Analysis of Soviet DSS Records for Propagation and Modeling of Lg Blockage across Major Crustal Features
To develop our model, we analyze the data obtained using 42 chemical explosions along the profile. Applying a travel-time tomographic inversion method, we developed a velocity model and estimates of its resolution. Two important resolved features of the model are: 1) high velocity block at the base...
Main Authors: | , |
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Other Authors: | |
Format: | Text |
Language: | English |
Published: |
1997
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Online Access: | http://www.dtic.mil/docs/citations/ADA329400 http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=ADA329400 |
Summary: | To develop our model, we analyze the data obtained using 42 chemical explosions along the profile. Applying a travel-time tomographic inversion method, we developed a velocity model and estimates of its resolution. Two important resolved features of the model are: 1) high velocity block at the base of the crust under the Baltic Shield, 2) crustal roots under the Ural Mountains. Using the data from 3 nuclear explosions in the profile we developed a 2-D upper mantle P-wave velocity model. The model supports the conclusion of the roots under the Urals, and suggests a southeast dipping interface at about 80 km in the upper mantle. A high-frequency phase following teleseismic Pn from the PNEs is interpreted as a "whispering-gallery" phase and is used to estimate attenuation within the upper mantle. Lg from 2 PNEs is blocked between sedimentary basins and the Ural Mountains. A marine-land profile recorded from the Barents Sea to the Kola Peninsula shows a crustal thickness of about 38-40 km at the coast. |
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