PRE-SANTONIAN CAMPANIAN AGE FOR THE OBDUC TION OF THE GUATEMALAN OPHIOLITES

South of the Polochic fault, the Cerro Tipon shows that the allochthon ous Cretaceous serpentinites are thrust upon Precambrian and/or Palaeo zoic micaschists and Mid-Cretaceous marbles. An upper age limit for th is structuration is indicated by overlying limestones of Santonian-Cam panian age. It thus appears that ophiolite obduction south of the Polo chic Fault predates ophiolite emplacement onto the Maya Block north of the Polochic fault.