Los placeres auriferos de la llanura aluvial del rio Segre y delta del rio Ebro (ne de la peninsula iberica)

The discovery of gold during the geochemical exploration and panning of the Segre River's alluvial fan to determine geochemical background and heavy minera1 types led to an exhaustive study of the entire river basin and that section of the Ebro River where the Segre joints. During the study it was established that the main gold inflows came from the Noguera Pallaresa River (a left tributary of the Segre); that the origin of this gold could be located in Silurian and late Ordovian turbidic materials, as well as skarns and veins of late Hercynian arsenopyrite-gold; and that the greatest accumulation is located in the Segre alluvial fan with geochemical backgrounds high in REE, gold, zirconium and gold, in the Ebro delta.