bluuebunny/crossref_metadata_2025_split huggingface dataset:
Constraining the Complexity of Stimulated Reservoir Volume during Multi-Stage Hydraulic Fracturing of Horizontal Wells through Inter-Well Pressure Hit Modeling
Authors: Shokri A. Rangriz , Chalaturnyk R. J. , Bearinger D. , Virues C. , Lehmann J. 
Published: October 2017

Abstract
To determine the degree of connectivity and complexity of a stimulated fracture network, a prescriptive completion program was undertaken in the Horn River Shale Basin which enabled continuous monitoring of pressure interactions among horizontal wells during multi-stage hydraulic fracturing. This paper introduces a novel approach to characterize the stimulated fracture network, and consequently, to optimize the stimulation, wellbore placement, and re-fracturing designs, by integrating the pressure hits captured from passive wellbores on a pad during fracturing operations. If effective, it may also provide a cost-effective alternative to microseismic monitoring.
The workflow initially considers a rigorous data analysis on available pressure hits at each frac-stage in time and space, including the location of pressure events, time of flights to offsetting stimulation, and the magnitude and intensity of pressure hits/falloffs. Streamline simulation, assisted with a hydraulic fracturing module, is then used to match the pressure hits/falloffs in the passive wells. This ultimately provides a dynamic probabilistic 3D map of the fracture network growth, reservoir complexity and inter-well connectivity. The fundamental mechanisms of hydraulic fracturing and the interactions across natural and induced fractures (fracture initiation/propagation/growth) are implemented by means of an advanced coupled hydro-mechanical code, based on distinct element method.
Results from initial data analyses were fed into a hydro-mechanical model, which incorporated the physics of the hydraulic fracturing process, in order to reproduce the pressure hit signatures. An assisted streamline-based technique was used to simulate various scenarios of pressure hit responses to construct a database of standard pressure hit/falloff patterns. This database, compiled into a dynamic 3D map, facilitated a probabilistic approach to calculate a robust estimate range of stimulated fracture network of the pad area. This database can be subsequently used in future stimulation and re-fracturing designs. The backbone of the highly complex fracture network, extracted from pressure hit/falloff data, was found to closely align with high-resolution microseismic data.
Calibration of the hydro-mechanical model using the pressure hit data provides increased confidence in the use of the model to optimize well placement and hydraulic fracturing designs. In the absence of microseismic data, this unique workflow has the potential to deliver real-time on-site monitoring of fracturing operation at a reduced cost and acceptable accuracy, to provide additional statistics on complexity of stimulated reservoir volume, and to offer a better assessment of the likely range of the induced fracture network among horizontal wells.
New Model for DFIT Fracture Injection and Falloff Pressure Match
Authors: Liu G. , Ehlig-Economides C. 
Published: October 2017

Abstract
Analysts regard the fracture injection and falloff test known as the diagnostic fracture injection test (DFIT) as a reliable tool to quantify formation closure stress, leakoff coefficient, formation permeability, and pressure. The recent analytical DFIT model for before and after closure enables matching the pressure falloff for abnormal leakoff behaviors, and quantification of many more formation parameters than traditional DFIT models. However, the model design addressed only the falloff data after shut-in, and many express concerns that net pressure implied by the falloff is inconsistent with the injection pressure behavior. This paper provides a model capable of matching both injection and falloff pressure behavior.
The pressure falloff model is capable of quantifying essential pressure values including, in order of occurrence, instantaneous shut-in pressure (ISIP), minimum fracture propagation pressure, one or more closure stress values, minimum stress, and pore pressure. The early pressure response represents the dissipation of three kinds of friction, wellbore, perforation, and near-wellbore friction, each of which are quantified, and which together comprise the difference between the pressure at the end of injection and the ISIP. Presence of tip extension enables quantification of the minimum fracture propagation pressure. The minimum stress is consistent with the final closure stress. Subtracting the closure pressure and friction pressure losses from the recorded or calculated bottomhole pressure provides the fracture net pressure. The model match for injection pressure behavior incorporates the same pressures and consistent values for 2D fracture geometry and leakoff coefficient.
The global match confirms not only the estimation of formation and fracture properties from the pressure falloff analysis, but also the pressure distribution along the wellbore, through the perforations and the near wellbore, and in the fracture during and after injection. In particular, by matching both injection and falloff, the model incorporates friction pressure losses that can explain apparent excessive net pressure.
The match with both injection and falloff pressure variation addresses concerns that the net pressure implied by the falloff model match cannot be consistent with observed injection behavior. When the pressure difference between the final DFIT pick for closure stress and the pressure at the end of injection is very large, the reason may be large friction pressure losses and/or tip extension. Design for the main fracture treatments could consider an altered perforation strategy to reduce friction losses and/or reduce cluster spacing to address very low effective permeability likely consistent with tip extension and confirmed by the after closure match.
Frac Hit Induced Production Losses: Evaluating Root Causes, Damage Location, Possible Prevention Methods and Success of Remedial Treatments
Authors: King George E. , Rainbolt Michael F. , Swanson Cory 
Published: October 2017

