Platinum-group elements in the cores of potassium feldspar spherules from the Cretaceous-Tertiary boundary at Caravaca (Spain)

• Autores: Miguel Ortega Huertas
• Localización: Estudios geológicos, ISSN 0367-0449, Vol. 50, Nº 1-2, 1994, págs. 3-8
• Idioma: inglés
• Enlaces
  • Texto completo
• Resumen

  • The abundant spherules present in the Cretaceous-Tertiary boundary layer at Caravaca are diagenetically transformed to potassium feldspar. Before our study no posssible relicts of the precursor material had been reported, but in this paper we describe the presence of cores in these spherules that could represent a relict of the "unknown precursor". These cores are made up of C mixed with Si, Mg, Al, Cr, Ca among other elements. Laser Ablation System analysis also reveals an enrichment in PGE could suggest an extraterrestrial origin for this material. Pt, Pd and Ir do not show a chondritic ratio; however, a severe modification of their concentration could be expected during the early diagenetic processes