th234_bottle

 PI:              Jennifer Young, James Murray
 of:              University of Washington
 dataset:         Isotope activity, Go-Flo bottle samples
 project/cruise:  EqPac/TT007, Survey 1
 ship:            R/V Thomas Thompson
 
 Thorium-234 Sampling Methodology
 Isotope Sampling Methodology
 
  
DMO notes:

 Dr. Murray's documentation states that the samples for dissolved and particulate
 fractions were filtered using either a 0.45 or 0.50 micron filter.  Since the 
 samples were not flagged as to filter size, they all have been identified 
 as being filtered at 0.45 microns. 
 
 The 226Ra data comes from a Ra-Si regression determined from Teh-Lung Ku 
 (University of Southern California) 226Ra data reported from samples 
 taken at the same stations.

 The principal investigators have arranged the data to display depth
 profiles at nominal geographic station locations. The composite profiles
 have been assembled from three or more casts within a given station/location.


 Parameter          Description                                   Units

 sta                station number from event log
 lat_n              nominal latitude, minus = South               degrees
 lon_n              nominal longitude, minus = West               degrees 
 depth_n            nominal depth of sample                       meters
 Ra226_SiO4         Radium-226 as determined by a Ra-Si           dpm/m3
                    regression determined from 226Ra data at the  
                    same station (see Murray documentation)
 Th234_tot          thorium-234, total                            dpm/m3
 Th234_diss_lt0.45  thorium-234, dissolved lt0.45 microns         dpm/m3
 Th234_part_gt0.45  thorium-234, particulate gt0.45 microns       dpm/m3
 Pb210_tot          lead-210, total                               dpm/m3
 Pb210_diss_lt0.45  lead-210, dissolved lt0.45 microns            dpm/m3        
 Pb210_part_gt0.45  lead-210, particulate gt0.45 microns          dpm/m3
 Po210_tot          polonium-210, total                           dpm/m3
 Po210_diss_lt0.45  polonium-210, dissolved lt0.45 microns        dpm/m3        
 Po210_part_gt0.45  polonium-210, particulate gt0.45 microns      dpm/m3        
 U238_tot           uranium-238, total                            dpm/m3
 PMC                particulate matter concentration              milligrams/m3

 nd indicates missing or bad data