ResumenEl área de estudio comprende la porción noroccidental de la Cuenca de Chicontepec, en el sureste del estado de San Luis Potosí y el noreste de Hidalgo. En las secuencias estratigráfi cas de la Formación Chicontepec del Paleoceno Inferior, en afl oramientos aislados, se interpretaron dos subambientes sedimentarios mayores en el modelo de abanico: el medio y el externo, cuyos criterios para su identifi cación fueron: (a) litoestratigráfi cos (espesor, geometría y distribución); (b) estructuras sedimentarias primarias internas y externas y (c) estructuras por deformación intraformacional. Las facies sedimentarias están compuestas por partículas siliciclásticas y calcáreas provenientes de la Sierra Madre Oriental, al occidente; la paleoisla de Tuxpan, al oriente; el macizo de Teziutlán, al sur; los sedimentos fueron transportados masivamente como deslizamientos, derrumbes, fl ujos de escombros y por corrientes de turbidez y depositados de forma masiva, tabular, lenticular y lobular al pie de talud de la cuenca y en el piso marino. Abstract The study area comprises the northwestern portion of the Chicontepec Basin at southeastern San Luis Potosí and northeastern Hidalgo States. At the stratigraphy sequences of the Chicontepec Formation from Lower Paleocene in isolated outocrops

The Lower Paleogene Chicontepec Foreland Basin at the southern region of the Tertiary Tampico-Misantla Basin at East-Central Mexico, resulting from the loading pressure of the uplifted and thrust-folded front of the Sierra Madre Oriental, on the passive, unfolded and thermally in subsidence Cretaceous basement, during the northeastward tectonic stresses from the Laramide Orogeny, against the Tuxpan Island eastern. The foreland basin consists stratigraphically of complex low density turbidite systems, being their detached and non-channelized outer-fan lobe facies the most conspicuous, composite by disperse and discontinue sandy lenses with tight and highly cemented calcareous lithofacies, micro-fractured and with micro-vugs by dissolution. The hydrocarbons flowed vertically from the underlay Cretaceous and Upper Jurassic rocks through the NW-SE dextral transpressive strike-slip fault planes and fractures, then spread laterally toward the micro-fractured sandy lenses and within the unconformable erosive surfaces, bounding the depositional systems (systems tracts), at different levels of the Chicontepec stratigraphic column, in a hybrid petroleum system with low permeability unconventional reservoirs.