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| Format: | Dataset Open Access |
| Language: | en |
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PANGAEA
2024
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| Online Access: | https://doi.org/10.1594/PANGAEA.967374 |
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| _version_ | 1867168525360037888 |
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| author | Novak, Joseph B Caballero-Gill, Rocio P Rose, Rebecca Herbert, Timothy D Dowsett, Harry J |
| author_facet | Novak, Joseph B Caballero-Gill, Rocio P Rose, Rebecca Herbert, Timothy D Dowsett, Harry J |
| collection | Datos científicos de ciencias marinas y ambientales |
| contents | Here we present new splice for the late Pliocene interval site 883 hole B. 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 depth mbsfc once. The other option is to go directly from depth mbsf to depth mcd. To do this, one will have to interpolate the data for each core of hole B and hole C seperately. The reason for this being that there is significant overlap between cores on the depth mbsf scale that were drilled in the same hole, so if one interpolates all the data from all the cores in hole B, for example, to depth mcd at once, one will notice in your data table that data from, for example, 883 B 17H section 7 is overlapping with data from 883B 18H section 1. This is obviosly wrong - the way to fix it is to use the mcd scale tiepoints from each core seperately rather than all together. |
| format | Dataset Open Access |
| id | pangaea_https___doi_org_10_1594_PANGAEA_967374 |
| institution | PANGAEA |
| language | en |
| publishDate | 2024 |
| publisher | PANGAEA |
| record_format | pangaea |
| spellingShingle | New splice for the late Pliocene interval ODP Hole 145-883B Novak, Joseph B Caballero-Gill, Rocio P Rose, Rebecca Herbert, Timothy D Dowsett, Harry J 145-883B; Age model; Alkenones; Benthic foraminifera assemblages; Benthic foraminiferal stable isotopes; Calcium Carbonate content; Composite splice; Depth, composite; Depth, compressed; DEPTH, sediment/rock; diatoms; DRILL; Drilling/drill rig; DSDP/ODP/IODP sample designation; Joides Resolution; Leg145; North Pacific Ocean; Ocean Drilling Program; ODP; ODP 883; ODP 887; Sample code/label; Stable carbon isotopes δ13C; stable oxygen isotopes; Subarctic North Pacific; Uk'37 sst and C37total Here we present new splice for the late Pliocene interval site 883 hole B. 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 depth mbsfc once. The other option is to go directly from depth mbsf to depth mcd. To do this, one will have to interpolate the data for each core of hole B and hole C seperately. The reason for this being that there is significant overlap between cores on the depth mbsf scale that were drilled in the same hole, so if one interpolates all the data from all the cores in hole B, for example, to depth mcd at once, one will notice in your data table that data from, for example, 883 B 17H section 7 is overlapping with data from 883B 18H section 1. This is obviosly wrong - the way to fix it is to use the mcd scale tiepoints from each core seperately rather than all together. |
| title | New splice for the late Pliocene interval ODP Hole 145-883B |
| topic | 145-883B; Age model; Alkenones; Benthic foraminifera assemblages; Benthic foraminiferal stable isotopes; Calcium Carbonate content; Composite splice; Depth, composite; Depth, compressed; DEPTH, sediment/rock; diatoms; DRILL; Drilling/drill rig; DSDP/ODP/IODP sample designation; Joides Resolution; Leg145; North Pacific Ocean; Ocean Drilling Program; ODP; ODP 883; ODP 887; Sample code/label; Stable carbon isotopes δ13C; stable oxygen isotopes; Subarctic North Pacific; Uk'37 sst and C37total |
| url | https://doi.org/10.1594/PANGAEA.967374 |