Abstract
Frac hits or "frac bashing" is a fracture-initiated well-to-well communication event that can create production losses (or gains), and on occasion, mechanical damage when frac energy from a stimulated well extends into the drainage area or directly contacts an adjacent or offset well. Pressure increases have been detected in wells at distances ranging from hundreds to thousands of feet from the stimulated well. While these in-zone frac hit events do not pose an environmental problem if there is no failure of containment, there can be some alteration of the production potential in one or both of the wells involved.
Frac hits along the preferential fracture plane were an uncommon but known event when the completion method only involved vertical wells, but the rate of incidence has increased sharply as the preferred completion method has shifted to relatively closely-spaced, multiple fractured horizontal wells (MFHW) in low permeability formations such as the mudstone rocks commonly referred to as shales.
Mechanical damage within the well and success of methods of prevention, damage control and remediation will be examined by case histories and published contexts of incidents in several basins, but will not be the main goal of the paper.
The primary effort will focus on examining causes of production loss and duration of the loss, including looking at production declines pre-hit and post-hit. Known causes include in-situ stress alteration potential, timing of fracture closure, near-wellbore proppant loss, liquid loading, rock-fluid interactions, sludges and wetting factors. Also considered will be geological effects such as regional fractures and linked natural fracture clusters. A main objective will be to identify pressure transient, chemical analysis or other monitoring techniques to identify location and type of damage.
Remedial operations are most effective when the potential cause of production losses can be ranked probabilistically and the depth of the production-reducing event can be estimated as near-field or far-field. Analyzing this data will also assist in defining whether chemical or mechanical treatments such as refracturing or a hybrid treatment system may be the best approach.
Horizontal Water Injection to Sustain Production in a Low Oil Price Environment
Authors: Pettengell Katherine , Hascakir Berna 
Published: October 2017

Abstract
Over the past year and a half, the price of oil has plummeted from over $100 US per bbl in early 2014 to less than $47 US per bbl in the mid of 2017. In an attempt to sustain production without incurring significant additional expenditures, some operators may choose to implement enhanced oil recovery projects (such as waterflooding) while also utilizing existing infrastructure in the field. This paper focuses on one method of doing this by converting watered out or poor-performing horizontal production wells into horizontal water injection wells. The goal of this study was to create a screening criteria list which will enable assessment of a field to see if it could benefit from horizontal injection by way of converted horizontal production wells.
The study began with a literature search to determine if a similar study had been conducted previously. When the study was found to be unique, the literature search then focused on understanding the background of horizontal water injection, along with case studies to see which conditions led to success or poor performance of horizontal water injection schemes. The applications, optimization techniques, evaluation methods and challenges involved in conversion of horizontal production wells to injectors and the horizontal injection process itself have been summarized and compiled into a screening criteria chart which can be broadly applied to any field to see if it is suitable for the proposed application. The screening process works by assigning zero, one, or two points to the response to a number of criteria regarding the reservoir, fluids, wells, and other information. A higher point value indicates a higher likelihood of a positive outcome if a horizontal production well is converted to a water injector.
Emerging Leaders Alliance - The Application of Salient Learnings In Corporate Organizations
Authors: Pradhan Y. , Sturrock A. , Kotenev M. , Nunoo N. 
Published: October 2017

Abstract
The Society of Petroleum Engineers has actively participated in the Emerging Leaders Alliance (ELA) for 9 years since its inception in 2008. Through a stipend obtained from the SPE International Young Member Programs Budget, 86 young members have had the opportunity to attend the multiple day ELA. Attendees of the ELA are primarily early career leaders with management potential from the nine partner societies. Though topics stay relevant through a continuous improvement process, this paper will specifically address three topics from the 2016 ELA which were deemed most relevant to the authors: Performance Management, Emotional Quotient (EQ), and Technical to Managerial Transitions. The paper will discuss the significance, development and proposed protocol of performance management, whether if professionals are in the conducting or receiving end. The paper will also cover the roles of emotional quotient, or EQ, across technical and managerial positions for professionals of all levels of experience. Finally, the paper will cover when industry professionals should consider the transition from technical to management if they are interested. Interviewees included in the paper discuss how prioritizing these topics set themselves for successful careers. The interviewees will span a wide range of experience levels to display the relevance and application of the chosen topics despite one's career path. Young professionals should consider the three topics emphasized in the paper, as these are commonly overlooked or not prioritized. Proactiveness as early as possible on the topics discussed in this paper could increase professionals' chances of having a successful career. Professionals should also recognize that leaders and whom they supervise hold equal accountability to make the applications of performance management, emotional quotient and the technical to management transition conducive to the workplace.
Electronic Sliding Sleeve for Unlimited Zone Multistage Completion System
Authors: Merron Matt , Walton Zachary , Fripp Michael 
Published: October 2017

