Project development Global Reference Network

Global Reference Network

Geochemical Reference Network

In order to begin systematic international geochemical mapping it is necessary to establish a primary global Geochemical Reference Network (GRN), analogous to a geodetic grid.  Wide-spaced sampling is required over the entire land surface, including regions already surveyed, and regions where there is low probability of any geochemical mapping being carried out in the near future.  The samples collected will serve as analytical reference materials, so strict procedures must be followed, and adequate quantities must be obtained and retained for future reference and research requirements.


The primary global Geochemical Reference Network (GRN) is based on the Global Terrestrial Network (GTN) or Geochemical Terrestrial Network grid cells of 160x160 km.  Up to now these terms were used as synonyms.  However, it is important to explain the difference among (i) the Global Reference Network, (ii) the Global Terrestrial Network or Geochemical Terrestrial Network (GTN) and (iii) the global Geochemical Reference Network (GRN):


(i)   The Global Reference Network refers to the grid cells of 160x160 km covering the whole globe (land and sea);
(ii)  The Global Terrestrial Network or Geochemical Terrestrial Network (GTN) refers to the grid cells of 160x160 km covering only the terrestrial part of the globe, and
(iii) The global Geochemical Reference Network (GRN) refers to the individual sampling sites within each GTN grid cell of 160x160 km.