2

Models for the Tamabra Limestone of the Poza Rica field (Figure 1) initially indicated a ‘reef ’ system downfaulted from its original depositional position alongside the Tuxpan Platform. This was based on the facies encountered in the most highly productive core of the field (Salas, 1949; Barnetche and Illing; 1956, Gúzman, 1967, Coogan et al., 1972). However, work carried out during the late 1960’s and 1970’s which integrated ne