A One Dimensional Stochastic Inversion method that produces high quality reservoir property estimates with associated uncertainties, developed jointly by BP and Cegal.
Blueback ODiSI is a unique seismic inversion method that specifically includes only the most robust prior information in order to apply additional constraints to the solution.
Blueback ODiSI does not require any prior lateral constraints: the algorithm converges so that each trace can be inverted independently of its neighbors yet laterally continuity is still achieved.
The technology was originally developed by BP (Connolly & Hughes, 2013, 2014, 2016) while a Petrel version has been developed jointly by Cegal and BP.
The solution is robust yet logical and comes fully integrated into Petrel, complementing Cegal’s Quantitative Interpretation solution Blueback Rocks QI.
Dynamically QC the rock physics parameterization in Blueback ODiSI.
QC the bed thicknesses and transitions statistics to ensure the desired range of values is correct for each macro-layer.
Blueback ODiSI Inversion QC - allows the inversion to be QC'd at a selected individual trace location, and can also create virtual seismic cubes, so the inversion can be QC'd along selected inlines, crosslines and random lines.
Blueback ODiSI Inversion QC. These QC tracks display selected inverted properties for all the best match pseudo-wells.
Pseudo-wells (stochastic simulations of 1D stratigraphic profiles) with physical properties, are generated. Synthetics, derived from the pseudo-wells using EEI are then matched to the appropriate seismic angle stacks. The best matches are selected and averaged to provide a joint estimate of facies, reservoir properties, impedances and uncertainties.
Cegal is delighted to showcase the result of an ODiSI study conducted on a central North Sea field. The reservoir is an Upper Jurassic Fulmar interpod (depocentre) and is flanked by Triassic Smith Bank shale pods. Underlain by Triassic shales and Zechstein evaporites and overlain by Cretaceous lithologies, the field provides a challenge for seismic analysis, particularly inversion and quantitative interpretation.
Cegal would like to thank Repsol Sinopec Resources UK Limited for their support and engagement to undertake the ODiSI Inversion and their partners for their agreement and support to publish the case study.