An appropriate propped fracture is important for oil and gas production (especially in shale formations). The actual proppant placement during fracturing is generally unknown. Any fair prediction of the placement of the proppant may results in significant improvements for the fracture protocol design. We present experimental data on the transport and settling of particles dragged by water through a narrow wedge-shaped vertical fracture. We discuss some basic features of the dynamics of the settlement of the proppant dune and show results on the final placement for different pumping rates and particle sizes. Results are consistent with previous findings by others and confirm that some usual practices in the field are beneficial to maximize the propped volume and minimize arching.
In recent years, many oil companies have directed their efforts towards developing unconventional reservoirs. The challenges encountered to guarantee a profitable operation in these plays lead the industry to devote significant amounts resources to optimize processes such as hydraulic fracturing, a vital stimulation technique.
Hydraulic fracturing consist in the injection of fluids, along with proppants, into the formation aimed at creating and/or enhancing existing fractures to open high conductivity channels connecting the formation and the wellbore .
Proppants are granular materials that fill the fracture and support the closing pressure, keeping the fracture conductive during production. Although fracturing techniques have evolved, there is still opportunities to increase efficiency. Many of these opportunities are related with the way in which proppants are transported and deposited into the fracture.