The in-situ stress, and in particular the minimum principal stress, is a major controlling parameter for many subsurface engineering issues, such as safe injection and injection pressure limitation, wellbore stability, fractured injection and stimulation, and completions optimization. In addition to these more ‘traditional’ field development decisions, in-situ stress has direct influence on the rapidly growing CCS industry, where storage volumes of CO2 are highly dependent on the initial minimum effective stress margins available in the sealing caprock(among other factors). In this work we investigate a unique in-house stress database, obtained through decades of dedicated stress testing, to better understand and quantify the relationship of in-situ stress versus depth and its relation to pore pressure. Focus is primarily on the Norwegian Continental Shelf but global results from additional passive continental margin areas are also incorporated and compared. We find that, almost regardless of the geographic area, when hydrostatic pore pressure conditionsapply, relatively simple linear relationships exist of stress versus depth and that the assumption of normally-stressed/relaxed stress regimes can be applied with a good degree of certainty. Further, where overpressure conditions are present, relationships dependent on the degree of overpressure are defined, both regionally and globally. The resulting overpressure relationship is found todiffer fromthose commonlyaccepted andused throughout industry, e.g. Breckels and van Eekelen 1982. Finally, the resulting stress trends versus depth are investigated to better identify the potential presence of high stress environments such as deeper strike-slip to reverse faulting regimes that can complicate field development decisions. While of interest to the hydrocarbon industry in general, the results of this work are highly valuable to under-explored areas where in-situ stress data is not yet available, e.g. saline aquifer prospects targeted for eventual CCS development.

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