European sessions and datum definitions

In this work we present some preliminary studies to assess a method to investigate the eect of the selection of dierent datums on the adjustment of a geodetic network on a continental scale. In particular we have considered European VLBI sessions. All the experiments since 1990 until the end of 2010 have been processed. The adjustments, session by session, have been performed two times, under the same analysis options but xing two slightly dierent datums. An analysis of estimated 3D coordinates making use of the maximum eigenvalue calculated for each station and each experiment, was carried out. The stability of the results and the in uence of dierent datum choices on the goodness of estimated coordinates have been investigated.