How to deal with history ocean station data

[Chi <chi@xxxxxxxxx>]

Hi dear LAS users
   I have the ocean station data for nitrate from 1965 to 2000, which was downloaded from NOAA world ocean database web site at http://www.nodc.noaa.gov/OC5/SELECT/dbsearch/dbsearch.html
   The nitrate data was collected in different areas lon/lat/depth and in different years. For instance, some data was collected in area 1 only at 1970 and 1983. And the areas ( lon/lat) were not uniformly distributed.  I don't know how to proceed on this dataset. So far my previous LAS experience was that I did 3D interpolation on a profile dataset and managed to make LAS work on it.
   Anybody can give me some suggestions or information? Any help will be appreciated.
   Thanks a lot, Ding