Abstract
A new electronic sliding sleeve was developed for hydraulic fracturing that combines the best features of traditional sliding sleeves and plug-and-perf techniques. The electronic sliding sleeve combines the operational efficiency of sliding sleeves with the potential to perforate unlimited zones inherent to plug-and-perf operations. This tool helps improve the efficiency of multistage fracturing sleeve completions by enabling more zones to be perforated and therefore more of the formation to be fractured.
Traditional sliding sleeves use a series of progressivelysized fracturing balls that shift sleeves along with progressivelysized baffles. The number of zones is limited by the strength of the fracturing ball and the interference between the ball and the baffle. Traditional sliding sleeves, however, offer an operational efficiency advantage compared to traditional plug-and-perf fracturing techniques. The electronic sliding sleeve is of monobore construction, which helps eliminate pumping restrictions through a series of progressivelysized baffles. An electronic sliding sleeve helps eliminate the mechanical complexity of other monobore fracturing tools and enables access to an unlimited number of zones.
The electronic sliding sleeve operates by counting the passage of fracturing balls through the tool and then shifting the sleeve when the programmed number of balls has passed. The electronic sliding sleeve has an on-board sensor and processor equipped to count the fracturing balls. Once the programmed number of fracturing balls has been detected, an actuator releases stored energy to enable the sleeve to shift. The key to the electronic sliding sleeve is a newly developed electrohydraulic lock, which stores the actuation energy. The electronic assembly increases the reliability of the sliding sleeve because the key components of the tool are embedded within the casing string and are not subject to proppant erosion or becoming caught on proppant trapped within mechanical parts. The electronic sliding sleeves can be used in the stimulation of vertical, horizontal, and extended reach wellbores.
A newly developed electronic sliding sleeve presents a new method for performing multistage hydraulic fracturing and is especially applicable in extended reach applications by offering an unlimited number of zones with a simple monobore construction. The programmable electronics help enable increased flexibility, reliability, mechanical simplicity, and robustness.
API RP 67 Recommended Practice for Oilfield Explosives Safety: Development of Proposed Changes to the Third Edition
Authors: Ayre David , Barker James 
Published: October 2017

Abstract
API RP 67 (1994) provided the industry with a common set of explosive safe practices. The last significant update was the second edition (API RP 67 2007). Since that time, the industry has undergone major advances in conveyance methods, technology, and processes. Additionally, in the post-9/11 era, security has been and is still being increased.
During the last five years, a dedicated group of more than 120 industry professionals has attempted to update and improve the recommended practice (RP) to enhancesafety for all individuals involved with oilfield explosive materials. Industry dialog has been fostered through discussions during perforating safety forums and industry safety and technology tradeshows.
The proposed new changes for the third edition of API RP 67 include the following:
Segregation of initiators into safety categories. Consideration of slickline, tractor, and coil tubing conveyance methods, in addition to the standard electric line (e-line) and tubing conveyed perforating (TCP) conveyance methods. Thermal management of explosives, particularly with consideration of HMX temperature overexposure and thermal runaway events. Safer use of pressure equipment with explosives. Improved security, audits, and personnel training. A fuller review of wellsite hazards associated with perforating.
At the time of this writing, the third edition is in the final stages of review, with publication expected in late 2017. This paper discusses these proposed changes and the reasoning for their inclusion in the third revision of API RP 67.
Multicolor Fluorescent Silica Nanoparticles as Tracers for Production and Well Monitoring
Authors: Murugesan Sankaran , Suresh Radhika , Kuznetsov Oleksandr , Khabashesku Valery N. , Darugar Qusai 
Published: October 2017

