High-spectral resolution solar microwave observations The data were obtained by: (1) visual observations of selected Earth features, (2) hand-held camera photography to document observations, and (3) stereo mapping photography of areas of significant scientific interest. The discussion is structured according to the fields of investigation including: geology, desert studies, oceanography, hydrology, and meteorology. Observation and photographic data from the Apollo Soyuz Test Project are analyzed. However, it is difficult to distinguish with the present sets of Pn/Sn array data whether (and also where) the boundary layer is a frozen-in feature of paleo-processes or whether it is a response toĮarth observations and photography experiment: Summary of significant results Dynamic stretching of mantle material during subduction or flow, possibly combined with chemical differentiation have to be considered as scale-forming processes in the upper mantle. Their propagation appears to be independent of age. This explains why the Pn and Sn phases traverse geological provinces of various age, heat flow, crustal thickness, and tectonic regimes.
It is shown that wave propagation in the SMBL waveguide is insensitive to the background velocity distribution on which its schlieren are superimposed. It is suggested that the SMBL is of global significance as the physical base of the platewide observed high-frequency phases Pn and Sn. The SMBL consists of randomly distributed, mild velocity fluctuations of 2% or schlieren of high aspect ratios (?40) with long horizontal extent (?20 km) and therefore as thin as 0.5 km only SMBL thickness is 60-100 km. Estimates of the other key elements of the SMBL were obtained by finite difference calculations of wave propagation in elastic 2D models from a systematic grid search through parameter space. Densely recorded seismograms permit recognition of previously unknown features of teleseismic propagation of the well known Pn and Sn phases, such as a band of incoherent, scattered, high-frequency seismic energy, developing consistently from station to station, apparent velocities of sub-Moho material, and high-frequency energy to distances of more than 3000 km with a coda band, incoherent at 10 km spacing and yet consistently observed to the end of the profiles. We infer the fine structure of a sub-Moho boundary layer (SMBL) at the top of the lithospheric mantle from high-resolution seismic observations of Peaceful Nuclear Explosions (PNE) on superlong-range profiles in Russia. Global significance of a sub-Moho boundary layer (SMBL) deduced from high-resolution seismic observationsįuchs, K.
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