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weak arrivals at distances of ~32-39 (shots 1610-1580). Combined with rough topography at sh. 1575 may obscure cross over. No clear Pn, PmP interesting secondary phase ~1 second behind first arrival. At close range (<20km) signal converges toward 1st arrival. Clearer at low frequencies Strong arrivals at range >40km. At high frequencies (bp2-16) < is clear at shot 1550, range=~45 |