Abstract
Tracers play an important role in the oil and gas industry by providing valuable information about reservoirs. In particular, tracers can help in mapping water movementfor determining information on water flooding that can be used to improve hydrocarbon recovery efforts. Some of the challenges associated with current chemical or dye-based tracer technology are thermal degradation over time, phase separation, and tedious detection processes. To overcome these drawbacks environmentally friendly, multicolor silica nanoparticles as tracershavebeen proposed toprovide simpler and faster detection through fluorescence spectroscopy.
Designing Low-ECD Drilling Fluids for Superior Hydraulics and Sag Performance: A Rheological Approach
Authors: Kulkarni Sandeep D. , Williams Robert , Livanec Philip W. , Jamison Dale E. , Kohlt Timo F. 
Published: October 2017

Abstract
Typical organophilic clay-free invert-emulsion fluids (IEFs) are known to offer improved performance compared to conventional organophilic clay-based IEFs. However, for both the typical clay-free IEFs and conventional clay-based IEFs, high-temperature stability continues to remain a challenge from aequivalent circulating density (ECD) management and cuttings transport standpoint. This paper discusses the latest generation of clay-free IEFs, termed as "low-ECD clay-free IEFs,"that consist of specific combinations of weighting agents, colloidal particles, and polymers. The composition of these low-ECD fluids leads to different rheological behavior compared to typical clay-free IEFs, especially at high temperatures (&gt;200°F). This paper demonstrates that the peculiar rheological behavior of the low-ECD clay-free IEFs results in superior hydraulics and sag performance. Understanding the rheology also helps effectively design these fluids.
Experiments were conducted to study the rheology of several low-ECD and typical clay-free IEFs at high-pressure/high-temperature (HP/HT) conditions using rotational viscometers. Fluids were studied across a temperature range of 40 to350°F and up to 12,000-psi pressure. The data were used to develop models for predicting the rheology of various fluids as a function of temperature and pressure. Using the rheological models, hydraulics performance of the low-ECD and typical clay-free IEFs was simulated in a high-temperature well. The simulations evaluatedthe ECD and cuttings carrying capacity of these fluids. Sag behavior of the fluids in the well was also investigated.
The rheological study showed that typical clay-free IEFs thin with temperature (i.e., viscosity decreases with increasing temperature). In contrast, the low-ECD clay-free IEFs showed increased viscosity with temperature (i.e., temperature thickening). Temperature thickening was especially prominent at lower viscometer rotational speeds (i.e., lower shear rates). The temperature thickening helps the fluid retain its ability to suspend cuttings, barite, and other particulates. The contrast in the rheology behavior was used to demonstrate the ultimate advantage of the low-ECD clay-free IEFs—the desired cuttings transport and sag performance in a well can be achieved at significantly lower wellbore pressures (or lower ECDs) compared to typical fluids. Wellbore case studies confirmed the accuracy of the rheology and hydraulics models for low-ECD fluids and the fluids’ superior performance at high temperatures. The low-ECD clay-free IEFs can be accurately designed to provide superior wellbore pressure management and wellbore stability. This work is crucial for narrow-margin and high-temperature wells.
Improving ASP Performance in Carbonate Reservoir Rocks Using Hybrid-Alkali
Authors: Al-Murayri Mohammed Taha , Kamal Dawoud Suliman , Suniga Pearson , Fortenberry Robert , Britton Chris , Pope Gary A. , Liyanage Pathma Jith , Jang Sung Hyun , Upamali Karasinghe A.N. 
Published: October 2017

Abstract
Waterflood oil recovery in many carbonate oil reservoirs is low due to both high residual oil saturations and low sweep efficiency because of high heterogeneity. An example is the Sabriyah Mauddud reservoir in Kuwait. Alkaline-surfactant polymer flooding (ASP) has great potential for enhanced oil recovery both because ASP flooding reduces residual oil saturation and because of the polymer improves sweep efficiency. Unfortunately, the initial ASP coreflood experiments using conventional alkali showed unacceptably high surfactant retention in the reservoir cores. Several approaches to reducing surfactant retention were tested. Numerous strategies such as the use of chelating agents, sacrificial agents and chemical gradients were tested to reduce retention. The most effective strategy used a hybrid-alkali (NaOH + Na2CO3) in addition to a hydrophilic polymer drive containing a novel co-solvent. In this approach injection pH was increased to 12.5, compared to 10.5 using only Na2CO3. Such high pH is undesirable in sandstones because of reactions with silica minerals, but theexperimental results described here suggest the process is suitable for carbonate reservoirs. With this approach, both low surfactant retention and high oil recovery were achieved in very tight reservoir cores (8-35 mD). This novel approach was validated in a live oil coreflood using preserved cores to represent the reservoir material in the most rigorous way possible. This significant decrease in surfactant retention makes ASP flooding in the Sabriyah Mauddud reservoir viable.