Monitoring the Pulse of a Well Through Sealed Wellbore Pressure Monitoring, a Breakthrough Diagnostic With a Multi-Basin Case Study

2020 ◽  
Author(s):  
Kyle Haustveit ◽  
Brendan Elliott ◽  
Jackson Haffener ◽  
Chris Ketter ◽  
Josh O'Brien ◽  
...  
Keyword(s):  
Pressure Monitoring ◽  
Wellbore Pressure

An Eagle Ford Case Study: Monitoring Fracturing Propagation Through Sealed Wellbore Pressure Monitoring

2021 ◽  
Author(s):  
Kourtney Brinkley ◽  
Trevor Ingle ◽  
Jackson Haffener ◽  
Philip Chapman ◽  
Scott Baker ◽  
...  
Keyword(s):  
High Stress ◽  
Horizontal Distance ◽  
Economic Optimization ◽  
Pressure Monitoring ◽  
Eagle Ford ◽  
Fracture Geometry ◽  
Field Development ◽  
Wellbore Pressure ◽  
Stimulation Of

Abstract This case study details the use of Sealed Wellbore Pressure Monitoring (SWPM) to improve the characterization of fracture geometry and propagation during stimulation of inter-connected stacked pay in the South Texas Eagle Ford Shale. The SWPM workflow utilizes surface pressure gauges to detect hydraulically induced fracture arrivals athorizontal monitor locations adjacent to the stimulated wellbore (Haustveit et al. 2020). A stacked and staggered development in Dewitt County provided the opportunity to jointly evaluateprimary completion and recompletion efforts spanning three reservoir target intervals. Fivemonitor wells at varying distances across the unit were employed for SWPM during the stimulation of four wells. An operational overview, analysis of techniques, correlation with seismic attributes, image log interpretations, and fracture model calibration are provided. Outputs from this workflow allow for a refined analysis ofthe overall completion strategy. The high-density, five well monitor array recorded a total of 160 fracture arrivals at varying vertical and lateral distances, with far-field fracture arrivalsprovidingsignificant insight into propagation rates and geometry. Apronounced trend occurred in both arrival frequency and volumes pumped as monitor locations increased in distance from the treatment well. Specific to target zone isolation, it was identified that traversing vertically in section through a high stress interval yielded a 30% reduction inarrival frequency. An indirect relationship between horizontal distance and arrival frequency was also observed when monitoring from the same interval. A decrease in fracture arrivals from 70% down to 8% was realized as offset distance increased from 120 to 1,700 ft. The results from this study have proven to be instrumental in guiding interdisciplinary discussion. Assessing fracture geometry and propagation during stimulation, particularly in the co-development of a stacked pay reservoir, is paramount to the determination of proper completion volume, perforation design, and well spacing. Leveraging the observations of SWPM ultimately provides greater confidence in field development strategy and economic optimization.

A Semianalytical Modeling Approach for Hydraulic Fracture Initiation and Orientation from Perforated Wells

2021 ◽  
pp. 1-15
Author(s):  
Andreas Michael ◽  
Ipsita Gupta
Keyword(s):  
Tensile Strength ◽  
Closed Form ◽  
Hydraulic Fracture ◽  
Fracture Initiation ◽  
Barnett Shale ◽  
Transverse Fracture ◽  
Breakdown Pressure ◽  
Analytical Approximations ◽  
Wellbore Pressure

