A Novel Approach to Characterize Dynamic Interaction Between Super Permeability Layers with Vertical - Faults and Their Affect on Flood Front Movement

Abstract

Abstract Managing the Ghawar Field with super permeability layers and vertical faults, with a mission of maximizing oil recovery with the lowest cost, is a challenging task. Super permeability layers are associated with high productivity where the flow is confined to 10-20 feet layer in a 250 feet thick reservoir. After producing part of the reserves, 3-D seismic and horizontal drilling clearly indicate the existence of fault systems. Vertical faults can be connected to the super permeability layers in certain locations of the field. Pressure testing happens to be a powerful reservoir characterization tool when integrated with geological and geophysical data as well as specially designed horizontal wells. This paper describes the planning, execution and results of series of extensive field testing which were performed to understand reservoir large-scale flow features (faults or joints). Data integration has resulted in characterizing fluid movement to be governed primarily by systematic large scale flow features which are almost parallel to both flood- front movement and to the maximum horizontal stress direction. The horizontal isolated super permeability layers are a secondary source of water movement, since it is dynamically supported by the faulting system. Diagnostic tools were developed and implemented to address the issue of when can the super permeability be produced to advantage and when it should be avoided, by considering the dynamic interaction between the two systems. P. 737