Day 2 Mon, February 20, 2023最新文献

{"title":"Utilization of Innovative Resin-Cement Blend to Enhance Wellbore Integrity","authors":"Wajid Ali, Faisal Abdullah Al-Turki, Athman Abbas, A. Al-Yami, V. Wagle, Ali Al-Safran","doi":"10.2118/213763-ms","DOIUrl":"https://doi.org/10.2118/213763-ms","url":null,"abstract":"A major challenge that is being occasionally faced during the well's lifecycle is the pressure buildup between the cemented casing annuli, also known as sustained casing pressure (SCP). Compromise of cement sheath integrity is one of the primary reasons for such a pressure buildup. This challenge prompted to develop such an isolation material that should enhance the mechanical properties of cement. The resin-cement blend system can be regarded as a novel technology to assure long term zonal isolation.\u0000 This paper presents the lab testing and application of the resin-cement system, where potential high-pressure influx was expected across a water-bearing formation. The resin-cement system was designed to be placed as a tail slurry to provide enhanced mechanical properties in comparison to a conventional slurry. The combined mixture of resin and cement slurry provided all the necessary properties of the desired product. The slurry was batch-mixed to ensure the homogeneity of resin-cement slurry mixture. The cement treatment was performed as designed and met all zonal isolation objectives.\u0000 Engineered solutions ultimately deliver the optimal asset value of the reservoir. During the last few decades, several laboratory investigations and field studies have been conducted to find solutions to the problem of SCP, which appears after primary or remedial cement jobs. Almost all these studies unanimously conclude that the conventional cement does not always endure the mechanical stresses imposed by the wellbore conditions and it often falls short in providing long term isolation beyond the production life of the well. When the resin is introduced into a cement slurry, it forms a dense, highly cross-linked matrix. The extent of the cross-linking reaction is governed primarily by volume, temperature, and time. The distribution of resin throughout the slurry provides a shock-absorbing tendency to the particulates of the cement. This feature increases the ductility and the resilience to withstand stress from load-inducing events throughout the life of the well. Resin-cement's increased compressive strength, ductility, and enhanced shear bond strength help to provide a dependable barrier that would help prevent future sustained casing pressure (SCP).","PeriodicalId":249245,"journal":{"name":"Day 2 Mon, February 20, 2023","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130921441","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sidetrack Trajectory Success Indicator","authors":"Graham Hitchcock, A. Watson, M. Alshalan","doi":"10.2118/213663-ms","DOIUrl":"https://doi.org/10.2118/213663-ms","url":null,"abstract":"\u0000 The drilling of a secondary wellbore departing from a primary wellbore, known as a sidetrack, is used for many reasons during wellbore construction. Sidetrack techniques and procedures are well established with all the major service companies. A typical sidetrack operation would consist of setting a deflector (whipstock), cutting a hole in the existing casing (window), and then drilling into the formation at the desired exit angle and direction (kick off) to produce a starting hole (rathole) for subsequent drilling. The sidetrack milling assembly would then be Pulled Out of Hole and the drilling bottom hole assembly (BHA) run in hole to continue drilling the secondary wellbore trajectory. If for some reason, the casing exit and desired departure of the sidetrack is not obtained, this will remain unknown until the subsequent drilling operation with Logging While Drilling (LWD) tools are run in hole and have extended the rathole. The failure to obtain and recognize the desired kickoff departure prior subsequent drilling operations can lead to significant Non Productive Time (NPT) and subsequent rectification costs.\u0000 This paper describes the development and successful testing of a compact sensor package located near the front of the sidetrack milling assembly. The sensor package is activated at surface and records inclination data during the sidetrack operation. When the sidetrack milling assembly is pulled out of hole the sensor is read wirelessly using a handheld reader once the milling assembly is at surface. The reader gives the operator a visual confirmation, or otherwise, that the desired sidetrack kick off departure has been achieved allowing informed decisions to be made on the next operational stage.","PeriodicalId":249245,"journal":{"name":"Day 2 Mon, February 20, 2023","volume":"224 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133270118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Laboratory Assessment of Rock Wettability Effect on Polymer Retention in Carbonates","authors":"Álvaro Hernández-Morales, Muhammad Mushtaq, Anoo Sebastian, Emad W. Al-Shalabi, W. Alameri","doi":"10.2118/213449-ms","DOIUrl":"https://doi.org/10.2118/213449-ms","url":null,"abstract":"\u0000 Polymer retention is one of the controlling