In the last years in the area of Cerro Dragón, within to the northern flank of the San Jorge Gulf Basin, untraditional reservoirs began to be exploited in the Mina del Carmen Formation (MdC). They were deposited in a distal or proximal floodplain environment with evidence of hydromorphism that generated alterations during the diagenesis that made possible the dissolution of silica and the presence of secondary porosity. These reservoirs were identified and described by other authors from seismic and environmental point of view; and both are found in the lower section of the MdC B subunit and in the upper section of the MdC A subunit and generically they were referred to as "Logfacies 1" or "LF1". In the present work a detailed analysis of these reservoirs is carried out within the Tres Picos Norte zone belonging to the Cerro Dragón area. It is possible to distinguish 3 facies within these reservoirs from core analysis in the Valle Hermoso analogous deposit and its calibration with the pore size distribution profiles of the NMR. Through implementation of crossplots 3 internal facies are recognized within the stacked reservoirs called LF1: a) The LF1 itself, which correspond to reservoirs developed from alterations of floodplain and have reservoirs with micro and macropores, b) LF2 corresponding to non-Reservoir areas. c) LF3 identified as channeled reservoirs that have meso and macropores. From the internal correlation of these levels, a detailed petrophysical model calibrated with sidewall cores and the identification of these 3 facies, it was possible the mapping where a lateral progression of facies can be observed, ranging from channeled reservoirs to reservoirs of altered floodplain to finally grade to non-reservoir zones. The understanding of the distribution of these reservoirs is very important to reduce the risk of the prospects.