The presence of gas hydrate and associated gas in the Makran Accretionary Prism, offshore Iran, has been confirmed by various seismic indicators, including the bottom-simulating reflector (BSR), amplitude blanking, and bright spot. The pre-stack analysis and the study of amplitude-variation-with-offset (AVO) attributes are the most reliable tools for semi-quantitative study of gas hydrate and f...

seismic tomography is an imaging technique which creates maps of subsurface elastic properties such as p/s wave velocity, density and attenuation, based on observed seismograms and use of sophisticated inversion algorithms. amongst different acquisition geometries, seismic cross-hole tomography has a special position in geophysical surveys with many applications in hydrocarbons, coal and other ...

Determination of Geostatistical Parameters Using Well Test Data — In this paper we describe a new method to obtain estimations of the geostatistical parameters (GPs) such as the correlation length, lc and the permeability variance, σln from well test data. In practical studies, the GPs are estimated using geological and petrophysical data, but often, these data are too scarce to give precise re...

The paper outlines a probabilistic basis for the automatic estimation from observed surface wave dispersion of structural model parameters with uncertainties. Given an earth model, a wave type and pertinent parameter values, the group velocity of seismic waves can be computed from theory as a function of frequency. Such a function may also be based on the dynamic spectrum representation of an e...

We propose in this paper a modular approach for the problem of traveltime inversion or seismic tomography. This problem consists in the inference of the velocity of wave propagation in the subsurface after an explosion has been produced at the surface, relying on such waves’ traveltimes. These traveltimes are recorded by several receivers on the surface. In the present work, we consider data sy...

It has been proposed that in the case of strong multiple scattering, the data matrix P is replaced by its inverse P−1 before starting seismic processing. In the inverse data space, all surface-related multiples map onto the origin, whereas the inverse of the primaries map mostly at negative times. This interesting property opens up new ways to separate primaries from multiples and apply other p...

pore pressure could be estimated prior to drilling using seismic velocities. applying this approach, the final calculated pore pressure is highly affected by accuracy of the obtained velocity data. in order to generate an accurate velocity cube with proper resolution, velocities from well logs and post-stack 3-d seismic inversion are used along with stacking velocities from velocity analysis of...

In order to make the seismic positioning and monitoring system work more effectively, this paper designs four kinds of geophone array methods. By establishing complex geological model and using micro-grid ray tracing, the process that the signal starts from the source location to the seismic geophone arrays is simulated in forward algorithm. In condition of random disturbance, the source locati...

We have detected a continuous seismic signal near 2.08 Hz using data from a portable seismic array, 1280 km long, deployed in Siberia and Mongolia. The signal can be observed on almost all the stations along the profile. The amplitude and the frequency of the signal show a clear daily cycle, and their temporal variations are similar at different stations, suggesting that the signals observed at...