The Application of Unstructured Gridding Techniques for Full Field Simulation of a Giant Carbonate Reservoir Developed With Long Horizontal Wells

This paper presents a case history on reservoir simulation<br>modelling of a giant, complex, low permeability, carbonate<br>reservoir which has been completed with many long<br>horizontal wells. The lateral magnitude of the Al Shaheen<br>field in Qatar and the multiple radial layout of the 75 very<br>long horizontal wells in the field posed a challenge in<br>modelling of individual well performance using a manageable<br>grid size with an acceptable run time for history matching. The<br>gridding dilemma was solved by use of 2.5-D PEBI grids<br>around each individual wellbore. This allowed for sufficient<br>resolution between wells and also aligned the grid with the<br>well paths thereby avoiding grid non-orthogonality issues.