A reliable sanding prediction is required for field development decisions including well construction and facility design and the overall field's economics assessments. This paper shows an example from a gas field in Western Australia at its early development stages. A field-specific 1D geomechanical model calibrated with field stress measurements and drilling data, well logs and core tests is used to assess the risk of sand production for field life duration for both existing and future wells. The field geomechanical model revealed subtle variations from the regional stress regime with significant implications for sanding tendency and sand management strategies. An initial evaluation using a non-calibrated stress model indicated low sanding risks. However, the revised study calibrated with well tests and productions indicated considerable sanding risks within first few years of production. The sanding risk and sand volume rate is expected to increase with further depletion potentially requiring well intervention for existing producers and active sand control for newly drilled and cased and perforated wells. The analysis also indicated negligible field life sanding risk for vertical and low-angle open hole wells. A combination of passive surface handling and downhole sand control methods are considered using the well-specific sanding risk as a guide. Existing producers are monitored for sand production using acoustic detectors and future wells will have sand catchers to ensure sand production is monitored, quantified, and managed. Vertical and low-angle wells with open hole completion with sand screens are being planned for the upcoming development campaign.
Sand production prediction is essential from the early stages of field development planning for completion design and later for production management. Unconsolidated and weakly consolidated sandstones are prone to fail at low flowing bottom hole pressures during hydrocarbon production. To predict the critical flowing bottom hole pressure for a safe (sand-free) drawdown, a geomechanical sanding model that integrates in-situ stresses, rock mechanical properties, well trajectory, reservoir pressure, production plan and depletion trend is required.
