RAY VELOCITIES IN TRANSVERSELY ISOTROPIC MEDIA, FROM COMMON-OFFSET REFLECTION DATA
S.N. Medvedev
Pacific Institute of Oceanography, Far East Branch of the RAS, 43 ul. Baltiiskaya, Vladivostok, Russia
Keywords: Ray velocity, velocity indicator function, anisotropy, inversion
Pages: 101-118
Subsection: GEOPHYSICS
Abstract
The relationship between layer and apparent reflection velocities obtained for a layer much thinner than the overlying in a 2D transversely isotropic medium can be used to plot offset dependence of effective ray velocity indicative of anisotropy type. This approach, called point inversion, is based on the properties of two rays which are reflected from the layer top and bottom and connect a single source-receiver pair. Point inversion is applied, after constraining the layer thickness, to obtain the indicator function of ray velocity and then to find the horizontal velocity and anisotropy in each layer. Processing of seismoacoustic radio buoy data acquired in marine sediments and numerical modeling show up to 16 percent anisotropy of type 2.
|