Summary Accurate prediction of fracture initiation pressure and orientation is paramount to the design of a hydraulic fracture stimulation treatment and is a major factor in the treatment's eventual success. In this study, closed-form analytical approximations of the fracturing stresses are used to develop orientation criteria for relative-to-the-wellbore (longitudinal or transverse) fracture initiation from perforated wells. These criteria were assessed numerically and found to overestimate the occurrence of transverse fracture initiation, which only takes place under a narrow range of conditions in which the tensile strength of the rock formation is lower than a critical value, and the breakdown pressure falls within a “window.” For a case study performed on the Barnett Shale, transverse fracture initiation is shown to take place for breakdown pressures below 4,762 psi, provided that the formation's tensile strength is below 2,482 psi. A robust 3D finite volume numerical model is used to evaluate solutions for the longitudinal and transverse fracturing stresses for a variable wellbore pressure, hence developing correction factors for the existing closed-form approximations. Geomechanical inputs from the Barnett Shale are considered for a horizontal well aligned parallel to the direction of the least compressive horizontal principal stress. The corrected numerically derived expressions can predict initiation pressures for a specific orientation of fracture initiation. Similarly, at known breakdown pressures, the corrected expressions are used to predict the orientation of fracture initiation. Besides wellbore trajectory, the results depend on the perforation direction. For the Barnett Shale case study, which is under a normal faulting stress regime, the perforations on the side of the borehole yield a wider breakdown pressure window by 71% and higher critical tensile strength by 32.5%, compared to perforations on top of the borehole, implying better promotion of transverse fracture initiation. Leakage of fracturing fluid around the wellbore, between the cemented casing and the surrounding rock, reduces the breakdown pressure window by 11% and the critical tensile strength by 65%. Dimensionless plots are employed to present the range of in-situ stress states in which longitudinal or transverse hydraulic fracture initiation is promoted. This is useful for completion engineers; when targeting low permeability formations such as shale reservoirs, multiple transverse fractures must be induced from the horizontal wells, as opposed to longitudinal fracture initiation, which is desired in higher permeability reservoirs or “frac-and-pack” operations.

Turning a Breakthrough Technology into a Scalable Process: Sealed Wellbore Pressure Monitoring

2021 ◽  
Author(s):  
Jessica Iriarte ◽  
Samid Hoda ◽  
Ryan Guest ◽  
Mary Van Domelen
Keyword(s):  
Hydraulic Fracturing ◽  
Pressure Gauge ◽  
Diagnostic Technique ◽  
Fracture Network ◽  
Machine Learning Algorithms ◽  
Valuable Insight ◽  
Pressure Monitoring ◽  
Interpretation Biases ◽  
Wellbore Pressure ◽  
Treatment Data

Abstract A breakthrough patent-pending pressure diagnostic technique using offset sealed wellbores as monitoring sources was introduced at the 2020 Hydraulic Fracturing Technology Conference. This technique quantifies various hydraulic fracture parameters using only a surface gauge mounted on the sealed wellbore(s). The initial concept, operational processes, and analysis techniques were developed and deployed by Devon Energy. By scaling and automating the process, Sealed Wellbore Pressure Monitoring (SWPM) is now available to the industry as a repeatable workflow that greatly reduces analysis time and improves visualizations to aid data interpretations. The authors successfully automated the SWPM analysis procedure using a cloud-based software platform designed to ingest, process, and analyze high-frequency hydraulic fracturing data. The minimum data for the analysis consists of the standard frac treatment data combined with the high-resolution pressure gauge data for each sealed wellbore. The team developed machine learning algorithms to identify the key events required by a sealed wellbore pressure analysis: the start, end, and magnitude of each pressure response detected in the sealed wellbore(s) while actively fracturing offset wells. The result is a rapid, repeatable SWPM analysis that minimizes individual interpretation biases. The primary deliverables from SWPM analyses are the Volumes to First Response (VFR) on a per stage basis. In many projects, multiple pressure responses within a single stage have been observed, which provides valuable insight into fracture network complexity and cluster/stage efficiency. Various methods are used to visualize and statistically analyze the data. A scalable process facilitates creating a statistical database for comparing completion designs that can be segmented by play, formation, or other geological variations. Completion designs can then be optimized based upon the observed well responses. With enough observations and based on certain spacings, probabilities of when to expect fracture interactions could be assigned for different plays.

scholarly journals Study on the Surge-Swab Pressure considering the Effect of the Cutting Plug in Shale Drilling

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Tianyi Tan ◽  
Hui Zhang ◽  
Xusheng Ma ◽  
Yufei Chen
Keyword(s):  
Horizontal Wells ◽  
Wellbore Stability ◽  
Pressure Management ◽  
Accurate Calculation ◽  
Wellbore Instability ◽  
Wellbore Pressure ◽  
The Difference ◽  
Open Pipe ◽  
Frequent Problem

