U, Th and Pb systematics in petroleum systems: first analyzes of petroleum source rocks by fs-LA-ICP-MS Gourlan, A. T. ; Ricard, E. ; Pecheyran, C. ; Prinzhofer, A. ; Donard, O. F. X. Abstract Publication: Geochimica et Cosmochimica Acta Supplement Pub Date: June 2009 Bibcode: 2009GeCAS..73Q.458G