Análisis estratigráfico secuencial de las formaciones Anacleto y Allen (Cretácico Tardío) en el borde nororiental de Cuenca Neuquina, Argentina

based on a detailed sedimentological study we carried out a sequential stratigraphic analysis of the upper cretaceous deposits of the anacleto formation and lower member of the alien formation in the north-eastern border of the neuquina basin. the lithofacies association allowed interpre-ting architectural elements of fluvial origin and tide influenced elements. three fluvial systems (a braided system, an anastomosed one, and a high sinuosity one), a proximal and a middle estuarine system were recognized for the anacleto formation. a distal estuarine system or estuary outlet was defined for the basal member of the alien formation. in the sequential stratigraphy analysis the following systems were identified: a low accommodation system tract in a continental environment limited by a flooding fluvial surface (discontinuity i) and discontinuity ii; and a high accommodation system tract and its equivalent transgressive system tract in a marine environment, with discontinuities iii, iv y v.