Dear Dr. Vaquer-Sunyer,

Our calcareous sediments were analyzed by X-ray fluorescence spectrometry (XRF).

Powdered samples were analyzed using a PANalytical Axios and a PW2400 spectrometer. Samples are prepared by mixing with a flux material and melting into glass beads. The beads are analyzed by wavelength dispersive x-ray fluorescence spectrometry (WD-XRF). To determine loss on ignition (LOI) 1000 mg of sample material are heated to 1030 °C for 10 min. After mixing the residue with 5.0 g lithium metaborate and 25 mg lithium bromide, it is fused at 1200 °C for 20 min. The calibrations are validated by analysis of Reference Materials. "Monitor" samples and 130 certified reference materials (CRM) are used for the correction procedures.

Good luck !

Harald G. Dill

Dear Dr. Dill,

Thanks a lot for your response.

I am afraid we don't have WD-XRF available at our University.

Thank you!

Dear Elsa,

Thank you very much! sounds really useful!

Dear Raquel,

This is one of the paper which can be useful for you. They have described the phosphorous extraction in detail and in a easier way by graphic representation. Hope this help you. https://www.researchgate.net/publication/280445520_Phosphorus_speciation_and_sedimentary_phosphorus_release_from_the_Gulf_of_Mexico_sediments_Implication_for_Hypoxia

Thanks 

Wokil Bam 

Article Phosphorus speciation and sedimentary phosphorus release fro...

Thanks a lot Wokil!