Fracturing treatments using treated water and very low proppant concentrations ("waterfracs") have proven to be surprisingly successful in the East Texas Cotton Valley sand. This paper presents field and production data from such treatments and compares them to conventional frac jobs. We also propose possible explanations for why this process works. Introduction Hydraulic fracturing is the key technology to develop tight oil and gas reservoirs. Although millions of research dollars have been spent to date, much controversy remains about optimizing fracture design. Rock mechanics and fluid transport phenomena in hydraulic fracturing are still poorly understood. The processes are very complex with a host of unknowns. Measuring even one critical value such as net fracture treating pressure constitutes a difficult problem. Hydraulic fracture research and development has put a lot of effort into effective placement of propping agents to provide and maintain fracture conductivity. For this purpose the service industry has developed sophisticated fracturing fluid systems and an extensive recipe of chemical additives. The fluid system is engineered to change viscosity during its journey from the surface to the fracture and afterwards during fracture cleanup. The sole reasons for these fluid designs is to place proppant, minimize formation damage and ensure proper cleanup. In turn, the proppant has no function other than maintaining a conductive fracture during well production. What would happen though if the fracture actually retains adequate conductivity with very little or no proppant?–Rock fractures often have rough surfaces. After the fracture closes, the residual aperture distribution can be very heterogeneous in all three dimensions forming a very conductive path even at high closure stresses. - Proppant along with gel residue could actually impair fracture permeability and its ability to cleanup.–Fracture extension and cleanup is easier to achieve with low viscosity fluids. Fracture extension is the key design parameter in tight reservoirs. The above points may have a tremendous impact on the fracturing operation. Gelling agents, proppant and associated chemical additives comprise a large part of fracturing costs. In early literature, "self-propping" and "partial monolayers" of fractures has been discussed. In general though, the industry has discarded the idea. In the naturally fractured Austin Chalk the so-called "waterfrac treatments" are pumped with no propping agents. They are very successful. Why it works is still generally unknown. The hydromechanical response of natural fractures has been addressed in rock mechanics literature. It is an extremely important issue in the field of underground nuclear waste disposal. The effect of normal stress and shear stresses on a fracture (natural and artificial) dictate its conductivity. The ramifications of these forces on fracture propagation are just now beginning to be investigated (multiple fractures). Description of "Waterfracs" The following outlines the general pumping schedule (from here on, the treatments will be referred to as "waterfracs"). P. 457

Pillars of the Industry - How knowledge management enhances technical training programs. World demand for oil is at an all-time high, and the oil industry is riding one of its busiest cycles in history. This creates a wonderful market in which current college graduates and young professionals can get involved. Positions are open across the industry for almost any type of technical degree. While this is great for the young professionals of the world, it creates many challenges for the industry. Issues arise regarding how to train and mentor these new employees as they progress into productive positions as quickly as possible. If it isn't enough to provide training on oilfield practices and technology; we are also facing what many in the industry are referring to as "the great crew change." In the next 5–10 years, a large majority of employees who hired on in the boom of the 1970s and early 1980s will be retiring. These employees are commonly referred to as the "knowledge base" for the industry. This means that in addition to training young professionals on general oilfield material, we must also pass along or otherwise retain as much of this knowledge as possible. Halliburton has taken a somewhat blended approach to this problem involving a tailored Technical Training Program (TTP) and what we refer to as Knowledge Management (KM) communities for collaborating on and cataloging solutions to issues. This article will address each one of these separately to point out their unique benefits, but also explain how they complement each other to create a complete training and development environment. First look at the TTP.