Abstract
Zalecze and Zuchlow are strongly depleted natural gas fields in aeolian sandstones of the Rotliegend, located in the central part of the Fore-Sudetic Monocline. A set of three static 3D models was generated to check the possibility of CO2 injection for Enhanced Gas Recovery (EGR) and to check the safety of storage by means of geomechanical modeling: one regional model (ZZA) and two local models - the first for Zalecze (ZA) gas field and the second for Zuchlow (ZU) gas field. The regional model is composed of 12 stratigraphic complexes (zones) from the base of the Rotliegend to the ground surface. The local models comprise only the three lowermost complexes: fluvial deposits of the Rotliegend, aeolian sandstones of the Rotliegend (Reservoir I) and basal Zechstein limestone, Ca1. The key elements of the modeling procedure include: Quality Control (QC) of the data, interpretation of missing parameters necessary for static modeling and their integration within a geomodel. The processing workflow was elaborated to produce convergent regional and local models. The regional static model is a framework for a regional geomechanical model. The local models are the basis for dynamic simulations and local geomechanical modeling. The presented workflow could be used with some changes for geomodeling of many mature gas and oil fields.