Max N.

Unconventional plays in the US continue to be the biggest experiment in the history of the oil and gas industry. Particularly in the current market conditions of volatile oil prices, operators continue to introduce methods to maximize the efficiency of their operations. We examined the methods of adopting an aggressive approach to optimizing stimulation design to lower the breakeven level of operations and evaluated the results.

Public data were deciphered in a way they could be… Show more

Unconventional plays in the US continue to be the biggest experiment in the history of the oil and gas industry. Particularly in the current market conditions of volatile oil prices, operators continue to introduce methods to maximize the efficiency of their operations. We examined the methods of adopting an aggressive approach to optimizing stimulation design to lower the breakeven level of operations and evaluated the results.

Public data were deciphered in a way they could be interpreted to the level of granularity sufficient to conclude an effect of certain fracturing techniques of different operators and to compare on a similar scale measures that had been taken to improve fracturing design. Various analytical and statistical tools were employed to handle the large amount of data in both unaltered and normalized ways to demonstrate the trends in different US basins.

Operators made significant improvement in production by changing parameters in the fracturing and completion design strategy, including, but not limited to, the amount of water used, the amount of sand pumped, stage spacing, maximum sand concentration, and fracturing fluid selection. However, the challenge remains of determining whether the design is indeed optimum. This paper addresses the importance of aggressive design, its evolution, and enablement technologies. Show less

A new method of nonintrusive fracturing process monitoring in real time has been developed. The method is a combination of advanced signal processing algorithms and a tube wave velocity model based on Bayesian statistics and, thus, does not require complex hardware. This enables cost-effective and timely decisions at the wellsite. The technique was validated in the field in several fracturing and refracturing jobs.

Water production is a major concern for oil companies because it involves not only a high cost for handling the water on surface, but also issues related to scale and corrosion in tubulars, and an overall decrease of hydrocarbon production. Finding the right solutions for each case is a challenge because there is no one solution that fits all. Chemical treatments for water shutoff are cheaper than mechanical treatments and can offer more targeted and customized design, but they often come with… Show more

Water production is a major concern for oil companies because it involves not only a high cost for handling the water on surface, but also issues related to scale and corrosion in tubulars, and an overall decrease of hydrocarbon production. Finding the right solutions for each case is a challenge because there is no one solution that fits all. Chemical treatments for water shutoff are cheaper than mechanical treatments and can offer more targeted and customized design, but they often come with higher operational risks.

A new water control system based on a single particulate additive was extensively evaluated under laboratory conditions and then successfully implemented in the field. The fluid is easy to prepare using traditional field mixers and does not need curing after it is pumped into the formation, thus saving time and cost compared to most conventional water shutoff systems. The fluid was evaluated in the laboratory with a wide range of formation permeabilities and injection conditions using the fluid loss apparatus, permeameter, and formation response tester. The viscosity and stability of the fluid in different water salinity and concentrations were also investigated.

Overall, it was found that the new fluid system was very efficient in shutting-off formations greater than 50 md up to a few darcies. Those results were consistent with the nature of the plugging mechanism, which relies on physical pore plugging alone. The system could be further tuned depending on the formation permeability. In the presence of oil saturation, the penetration of the particulate system was found limited as compared to a single-phase, water-saturated core. Show less

SPE-189540-MS

With an ever-increasing number of horizontal wells and stimulation stages, only 30 to 40% of stimulated clusters are contributing to production. Most of the methods that can confirm the cluster stimulation either requires additional well intervention operations or has a large footprint. Additionally, interpretation by the skilled professionals make such methods purely post-job: nothing can be done to correct under or over-stimulated set of clusters.

Because of that, most of the decisions… Show more

With an ever-increasing number of horizontal wells and stimulation stages, only 30 to 40% of stimulated clusters are contributing to production. Most of the methods that can confirm the cluster stimulation either requires additional well intervention operations or has a large footprint. Additionally, interpretation by the skilled professionals make such methods purely post-job: nothing can be done to correct under or over-stimulated set of clusters.

Because of that, most of the decisions on the well site, during stimulation process is made using surface pressure data. Changes in pressure values, slope and shape, are used to justify changes in the job design.

In this study, we comparison of the traditional pressure- based decision making and new high-frequency pressure analysis method. Three wells will be presented, demonstrating such common events as ball landing confirmation, diverter effectiveness confirmation, ball failure during treatment and detection and location of casing leak. This technique allows the operator to make informed near -real-time decisions. Show less

The development of unconventional fields has experienced major efficiency gains. One main breakthrough in efficiency is the introduction of viscous slickwater fracturing fluids. Viscous slickwater enables placement of higher proppant concentration than conventional slickwater and is less damaging than guar-based fluid, leading to aggressive fracturing designs and improved production.

High viscosity friction reducer is the main component in viscous slickwater, which can replace hybrid and… Show more

The development of unconventional fields has experienced major efficiency gains. One main breakthrough in efficiency is the introduction of viscous slickwater fracturing fluids. Viscous slickwater enables placement of higher proppant concentration than conventional slickwater and is less damaging than guar-based fluid, leading to aggressive fracturing designs and improved production.

High viscosity friction reducer is the main component in viscous slickwater, which can replace hybrid and crosslinked fracturing fluids in unconventional reservoir completions. The successful application of high viscosity friction reducing fluid requires proper fluid hydration and adequate viscosity, which depends on water salinity and proppant concentration. We developed techniques for improved testing of friction reducers and friction reducer selection guidelines to support optimum placement of the fracturing design. A comparison of production results of wells fractured by viscous slickwater to those offset wells demonstrated the effectiveness of aggressive design with viscous slickwater fluids.

A high viscosity friction reducer was tested in the laboratory and applied in the field. Experimental data demonstrate a good correlation between low shear viscosity and proppant transport capability. Static and dynamic proppant transport data were used to design viscous slickwater to replace linear gel. The friction reducer has been successfully applied in the field in more than 3,000 stages. Formations that were traditionally fractured with crosslinked gel were successfully fractured using viscous slickwater with ease. Replacing conventional slickwater with viscous slickwater enables the transport of higher proppant concentration with little change in operations. Aggressive designs deliver a boost in production, thus confirming viscous slickwater as the fluid of choice.

Show less