Review of Survey activities 2014: Down-hole permeability prediction – a chemometric wire-line log feasibility study from a North Sea chalk well

Permeability in chalk depends primarily on porosity but also on other factors such as clay and quartz content, and can theoretically be described by the Kozeny equation using empirically determined constants (Mortensen et al. 1998; Røgen & Fabricius 2002). Recent attempts to predict permeability from wire-line logs have shown that compressional velocity within operative chalk units, defined by specific surface and hydraulic properties established from stratigraphy and core plugs, can provide excellent well permeability predictions (Alam et al. 2011). High-quality predictions depend on a solid knowledge of a multitude of parameters of the relevant ‘operative rock types’. The more detailed this a priori knowledge is, the better predictions can be achieved. But this approach may, or may not, be fast enough for wellsite operations or when core data are lacking. In this study, we illustrate a situation for direct permeability prediction if only well-site, wire-line logs are available

European Unconventional Oil and Gas Assessment (EUOGA) - Development and application of a unified methodology

Over the last decade, various international and national assessments of shale gas and shale oil resources for most EU-countries have been published. Due to methodological differences and in fundamental assumptions related to the quality and quantity of underlying geological information, these results are not comparable and in some cases not reproducible. This presentation focusses on the development and definition of a uniform methodology for estimating (in-place) shale gas and shale oil resources at the pan-European level within the context of the EUOGA study (EU Unconventional Oil and Gas Assessment). The presented methodology is established to determine estimates of GIIP (Gas Initially In Place) and OIIP (Oil Initially In Place) including associated uncertainty bandwidths originating from the various geological input parameters. The method is applied to 81 onshore shale gas or oil formations from 33 thermogenic and two biogenic basins located within the participating European countries. The results of the assessment include a geological description of the basins together with a general chance of success, a ranking of the individual assessment units and the final calculation of GIIP or OIIP for the formations. Saudi Aramco; Shell; Tota