aspects of an effective polymer flooding process. Very few studies discussed the effect of rock wettability on polymer retention, with no consensus on the outcome. While some studies described that oil-wet rocks have low polymer retention, others reported the opposite. This work investigates the effect of rock wettability on the retention of an ATBS-based polymer onto carbonates at high salinity and moderate temperature conditions. In this study, static and dynamic retention tests of an ATBS-based polymer onto high permeable Indiana limestone outcrops were conducted in both absence and presence of oil. These tests were conducted at 50 °C using representative crude oil and formation water (167,114 ppm) of Middle East carbonate reservoir conditions. For the two-phase dynamic tests, the cores were aged at 90 °C for different times (8 hours, 3 and 14 days) to create different wettability conditions, which were verified by Amott index to water. Then, polymer retention and in-situ rheology, including RF and RRF, were determined. Similar procedure was followed for dynamic single-phase tests, but without core aging. Furthermore, single- and two-phase static tests were conducted under identical experimental conditions to compare the retention values.\u0000 The results of Amott index to water showed that the selected aging times were suitable for creating different wettability conditions, where cores with longer aging times had a wettability more towards oil-wetting state. It was observed that three-days period of aging was enough to restore the wettability of Indiana limestone outcrops used in this study. Also, polymer dynamic retention was found lower in the presence of oil by about 35 to 47% as opposed to its absence. A further decrease in polymer retention by 14% was obtained for cores with a more oil-wetting condition resulting in a retention level of about 25 µg/g-rock. This is because oil-wet cores have a larger and effective surface area covered by the oil film, leading to a lower surface area left for polymer adsorption as opposed to cores with a wettability towards a more water-wetting state. On the other hand, single- and two-phase static adsorption tests showed non-comparable and very high retention values in the range of 305-337 µg/g-rock. This finding indicates that aging of the rock in such tests does not play a decisive role in obtaining representative polymer retention levels comparable to the dynamic tests. This study is one of the very few works that discuss the effect of rock wettability on polymer retention in carbonates. The study provides an essential insight into the inconclusive results in the literature by highlighting the role of wettability effect on polymer retention based on both static and dynamic retention tests.","PeriodicalId":249245,"journal":{"name":"Day 2 Mon, February 20, 2023","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131971555","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Combining Nuclear Magnetic Resonance with Deep and Ultradeep Azimuthal Resistivity Images in Carbonate Reservoirs Links Reservoir Structure with Rock Type while Drilling","authors":"O. Ramadan, U. Idris, M. Van Steene, G. Santoso","doi":"10.2118/213667-ms","DOIUrl":"https://doi.org/10.2118/213667-ms","url":null,"abstract":"\u0000 Deep and ultradeep azimuthal resistivity images enable precise well placement inside the reservoir structure. However, they deliver limited information about the quality of the reservoir, especially in carbonates, where large pore-size variations are common. Combining the deep and ultra-deep resistivity images with logging-while-drilling (LWD) nuclear magnetic resonance (NMR) measurements enables linking reservoir structure with rock types while drilling for optimal well placement.\u0000 The NMR data is used to generate four petrophysical rock types while drilling: RT-1 has good porosity and long T2 components, indicating large pores; RT-2 has good porosity but medium T2 components, indicating smaller pores; RT-3 has medium porosity and long T2 components; and RT-4 has medium or low porosity and medium or short T2 components, indicating the worst facies. The first step in identifying these rock types is running factor analysis on the NMR data. This data analysis method is used to reduce a large dataset to a smaller number of underlying components. Used with NMR data, the method typically produces 9 to 11 factors and their associated poro-fluid facies, which are further reduced to four to ease interpretation.\u0000 The method was implemented in two wells. The first had a single lateral, which was geosteered using ultradeep azimuthal resistivity images and NMR. The borehole entered the reservoir from the bottom. The NMR indicated a large section of RT-4, so the well was steered to cross into the upper reservoir lobe in search of better rock type. The best rock type, RT-2, was discovered at 8 ft true vertical depth (TVD) below the top of the reservoir, and geosteering continued within that rock type.