Self-channeling in proppant pack in the Eagle Ford Shale formation Conference Paper uri icon

abstract

  • Copyright 2017, Society of Petroleum Engineers. Well deliverability is directly related to the hydraulic fracture conductivity of the created fracture networks. There are several influencing factors on fracture conductivity, including fracture surface topography, mechanical properties, and proppant concentration. Fracture surface topography inherently defines the connectivity of cavities inside the fracture that serve as flow channels, and such flow channels are further enhanced by the presence of proppant. This paper presents a study considering the aforementioned phenomena, centered primarily on the effect of proppant concentration on the primary hydrocarbon-baring Unit B of the Eagle Ford Shale formation. Laboratory experiments were conducted to investigate the effect of proppant concentration on fracture conductivity for Eagle Ford Shale samples. The test samples were obtained from outcrops at Antonio Creek, Terrell County, Texas. A 100-mesh sand was utilized, as it is representative of the industry practice in the region. Fracture conductivity measurements were conducted by flowing dry nitrogen at varying closure stress stages. Ancillary measurements included Young's Modulus and Poisson's ratio obtained by a tri-axial compression test. The Brinell hardness number was measured by an indentation test, and fracture surface topography was obtained using a laser profilometer. Results show that the initial evenly distributed proppant concentrations were altered during the process of measuring fracture conductivity, yielding a final proppant distribution that partially occupied the fracture surface. The remaining surface area was absent of proppant and served as channels of high conductivity relative to the areas occupied by proppant. It is believed this behavior occurs in field operations, especially under conditions of varying gas flowrates during production. Additionally, this work suggests the possibility of an optimum initial proppant concentration that can result in the highest channeling behavior for a particular fracture surface.

author list (cited authors)

  • Guerra, J., Zhu, D., Chacon, J. U., & Castillo, E. L.

complete list of authors

  • Guerra, J||Zhu, D||Chacon, JU||Castillo, EL

publication date

  • January 2017