Modeling Horizontal-Completion Deformations in a Deepwater Unconsolidated-Sand Reservoir

Abstract

Summary We present the development and results of geomechanical models and analyses used to assess the risks of compaction-induced deformation and potential failure of horizontal gravel-pack completions in a field located in deep water but at shallow depth below the seafloor. The target reservoir consisted of high-porosity, underconsolidated stacked turbidite sandstones, which are comparable to some of the more well-known, problematic compactive reservoir sands. The formations indicated a high level of risk of depletion- induced compaction, which could produce large deformations and potential failure of completion equipment in horizontal wells. Coupled poroelastoplastic geomechanical finite-element models were constructed to assess the risks of completion-equipment damage because of depletion-induced reservoir compaction. Both openhole and cased-hole gravel-packed completion configurations were analyzed. Details of the prepacked-screen assembly components were included in the models, such as the ribs between the base pipe and inner screen and the deformable epoxied sand between inner and outer screens. Model results presented in this paper include deformations of the completion equipment and stresses in the screen components, as a function of reservoir-depletion pressure. The results of the geomechanical modeling indicated that the overall compaction loading should not cause significant deformation of the specified completion equipment.

Geomechanics Coupled Fluid Flow in Heavy Oil Reservoirs Considering Cold Production

“…Hilbert, L. et al (2011) [7] presented the development and results of geomechanical models, and also the analysis used to assess the risks in an unconsolidated reservoir located in deep water. The formations had a high risk of compaction induced by depletion, which could produce large deformations and potential failure of completion in horizontal wells.…”

Numerical Analysis on the 3D Mechanical Behavior of Completion Tubing under Subsidence Loading

“…Shen (2010) reported his work on numerical modeling and analysis to subsidence prediction and casing integrity induced by pore pressure depletion. Hilbert et al (2011) introduced their works on geomechanical modeling and analysis used to assess the risk of compaction-induced deformation and the potential failure of horizontal gravel pack completion in a field that is located in deep water but at a shallow depth below the seafloor.…”

Simulation and Visualization of Near-Well Flow

“…Particularly for long horizontal wells in loosely consolidated sands, the design of sand control completions has to strike the best trade-off between maximizing the protection against sand production and minimizing the impact on productivity, both initially and through the life of production. While optimization of this technology either by laboratory studies or through computational simulations has been the subject of many studies over the last decades (Gurley et al, 1977) and is still actively investigated today (Becker and Gardiner, 2000;Blok et al, 2000;Hilbert et al, 2011;Jain et al, 2011;Martins et al, 2005;Navaira et al, 2009;Neal, 1983;Oyeneyin, 1987;Suri and Sharma, 2010), the current design of screens and supporting tubing (basepipe) in a sand control completion are based on empirical pressure drop correlations that are developed for the individual elements, but not for the entire sand control assembly. Yet, the complexity of the geometry (illustrated in Figure 1 for a gravel pack completion) implies the complexity of the flow whereas the total pressure drop from the formation to the well is, in general, different from the sum of the individual components.…”