data set from the Gulf of Mexico provides estimates of the longwavelength P-wave background velocity, anisotropic seismic source, and three high-frequency elastic parameter refiectivities that explain 70% of the total seismic data and 90% of the data in an interval around the gas sand target. The forward simulator is based on a planewave viscoelastic mode...

impedance (AI) and a parameter related to shear-wave velocity from seismic data, our ability to discriminate between different lithologies and fluid phases will increase. Prestack inversion on individual CDP gathers and inverting directly for VP, VS, and density have been tested in several ways, but the estimated parameters are often poorly determined. A more robust approach is to apply poststa...

Kirchhoff inversion theory tells us that reflection data provides information about the Fourier transform of the reflectivity function at each point in the illuminated subsurface. Thus, inversion formulas expressed as integrals in image point coordinates that closely characterize that Fourier domain are attractive for their relative simplicity. On the other hand, integrals over source/receiver ...