Wellbore instability is a frequent problem of shale drilling. Accurate calculation of surge-swab pressures in tripping processes is essential for wellbore pressure management to maintain wellbore stability. However, cutting plugs formed in shale horizontal wells have not been considered in previous surge-swab pressure models. In this paper, a surge-swab pressure model considering the effect of cutting plugs is established for both open pipe string and closed pipe string conditions; In this model, the osmotic pressure of a cutting plug is analyzed. The reduction of cutting plug porosity due to shale hydration expansion and dispersion is considered, ultimately resulting in an impermeable cutting plug. A case study is conducted to analyze swab pressures in a tripping out process. The results show that, in a closed pipe condition, the cutting plug significantly increases the swab pressures below it, which increase with the decrease of cutting plug porosity and the increase of cutting plug length. Under the give condition, the swab pressure at the bottom of the well increases from 3.60 MPa to 8.82 MPa due to the cutting plug, increasing by 244.9%. In an open pipe string condition, the cutting plug affects the flow rate in the pipes and the annulus, resulting in a higher swab pressure above the cutting plug compared to a no-cutting plug annulus. The difference increases with the decrease of the porosity and the increase of the length and the measured depth of the cutting plug. Consequently, the extra surge-swab pressures caused by cutting plugs could result in wellbore pressures out of safety mud density window, whereas are ignored by previous models. The model proposes a more accurate wellbore pressure prediction and guarantees the wellbore stability in shale drilling.

Geomechanical Implications of Reservoir Depletion vis-à-vis Post-Blowout Well Capping: A Gulf of Mexico Case Study

2021 ◽  
Author(s):  
Andreas Michael
Keyword(s):  
Gulf Of Mexico ◽  
Fracture Initiation ◽  
In Situ Stress ◽  
Single Step ◽  
Reservoir Rock ◽  
Tensile Fracture ◽  
Well Control ◽  
Wellbore Pressure

Abstract Reservoir depletion can impose major implications on wellbore integrity following blowouts. A loss-of-well-control event can lead to prolonged post-blowout discharge from the wellbore causing considerable reservoir depletion in a well's drainage area. Fractures initiated and propagated during well capping procedures following an offshore blowout can lead to reservoir hydrocarbons broaching the seafloor. In this paper, reservoir depletion is examined for a case study on actual deepwater Gulf of Mexico (GoM) parameters, evaluating analytically its impacts on in-situ reservoir conditions, hence assessing the likelihood of longitudinal or transverse fracture initiation during post-blowout well capping. The reservoir rock is modeled as a porous-permeable medium, considering fluid infiltration from the pressurized wellbore. A novel analytical workflow is presented, which encompasses the major effects of reservoir depletion on the (i) in-situ stress state, (ii) range of in-situ stress states stable against shear fault slippage, and (iii) limits of tensile fracture initiation. The geomechanical implications of each individual effect on post-blowout well capping is discussed with the individual results illustrated and analyzed altogether on dimensionless plots. These plots are useful for engineers when making contingency plans for dealing with loss-of-well-control situations. The workflow is demonstrated on a case study on parameters taken from the M56 reservoir, where the April 20, 2010 blowout took place at the MC 252-1 "Macondo" well. A smaller post-blowout discharge flowrate is shown to increase the shut-in wellbore pressure build-up at any given time-point following well capping, whereas an increased post-blowout discharge period leads to a lower shut-in wellbore pressure build-up, hence reducing the likelihood of a fracture initiation scenario and vice versa. Assuming a robust wellbore architecture, the most likely location of fracture initiation is the top of the M56 reservoir within the openhole section of the Macondo well. The critical discharge flowrate, an established indicator for fracture initiation during well capping using information from the post-blowout discharge stage is employed, pointing that fracture initiation is highly-unlikely for the assessed parameters. Nevertheless, fracture initation during post-blowout well capping remains a real possibility in the overpressurized, stacked sequences of the GoM. Finally, the model is extended to an "incremental"/multi-step capping stack shut-in imposed over a longer time-period (e.g. 1 day than abruptly over a single-step) to suppress the wellbore pressure build-up, if necessary to avoid fracture initiation.

