| Summary: | Here we present new splice for the late Pliocene interval site 883 hole C. The composite depth scale was created by visual correlation of the shipboard gamma ray attenuation and porosity evaluator (GRAPE) wet bulk density (WBD) measurements between 883B and 883C starting at core 9H and ending at 18H. 883B 11H-1 0–57 cm, 883B 12H-1 0–10 cm, 883B 15H-1 0–20 cm, 883C 15H-1 0–5 cm were not considered in the correlation exercise because the recovered sediments had sidewall cave-in characterized by pebbles typical of the overlying Pleistocene sediments. In almost all cores, recovery was > 100%. To account for this in terms of depth, cores with > 100% recovery were compressed uniformly and fixed to the top drill log depth (depth mbsf) assigned to that core. Subsequent correlation of cores between holes B and C revealed apparent gaps in recovery. Cores were further uniformly compressed to account for the unrecovered sediments and a composite stratigraphic section was stitched together by switching between the two holes. On average, cores were compressed 17% and at most by 28% of their drilled depth (9.5 m). GRAPE WBD from 883B and 883C was then correlated to the composite section to generate tie points for each core to the composite section. The result of this exercise is a composite section of comparable depth to the driller's shipboard depth scale (109.4 meters below sea floor vs. 108.3 meters common depth) that accounts for all the major stratigraphic features present in the GRAPE WBD profiles of 883B and 883C Depth mbsf can be converted to depth MCD using two methods, depending on preferences. The first is to convert all your depth mbsf values to depth mbsfc. To do that, one must go to the site 883 initial report and compress all the cores by the amount of core expansion greater than 9.5 m (i.e., > 100%). One can then use the splice tiepoints to convert from depth mbsfc to depth mcd that are listed in the table. The advantage of this approach is that you only have to interpolate the data from depth mbsf to ...
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