Data Processing:
The measured 143Nd/144Nd isotope ratios were normalized to those of the JNdi-1 Nd standard (0.512115, Tanaka et al., 2000). Please see attached methodology files for further information on the data processing.

BCO-DMO Processing Notes:
- Added the sample_GEOTRC column by copying the original sample column and removing the '_2' from sample duplicates.
- Added Cast_ISO_DateTime_UTC from the original date and time fields.

SUMMARY OF CORRECTIONS MADE TO SUBMITTED DATA:

2017-07-17: parameter descriptions revised as per request by R. Anderson: ND_143_ND_144RATIO and int_ND_143_ND_144RATIO.

version 8: The data for version 8 (April 2016) completely replaced those from version 7.
- The quality flag scheme was changed in accordance with ODV.
- New parameters: EPSILON_Nd, EPSILON_ND_FLAG_W, EPSILON_ND_2SD, Instrument, and Reference were added which are described in the documentation.
- Column cruise_part was removed.
- Version 8b: changed quality flags for KN204-01, stations 3 and 8 from 0 to 2

- 07 March 2013: Made the following corrections after consulting with dataset scientist:

KN199-04
-- Changed cast number of event 3176 from 2 to 8.
-- Changed cast number of event 3169 from 8 to 2.
-- Changed event number of KN199-04 station 3 cast 6 from 2059 to 2061.
-- Changed event number of KN199-04 station 7 cast 6 from 2107 to 2132.
-- Changed event number of KN199-04 station 9 cast 3 from 2059 to 2165.
-- Changed event number of KN199-04 station 10 cast 6 from 2191 to 2194.
-- Changed event number of KN199-04 station 11 cast 6 from 2206 to 2208.
-- Changed bottle number of sample #5393 from 5 to 4 (station 5, cast 6).
-- Changed bottle number of sample #5394 from 4 to 3 (station 5, cast 6).
-- Changed time of event #2024 from 2129 to 1202.

KN204-01
-- Changed bottle number of sample #7955 from 8 to 9 (station 22, cast 4).

Additional data and revisions were served 19 Sept. 2013.

version 9: The last version (8b) of the dataset was split into three datasets by LAB. LDEO, UH, and USC.
See USC dataset: https://www.bco-dmo.org/dataset/3832
LDEO dataset: https://www.bco-dmo.org/dataset/780582

Additional GEOTRACES Processing:
After the data were submitted to the International Data Management Office, BODC, the office noticed that important identifying information was missing in many datasets. With the agreement of BODC and the US GEOTRACES lead PIs, BCO-DMO added standard US GEOTRACES information, such as the US GEOTRACES event number, to each submitted dataset lacking this information. To accomplish this, BCO-DMO compiled a 'master' dataset composed of the following parameters: station_GEOTRC, cast_GEOTRC (bottle and pump data only), event_GEOTRC, sample_GEOTRC, sample_bottle_GEOTRC (bottle data only), bottle_GEOTRC (bottle data only), depth_GEOTRC_CTD (bottle data only), depth_GEOTRC_CTD_rounded (bottle data only), BTL_ISO_DateTime_UTC (bottle data only), and GeoFish_id (GeoFish data only). This added information will facilitate subsequent analysis and inter comparison of the datasets.

Bottle parameters in the master file were taken from the GT-C_Bottle_GT10, GT-C_Bottle_GT11, ODF_Bottle_GT10, and ODF_Bottle_GT11 datasets. Non-bottle parameters, including those from GeoFish tows, Aerosol sampling, and McLane Pumps, were taken from the Event_Log_GT10 and Event_Log_GT11 datasets. McLane pump cast numbers missing in event logs were taken from the Particulate Th-234 dataset submitted by Ken Buesseler.

A standardized BCO-DMO method (called "join") was then used to merge the missing parameters to each US GEOTRACES dataset, most often by matching on sample_GEOTRC or on some unique combination of other parameters.

If the master parameters were included in the original data file and the values did not differ from the master file, the original data columns were retained and the names of the parameters were changed from the PI-submitted names to the standardized master names. If there were differences between the PI-supplied parameter values and those in the master file, both columns were retained. If the original data submission included all of the master parameters, no additional columns were added, but parameter names were modified to match the naming conventions of the master file.

See the dataset parameters documentation for a description of which parameters were supplied by the PI and which were added via the join method.

Nd_GT10-11_v8b_joined.csv