Association Of Phosphates With Tuffites In A Core Of Sediments from The Sea Of Japan

摘要

One of the hypotheses on the origin of phosphorites suggests that products of volcanic and hydrothermal activity are phosphorus sources . The cases when phosphorites are associated with volcanic rocks were adduced as evidence in support of this hypothesis. However, some opponents do not consider these facts as indications of the cognation of phosphorites and volcanic rocks .