Text: The Helmholtz equation is frequently used as f model for sonic inversion for both geophysical and medical applications. In this paper we describe explicitly the use of multi-sources, i.e., the simultaneous 'firing' of all transducers for the case of medical, and all geophones for the case of geophysical inversion, resulting in a novel inversion procedure that enabling the circmumvention o...

The Inversion Algorithm is an event driven algorithm whose performance meets or exceeds that of traditional compiled-code simulators. However, existing implementations of the algorithm do not allow several vectors to be packed into a single word, thus limiting the power of the algorithm. Because the Inversion Algorithm does not represent net values in the conventional way, the simple packing te...

To better interpret the subsurface structures and characterize reservoir, a depth model quantifying P-wave velocity together with additional rock’s physical parameters such as density, S-wave velocity, anisotropy is always preferred by geologists engineers. Tradeoffs among different can bring extra challenges to seismic inversion process. In this study, we propose test Direct Waveform Inversion...

[1] Taking advantage of large datasets of both gravity and elastic wave arrival time observations available for the Parkfield, California region, we generated an image consistent with both types of data. Among a variety of strategies, the best result was obtained from a simultaneous inversion with a stability requirement that encouraged the perturbed model to remain close to a starting model co...

air pollution is one of the most important problems in urban areas that always threaten citizen's health. photochemical smog is one of the main factors of air pollution in large cities like tehran. usually smog is not only a part of nature, but is being analyzed as an independent matter, which highly affects on the nature. it has been used as relationship between atmospheric elements such as te...

As one of the few deep-earth imaging techniques, magnetotellurics provides information on both the structure and physical state of the crust and upper mantle. Magnetotellurics is sensitive to electrical conductivity, which varies within the earth by many orders of magnitude and is modified by a range of earth processes. As with all geophysical techniques, magnetotellurics has a non-unique inver...

This is the second paper in a two-part series that describes a massively parallel code that performs 2D full-waveform inversion of wide-aperture seismic data for imaging complex structures. We present several numerical validation of the full-waveform inversion code with both canonical and realistic synthetic examples. We illustrate how different multiscale strategies can be applied by either su...