Seismic interferometry refers to the process of retrieving new seismic responses by crosscorrelating seismic observations at different receiver locations. Seismic migration is the process of forming an image of the subsurface by wavefield extrapolation. Comparing the expressions for backward propagation known from migration literature with the Green’s function representations for seismic interf...

the relationship between topography, land use, and topsoil moisture storage is investigated for a small catchment with undulating deep loess hilslopes in the south of the netherlands. for a period of 10 months, soil moisture profiles have been measured weekly at 15 locations throughout the catchment. a generalized additive model was employed to find relationships between the various factors inf...

Several seismic phases that scattered within a few hundred kilometers of the base of the mantle are observed in a very dense seismic section. The Los Angeles Region Seismic Experiment passive phase array was composed of 88 seismometers placed along a 175 km profile. Records from two deep earthquakes in Tonga and one earthquake near Honshu, Japan show a secondary arrival between clear P and PcP ...

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...

We present a real-time procedure that uses cross-correlation and doubledifference methods to rapidly relocate new seismic events with high precision relative to past events with accurately known locations. Waveforms of new events are automatically cross correlated with those archived for nearby past events to measure accurate differential phase arrival times. These data, together with delay tim...

Mature seismic gaps are defined here as gaps in which a possible precursor to a future event has been identified. The seismic potential of these seismic gaps is enhanced relative to immature seismic gaps. The seismic gap hypothesis by itself provides an excellent means of narrowing spatial limits along plate boundaries within which the great earthquakes of the next several decades are expected....

the purpose of velocity analysis is to extract the normal moveout velocity as a function of the zero-offset travel time at selected cdp locations along the seismic line. since results of velocity analysis depend on coherency estimator, an estimator that provides a high velocity resolution is essential. even though the conventional semblance method which is the most popular coherency estimator (...

In this talk I will introduce marine seismic acquisition technologies and focus on solutions to maximize the bandwidth of the measured data. This involves detecting and removing the components of the wavefields that are reflected at the sea surface and that propagate downward: these downgoing reflections, called “ghosts” in literature, interfere with the upgoing wavefield, that is generated by ...

Concerns about potential liquefaction and resulting flowslide type failures at Wickiup Dam in Central Oregon prompted geophysical studies of the left wing dike, studies which included a high resolution seismic reflection survey. High resolution seismic reflection data effectively delineated structures and correlated lithologies to shallow borehole data above the surface of the dipping, basalt b...