Combined subsidence and thermal 1D modelling was performed on six well-sections located in the north-western Mid-Polish Trough/Swell in the eastern part of the Central European Basin system. The modelling allowed constraining quantitatively both the Mesozoic subsidence and the magnitude of the Late CretaceousPaleocene inversion and erosion. The latter most probably reached 2,400 m in the Mid-Polish Swell area. The modelled Upper Cretaceous thickness did not exceed 500 m, and probably corresponded to 200-300 m in the swell area as compared with more than 2,000 m in the adjacent noninverted part of the basin. Such Upper Cretaceous thickness pattern implies early onset of inversion processes, probably in the Late Turonian or Coniacian. Our modelling, coupled with previous results of stratigraphic and seismic studies, demonstrates that the relatively low sedimentation rates in the inverted part of the basin during the Late Cretaceous were the net result of several discrete pulses of nondeposition and/or erosion that were progressively more pronounced towards the trough axis. The last phase of inversion started in the Late Maastrichtian and was responsible for the total amount of erosion, which removed also the reduced Upper Cretaceous deposits. According to our modelling results, a Late Cretaceous heat-flow regime which is similar to the present-day conditions (about 50 mW/m 2 ) was responsible for the observed organic maturity of the Permian-Mesozoic rocks. This conclusion does not affect the possibility of Late CarboniferousPermian and Late Permian-Early Triassic thermal events.

a b s t r a c tThe Mid-Polish Trough (MPT) is situated in the easternmost part of the Central European Basin System (CEBS) and stretches NW-SE across the Polish Basin. It was characterised by pronounced subsidence and thick sediment accumulation between the Permian and the Late Cretaceous. Late Cretaceous-early Paleogene basin inversion led to the formation of the Mid-Polish Swell (MPS). The study area is located within the Pomeranian segment of the MPT/MPS (NW Poland) and experienced up to 7 km PermianMesozoic subsidence. PetroMod 1-D modelling was performed on several well-sections in order to study Permian to recent burial-uplift evolution. The modelling was calibrated with new vitrinite reflectance (VR r ) data and allowed to constrain the magnitude of uplift and related erosion as well as provided a first overview of the temperature history. The base of the studied Permian-Mesozoic successions attained maximum burial depths of 4800-5400 m before the onset of the inversion, less than in the axial trough area. The thickness of pre-and most probably also syn-inversion Upper Cretaceous deposits is estimated as 300 m. Erosion associated with inversion processes removed between 900 and 1400 m of the Mesozoic sediments, i.e. 1000-1500 m less than in the most inverted central part of the trough. VR r data suggest constant Permian-Mesozoic heat flows corresponding to present-day values (40-45 mW/m 2 ). Apatite fission-track (AFT) ages modelled with the PetroMod module PetroTracks show a good fit with AFT ages directly measured on well samples, and further support the assumption of steady heat flow in the range 40-45 mW/m 2 . Palaeotemperatures appear to have decreased towards the East European Craton margin, which is compatible with the present day distribution of heat flow. Thermal history modelling shows a relatively simple Permian-Mesozoic heat flow pattern in the Pomeranian segment of the MPT. Such a scenario implies that the present-day heat flow distribution has not changed essentially since Mesozoic times.

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