Optimization of Fracture geometry: A case study in the Oligocene formation, White Tiger field
Nguyen Huu Truong

Petrovietnam University

Abstract

Many hydraulic fracturing treatments have been carried out for producer wells selection with low permeable formation in the primeval sedimentary of the White Tiger field to increase the permeability of the reservoir and increase the fracture conductivity, leading to increase the productivity index. Several treatments recorded a higher fracture growth in comparison with the effective reservoir thickness, resulting in poor proppant distribution within the fractured reservoir, and shorter propped length, narrower propped width, resulting in poorer propped fracture conductivity. In this study, the optimally designed the optimal propped length and propped width using Unified fracture design (UFD) in combination with symmetrical fracture height evolution with a pseudo three-dimension model (p-3D) for three-layered formation under the constraint of maximum proppant distribution per unit fracture area created, or optimum dimensionless productivity index for the low permeability reservoir. Results for a single well production fracturing case in the upper Oligocene formation have been obtained, using such fracture height migration of 154.1 ft, pay zone thickness of 120 ft, propped fracture half-length of 343 ft, propped fracture width of 0.19 in, propped fracture conductivity of 790 mD.ft, the highest percentage of proppant placed in the pay at 77.87 % by 155,743 lbs of proppant size 16/30 of Sintered Ball Bauxite (SBB), propped mass used 200,000 lbs.

Keywords: Unified fracture design, equilibrium fracture height migration, insitu stress, treating pressure

Topic: Engineering of Drilling, Production, and production surface and facility