Mining pressure monitoring and analysis in fully mechanized backfilling coal mining face-A case study in Zhai Zhen Coal Mine

2015 ◽  
Vol 22 (5) ◽  
pp. 1965-1972 ◽  
Author(s):  
Qiang Zhang ◽  
Ji-xiong Zhang ◽  
Tao Kang ◽  
Qiang Sun ◽  
Wei-kang Li
Keyword(s):  
Coal Mining ◽  
Coal Mine ◽  
Pressure Monitoring ◽  
Mining Face ◽  
Mining Pressure

Pressure-Monitoring Technique Uses Sealed Wellbore Pressure as Source

2021 ◽  
Vol 73 (03) ◽  
pp. 51-52
Author(s):  
Chris Carpenter
Keyword(s):  
Closed System ◽  
Growth Rates ◽  
Pressure Gauge ◽  
Local Deformation ◽  
Pressure Response ◽  
Pressure Monitoring ◽  
Fracture Intersection ◽  
Monitoring Technique ◽  
Wellbore Pressure ◽  
Fracture Growth

This article, written by JPT Technology Editor Chris Carpenter, contains highlights of paper SPE 199731, “Monitoring the Pulse of a Well Through Sealed Wellbore Pressure Monitoring: A Breakthrough Diagnostic With a Multibasin Case Study,” by Kyle Haustveit, SPE, Brendan Elliott, SPE, and Jackson Haffener, SPE, Devon Energy, et al., prepared for the 2020 SPE Hydraulic Fracturing Technology Conference and Exhibition, The Woodlands, Texas, 4-6 February. The paper has not been peer reviewed. A pressure-monitoring technique using an offset sealed wellbore as a monitoring source has led to advancements in quantifying cluster efficiencies of hydraulic stimulations in real time. Sealed wellbore pressure monitoring (SWPM) is a low-cost, nonintrusive method used to evaluate and quantify fracture-growth rates and fracture-driven interactions during a hydraulic stimulation. The measurements can be made with only a surface pressure gauge on a monitor well. To date, more than 1,500 stages have been monitored using the technique. The complete paper reviews multiple SWPM case studies, collected from projects in the Anadarko and Permian Delaware basins; this synopsis will concentrate on the concepts behind, and the validation of, the technique. Introduction SWPM is performed on a well that acts as a closed system. The well cannot be connected to a formation through perforations or other types of access points; the casing must be sealed. Uncompleted wells can be used if the shallowest perforations are isolated from the formation. In an existing producing well, a plug must be set above the shallowest perforations to create a closed system from the top of the plug to surface where the pressure measurement is recorded. The wellbore should be filled with low-compressibility fluid (e.g., completion brine) to amplify the pressure response created during monitoring. Fractures intersecting the sealed wellbore cause local deformation, which results in a small volume reduction in the closed system (system being the fluid volume inside of the casing) and generates a discernible and distinct pressure response. Pressure can be recorded either using a surface gauge or a downhole gauge. Multiple sealed wellbores can be used as monitor wells for a single treatment well, allowing for a more-detailed understanding of fracture growth rates during a stimulation. The field execution of SWPM is simple and does not require any tools to enter the wellbore. A surface gauge provides the necessary data needed to evaluate the fracture interactions with the monitor wellbore. There is no need to alter zipper operations if sealed wellbores are available. The main restriction SWPM introduces to operations is the necessity to leave new wellbores, designated as monitors, unprepped by not opening toe sleeves or shooting perforations for Stage 1 until monitoring of the offset treatment wells is complete. Because the pressure response in the monitor well is a result of a fracture intersection at the wellbore, the method reduces the uncertainty related to the location of the monitor point commonly associated with other offset pressure-monitoring techniques.

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