. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. SOUNDINGS TAKEN DURING THE DISCOVERY INVESTIGATIONS, 1932-1939 Si but soft ooze will often fail to return more than a faint whisper, which only an operator with much experience can distinguish from other noises. The strength of the signal returning from a hard or rock bottom has often been sufficient to cause re-echoes, and many have been recorded from quite considerable depths. In one instance, on 8 March 1938, at St. 2277 (65° 19-6' S, 81' 42' W) a clear re-echo was heard at twice the observed
. Discovery reports. Discovery (Ship); Scientific expeditions; Ocean; Antarctica; Falkland Islands. SOUNDINGS TAKEN DURING THE DISCOVERY INVESTIGATIONS, 1932-1939 Si but soft ooze will often fail to return more than a faint whisper, which only an operator with much experience can distinguish from other noises. The strength of the signal returning from a hard or rock bottom has often been sufficient to cause re-echoes, and many have been recorded from quite considerable depths. In one instance, on 8 March 1938, at St. 2277 (65° 19-6' S, 81' 42' W) a clear re-echo was heard at twice the observed depth of 2428 fm. (4440 m.). If the soundwave is of sufficient strength to echo again between the hull of the ship and the bottom at this depth, and then provide a clearly audible signal on its second return, it would appear that there should be ample reserve of power to provide an echo even from a moderately soft bottom. Immediately south of the Convergence, however, the deposit is almost pure diatom ooze and it apparently lies on the bottom as a very soft covering, the upper part of which is flocculent and comparable to a very thick soup. At St. 2519, in 51° 57-8' S, 19° 32' E, the bottom reversing water bottle of the deep hoist apparently hit bottom and brought up an excellent sample of this liquid ooze from 2865 m. (1567 tm.).. Fig. 6. 0° Line, February-March 1939. Vertical distribution of density in terms of tr,. Antarctic Convergence in, approximately, latitude 49° 33' S. Generally, it may now be said that a belt of diatom ooze surrounds the globe in the southern hemisphere and that its northern limit approximates closely to the northern limit of the Antarctic Convergence (see Hart, 1934, pp. 185-6 and Deacon, 1945, pp. 11-20). We thus find in the neighbourhood of the Antarctic'convergence that there may be two important factors which will cause weak echoes, the horizontal trend of the discontinuity layers north of the line of the Convergence, and the bottom de
Size: 2138px × 1169px
Photo credit: © Paul Fearn / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, booksubjectocean, booksubjectscientificexpediti
