This Presentation Will:
1. Introduce a new way of evaluating reservoir uncertainty with RESASSURE
2. Illustrate the concepts used
3. Highlight the benefits achieved
4. Demonstrate the value of the results
Stochastic Simulation has unleashed the world’s fastest reservoir simulator, ResAssure, which is set to revolutionize production planning and reserves reporting in the Oil & Gas industry.
ResAssure easily computes > 1 Million realisations within a 24 hour period, a fraction of the time it currently takes with traditional methods and software packages. The release of ResAssure marks a significant milestone in the history of reservoir simulation – the first real industry technology advance in 30 years.
Dr Wadsley, Chief Technology Officer at Stochastic Simulation, commented “ResAssure is capable of quickly generating more accurate reserve estimates than is currently possible by any other software system. The approach taken generates a complete distribution of history matched models all of which are consistent with the geological model and observed production history. The time taken for this is orders of magnitude faster than current history matching methods.”
“Field development planning based on ResAssure’s distribution of models (rather than just upon a single history-matched model using conventional methodologies) will significantly reduce uncertainty and risk.” he added.
By enabling faster and more accurate analysis of dynamic subsurface geological data than has previously been possible, ResAssure markedly reduces the risk in the development of oil and gas fields by narrowing the range of uncertainty in reserves estimates: thereby supporting better production and financing decisions, with substantial increases in project ROI.
ResAssure’s innovation in reservoir simulation solves fully-implicit, dynamic three-phase fluid flow equations for every geological realisation. The speed breakthrough was achieved by a combination of proprietary algorithms, polygonal gridding and aggressive spatial coarsening and time stepping, based upon a conventional finite-difference discretization of the reservoir.
Key Insights Identified:
1. Consistency between volumetric, material balance and fractional flow places very strong constraints on feasible reservoir models.
2. The mathematics of reservoir simulation is NOT complex – it is the geology which is complex.
3. Reserves uncertainty is not quantified, but estimated from current ‘best’ estimate in an ad hoc unsystematic way.
4. What’s the point of preserving mass balance in the simulator when the hydrocarbons in the reservoir are imprecise and we don’t include all production data – mass balance should act to regularise our solution, not to define it.
5. The role of reservoir simulation is not to compute an exact solution of a poorly defined geological model – it is to define a range of feasible reservoir models and associated production forecasts.