The assumption that the Sr ratio of the world’s oceans has fluctuated uniformly through time has enabled a Global Standard Strontium Curve (GSSC) to be established (Howarth and Mc Arthur, 1997).
Since Sr is taken up by aquatic organisms in equilibrium with the surrounding water it is possible to use their fossilised remains as a proxy for oceanic seawater.
Strontium isotope stratigraphy is now an established technique which provides a numerical age related to a global scale based on the Sr ratio of past seawaters.
Suitable material includes molluscs, foraminifera, conodonts, fish teeth and calcareous algae.
whole rock samples (carbonates, dolomitised carbonates and evaporites) for analysis providing any diagenesis was early.
From 1950 to 1953 he was the Secretary-General of the Rassemblement Democratique Africain (RDA) and helped establish the first Pan-African Student Congress in Paris in 1951. In 1974, a milestone occurred in the English-speaking world when the African Origin of Civilization: Myth or Reality was finally published.
He also participated in the First World Congress of Black Writers and Artists held in Paris in 1956 and the second such Congress held in Rome in 1959. Diop continued his research and established a radiocarbon laboratory in Dakar. It was also in 1974 that Diop and Theophile Obenga collectively and soundly reaffirmed the African origin of pharaonic Egyptian civilization at a UNESCO sponsored symposium in Cairo, Egypt.
This is matched by world class analysis at one of a number of laboratories.