Fracture Measurement and Control (cluster 16 - consequence)
Early efforts to use fracturing technology encountered many difficulties, as the technique was not well understood. As early as 1986, natural gas companies were experimenting with hydraulic fracturing in traditional, vertically-drilled wells. However, these early efforts were plagued with problems. Incomplete models and insufficient planning led to wells which did not perform as expected, showing a need for further research into the topic of fracture pattern modeling. Research to improve these fields was necessary.
A paper by Bennett (1986) addresses the issue of fracture size, and how it changes in response to the various propping agents and pumping techniques. Bennett highlights an issue in which uncontrolled fractures extend out of the shale rock formation, affecting the more porous rock around the well. Other papers on this issue address similar themes, offering field data and models to use when trying to control the fractures and extent of the fractured well. (Crump, 1988) The most recent paper in the cluster was published in 1993 (Desroches) which contests a common type of fracture-pattern model used when planning wells. These common models assume a pattern of radial symmetry, but do not account for a number of factors which affect potential fracture patterns. Desroches suggests a new model which incorporates several of these previously unaccounted-for factors. Altogether, this cluster of research concentrates on the control and prediction of fracture patterns in rock, a topic which is vital to the development of hydraulic fracturing as a technology.
Significant papers
- Bennett, C., Reynolds, A., Raghaven R., and Elbel, J. (1986). Performance of finite-conductivity, vertically fractured wells in single-layer reservoirs. Society of Petroleum Engineers Formation Evaluation, 1, 399-412.
- Crump, J. and Conway, M. (1988). Effects of perforation-entry friction on bottomhole treating analysis. Journal of Petroleum Technology, 40, 1041-1048.
- Desroches, J and Thiercelin, M. (1993). Modelling the propagation and closure of micro-hydraulic fractures. International Journal of Rock Mechanics and Mining Sciences & Geomechanics Abstracts, 30, 1231-1234.