The Rio Neuquén block is located 30 km Northwest of Neuquén city and is currently in a development phase of tight gas reservoirs of Punta Rosada and Lajas formations. These formations are composed of a succession of sandstones, siltstones and conglomerates, deposited in a deltaic to marginal fluvial and marine environment. These sediments are over than 1200 m thick and its structure responds to an anticline product of a tectonic inversion. The source rock, Los Molles formation, loads these deposits by direct contact and faults, reaching an overpressure up to 60%. Previous seismic characterization studies include an azimuthal seismic inversion for these two formations and a previous pore pressure model was carried out by the companies Pampa Energia S.A. and Schlumberger S.A. between 2015 and 2017. The pore pressure model, compared to measurements in new wells, overestimates the recorded pressure values. Between 2020 and 2021, a new pre-stack inversion was carried out using a 3D seismic volume of time-scaled PSDM gathers and incorporating profiles from 8 new wells. The results were used to calculate a new pore pressure volume using Eaton’s methodology calibrated with 42-wells. The uncertainty of the pore pressure volume was estimated using error propagation method, establishing a confidence band around 20 percent. The difference between the actual pressure measurements and the calculated values was quantified. Although both models are within the confidence interval, the new volume substantially minimizes the error. The Pore Pressure Volume complements existing tools for new well proposals.