Rhine terrace [9,10] although the normal magnetic polarity of the lava (fluxgate field measurements) suggest the age of the lava to be younger than 0.73 Ma using the most recent paleomagnetic time scale [111. Unresolved discrepancies between the high ages of lavas Hohe Buche (East-Eifel) and Sarresdorf (West-Eifel) overlying low terraces (Niederterrassen) believed to be younger than 0.1 Ma may be due to excess argon. Ultramafic nodules may be the reason for the anomalously high age of the Ruderbfisch lava overlying the Kyll middle terrace [117)], whose age may be only about half that suggested by the present K/Ar data. Oligocene ages of two Tertiary alkali basalts in the East-Eifel extend the area of previously established Oligocene volcanism eastwards [12]. The Miocene age of Arensberg volcano is identical to that found earlier [12]. Middle Tertiary volcanism in the Eifel may have occurred in distinct Oligocene and Miocene phases. The new data corroborate previous suggestions that the postulated Eifel plume [131 is not supported by age data [12, 14]. The age distribution of Quaternary volcanic activity in both East-and West-Eifel does not indicate termination of volcanic activity. Magma and thus heat transfer from the mantle to the crust may still continue. The K/At determinations were carried out by Amdel Laboratories. We thank the Deutsche Forschungsgemeinschaft, the Bundesministerium ftir Forschung und Technologic and the European Commission in Brussels for support of our work.