Standards and Reference Materials for intercalibration


There is no longer any GSP or other offshore reference materials. There is plenty of GSC material remaining, which can be sent out on request (see below).

Seawater consensus material GSP and GSC
The community needs to develop consensus values for the GEOTRACES standards GSP (2009 GEOTRACES Pacific surface seawater) and GSC (2009 GEOTRACES coastal surface seawater), since we have no samples left to send out for the original consensus materials.   For those of you who have received GSC and GSP, please report those values to Jim Moffett at  These reported values are held in confidence by Moffett but are vital for our community.

If you require GSC samples, please email Moffett with a request.  To save time, include a Fedex account number with your initial request. If you prefer DHL, please set up the shipment from your end (Moffett will provide you with pickup instructions) and email Moffett a copy of the DHL Waybill with bar code.

While there is no charge for the samples themselves, they were costly to procure. Receipt constitutes an obligation to report values.

Seawater consensus material CAP
Deep water (2500m) from the Cape Basin (CAP) has been cleanly sampled and bottled by GEOMAR (Achterberg/Schlosser) onboard Meteor cruise M121 (GA08) for trace element analysis. Samples of this consensus material (500 mL bottles) will soon be available to those who will supply their values for establishing a consensus value. Once enough laboratories have contributed, consensus values will be published. As for other consensus materials, receipt constitutes an obligation to report values. For obtaining the samples (when available) and to enquire about shipping, please contact

Consensus Reference Materials for Aerosols (Arizona Test Dust, ATD)
Aerosol chemistry, solubility, and flux to the oceans are key parameters in the GEOTRACES Science Plan. Intercalibration is essential for producing aerosol data that will be accepted into any GEOTRACES Intermediate Data Product. Please read this document to learn about the steps to follow for intercalibration as well as for information on how to obtain a sample of the underway effort to utilize Arizone Test Dust (ATD) as a potential “consensus reference material”.

Consensus Values:

GSP and GSC Seawater Samples:

Consensus Values for the GEOTRACES standards GSP (2009 GEOTRACES Pacific surface seawater) and GSC (2009 GEOTRACES coastal surface seawater) are available to download here.

SAFe and North Atlantic Seawater Samples:

Consensus Values for the SAFe and North Atlantic GEOTRACES Reference Seawater Samples are available to download on the table below. Please, read the GEOTRACES Standards and Reference Samples Read Me document before downloading the files:

*Read Me version 2016 (Also see previous Read Me statements: 20112009)

ElementSAFE Reference SamplesMay 2013GEOTRACES Reference Samples May 2013
*Cautionary Note on the Analysis of Seawater for Aluminium