This paper demonstrates how multiple diagnostics, when applied effectively, can help accelerate the learning curve in an area and optimize field development. The operator can obtain exceptional knowledge concerning which technologies to choose when targeting specific issues for future developments. The project involved a wine-rack of wells completed in Niobrara A, B, and C benches. Learning objectives for this project included the completions order, height growth in various benches, well spacing, well lateral landing, effect of varying treatment type and size, and cross-well communication. An extensive survey was performed of the various diagnostics available for fracture mapping, which included both near-wellbore (NWB) and far-field diagnostics. Keeping the primary learning objectives in mind, a project matrix was developed incorporating a variety of diagnostics focused on specific objectives. Inferred vs. direct measurement from diagnostics was considered. This process of "design of experiment" is discussed. The wells on the pad were all hydraulically fractured, and then the entire pad was moved to production phase post the hydraulic fracturing operations. Different fracturing fluids were also evaluated as part of the experiment. The final project included far-field diagnostics, such as downhole microseismic, downhole fracture height, surface microdeformation, and interferometric synthetic aperture radar (inSAR), and NWB diagnostics, such as permanently installed fiber optics and radioactive (RA) tracers. The analysis was performed on individual diagnostics independently, and subsequently combined interpretations led to better subsurface understanding. Additionally, surface microdeformation data provided significant insight into the effects of "zipper fracturing" and how the treatment order of the wells was important for optimization. With all data available, a fracture model history match on the permanent fiber optics well was constrained to the measured diagnostics. The final match between the aerial deformation from the surface tilt and calibrated fracture model was excellent and is discussed further. Understanding the actual hydraulic fracture geometry is important in any unconventional field development because it dictates the stimulated reservoir and drainage patterns. While understanding the effects of various parameters (treatment type, fluid type, stage lengths, number of perforation clusters, etc.) on fracture geometry is essential, it is also important to understand the effect of multiple wellbores on a well pad.

This paper demonstrates how a single permanent fiber installation allowed the development of improved completions designs in real time in order to improve well economics. Design changes were adjusted during the completion of the well to determine stage length and completion execution. Improvements were applied to the subsequent wells in the program. In 2018, an eight-well pad was completed with the intention of immediately drilling and completing a second directly offset eight-well pad. Further options for additional wells would be evaluated based on the performance of these sixteen wells. The laterals of the project wells were arranged in a wine-rack configuration targeting zones in the Upper and Lower Eagle Ford Formation. Initial designs were based on analytics from the area resulting in an initial design for cluster spacing, stages per cluster, injection rates and volumes, and fluid volumes. The primary goal of the diagnostics expenditure was to improve the dollars per barrel relationship, specifically by increasing stage lengths that could be effectively completed along the lateral wellbore. The project included a casing-installed fiber optic cable to record the distributed acoustics and distributed temperature along the wellbore for, respectively, stimulation flow profiles and production flow profiles. Acoustic-based flow profiles were generated during the project and evaluated to influence the next set of stage designs. These design changes involved among other variables adding clusters to the stage, sand staging, and rate adjustments, At the end of the project, completions changes resulted in a reduced individual well cost of 11%. Production profiling began to compare stage designs along the lateral and to confirm baseline well performance versus its peers. In both cases, those results confirmed that the design changes lowered the overall cost while maintaining well performance.

One of the latest developments in permanent fiber optics is ability to install and complete a well in rapidly based on the needs of the program. This paper will present the drivers leading into the operation, the data collected and the completion advances resulting from a permanent fiber conceived and executed in under four weeks. Completion changes were conceived following direct observations of distribution of flow rate, defined in a Uniformity Index. The resulting changes were cost neutral to the overall program but showed improved completion results and well performance.

Current hydraulic fracturing strategies require a significant investment of resources, time, and capital to warrant well productivity. As a result, it has become the crux of asset development in unconventional formations. Given that this technique has been in full force for almost two decades, the optimization strategies couldn't be more varied than they are today. Part of the problem exists in completion teams discretizing and optimizing individual facets while ignoring their impact on the entire system. To the authors’ knowledge, this paper is the first to present a comprehensive energy analysis of the hydraulic fracturing process. During hydraulic fracturing, energy transfer originates from the horsepower equipment used to inject a unit volume of fluid, containing a certain volume fraction of proppant, into the wellhead. Surface energy consumption is defined as the horsepower deployment integrated over time. As this unit volume traverses down the wellbore and into the formation, it is assisted by gravitational potential energy, which supplements its energy budget but must overcome the friction from the pipe, perforations, and tortuous near-wellbore zone, which act as energy losses. Subtracting energy losses from the total energy input results in the effective energy delivered to formation. With the tools outlined here to calculate the effective energy and energy efficiency, teams can vet and optimize their completion strategies to maximize energy delivered to the formation and/or improve capital efficiency. These metrics are sensitive to most of the variables involved in well completions and provide an understanding of the influence every decision has on the complete hydraulic fracturing system.

Historically, Great Western Petroleum has been an operator focused on efficiency without much focus on altering completion designs. Based on the successes of Extreme Limited Entry (XLE) in other basins, a science project was constructed to test different XLE in the first zipper group of a two-zipper group pad. The goal was to find a design that would yield the same production, but with less cost. Increasing stage length provides a significant cost saving and with XLE, production should be maintained. Based on the results from zipper one, the best design could then be implemented on the same pad in the second zipper group. This allows for a direct comparison of hydraulic fracturing designs, minimizing geologic impact. This study was comprised of a number of different datasets with the primary focus being on Distributed Acoustic Sensing (DAS) using wellbore fiber optic cable. DAS is a rapidly evolving technology with numerous advances in both function and cost over the last few years, especially in fiber optic cable deployment. An opportunity was seen to not just gather data, but to test the data quality of the latest deployment methods, specifically a pump-down dissolvable, single-use fiber optic cable. This is a cost effective and minimal footprint option for data collection. This project included three acquisition methods for the DAS: 1) a permanent fiber optic line cemented on the outside of the casing, 2) a wireline retrievable fiber optic line, and 3) a pump-down dissolvable single-use fiber, all deployed in three unique wellbores. The permanent fiber optic well was used to compare the uniformity index of different completion designs. The designs were altered based on the results from the previous stage until an optimal design was reached. This DAS acquisition also provided offset strain and microseismic in the first and second zipper groups. The wireline retrievable fiber optic cable and single-use fiber optic cable deployments provided offset strain and microseismic for the wells in the first zipper group. High level observations resulting from this project include: The data quality associated with the dissolvable single-use fiber looked comparable in data quality to the other fiber optic deployment methods.The Uniformity Index was high for most designs, even with stages as long as 450 ft and cluster spacing as tight as 7 ft.350’ stages with 14 clusters at 1 spf was chosen for the second zipper group wells This provided significant cost savings, along with high stage uniformityResults from the offset strain and microseismic analysis from tighter and more clusters per stage showed less interference than what was seen with our legacy design stagesRTA shows that compared to a pad with similar well spacing, the production is better with the new hydraulic fracture design Having a case study with various fiber optic deployments is rare. At the time of this deployment, this was the first pump down dissolvable single-use fiber optic line in North America. This paper will show the efficacy of this fiber optic deployment compared to its peers. It also will look at conventional and XLE designs and the well-to-well interference differences. Finally, being able to compare production results to an offset pad with the same well spacing provides a unique opportunity to validate the effect of a new hydraulic fracture design.