\u0000 The second well was a trilateral, geosteered with deep azimuthal resistivity imaging and NMR measurements. The initial lateral penetrated the first reservoir layer, where the NMR indicated RT-3 rock type with high permeability. After about 500 ft of drilling, the target reservoir layer was identified below the wellbore, and the well was steered into it. The NMR initially indicated that the rock type was RT-2, but combining the reservoir structure from the deep azimuthal resistivity image inversion with NMR rock typing confirmed that the upper section of the second layer had the best rock type, namely RT-1. Based on this finding, the second and third laterals were placed in the upper part of the same reservoir layer, with an excellent net-to-gross ratio.\u0000 Association of NMR rock typing and reservoir structure while drilling is a new methodology that combines the strengths of both techniques to optimize reservoir understanding and well placement.","PeriodicalId":249245,"journal":{"name":"Day 2 Mon, February 20, 2023","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127831946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrated Modelling and Forecasting of Gas Injection Pilot in a Heterogeneous Oolitic Carbonate Reservoir, West Kuwait","authors":"A. Pradhan, H. Al-Mayyan, K. Ziyab, P. Nurafza, Sumit S. Mishra, Arpit Khandelwal, A. Srivastava, T. Faulkner","doi":"10.2118/213408-ms","DOIUrl":"https://doi.org/10.2118/213408-ms","url":null,"abstract":"\u0000 Hydrocarbon gas flooding is one of the most applied miscible EOR processes in the oil industry. The process becomes extremely challenging in heterogeneous carbonate reservoirs. An inverted four-spot hydrocarbon (HC) gas injection pilot has been under execution since 2016 to address these challenges, in a heterogeneous multi-layered Oolitic carbonate reservoir in West Kuwait. The pilot consisted of a pre-flush phase of water injection (2016-19) followed by a gas injection phase (2021-2022). This paper describes modelling and history matching of pre-flush waterflood phase and forecasting ahead of gas injection phase.\u0000 The pre-flush waterflood was carried out sequentially into four target layers, injecting a range of pore volumes in each layer and gathering wealth of pilot data including Inter-Well Tracer Test (IWTT), PLT/ILT, time-lapse saturation logging, coring, and VIT to assess the impact of heterogeneity on the displacement process. Integrated review of the acquired dataset was conducted leading to better understanding of the reservoir performance. Model calibration was challenging as variable tracer arrival and concentration profiles indicated high heterogeneity. Detailed compositional simulation studies were undertaken on hybrid sector models of the pilot area created from full-field models, incorporating newly drilled well tops, reservoir properties and full-field fluxes. High-level experimental designs were conducted leading to dynamic sector models calibration, by identifying layer connectivity and baffle introduction as the main modelling gaps. The results showed baffles to vertical flow play a key role in reservoir and fluid flow performance.\u0000 The knowledge gained from the pre-flush pilot data review and modelling were instrumental in forecasting the pilot gas injection performance. Activities undertaken to forecast the gas injection pilot performance include a two-pronged strategy of using calibrated hybrid sector model realizations and simple box models. The box-models captured range of gas injection phase outcomes on a simplified finer resolution of injector-producer models, testing gas injection strategy sensitivities without any dependency on history match quality, while the calibrated hybrid sector models offered pilot gas injection outcomes accounting for pilot area wells interaction and full-field streamline fluxes, testing gas injection programme robustness. The approach tremendously helped with the surveillance programme design of the pilot gas injection phase.\u0000 Novel integrated modelling workflows, history matching techniques and forecasting approaches were used in this study of a complex heterogeneous multi-layered carbonate reservoir. Results of which assisted KOC to plan and successfully implement the pilot gas injection phase and formulate a robust surveillance programme to capture the effects of gas injection process. Further, it will help in designing a road map for commercial deployment of gas injection on a field sc","PeriodicalId":249245,"journal":{"name":"Day 2 Mon, February 20, 2023","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115445686","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Establishing Critical Gas Velocities for Liquid Loading in Deviated Gas Wells","authors":"C. Ejim","doi":"10.2118/213620-ms","DOIUrl":"https://doi.org/10.2118/213620-ms","url":null,"abstract":"\u0000 Severe liquid loading in wells producing from some wet gas reservoirs, results in the well being unable to transport fluids to surface. In field applications, liquid loading is known to be more pronounced in deviated wells than in vertical wells. This study highlights a methodology to estimate the critical velocities for liquid loading in inclined gas wells. Knowledge and use of the technique is of importance to production engineers and stakeholders of a gas asset.\u0000 Test data from a 3-inch diameter line with inclination from vertical to near horizontal was obtained from open literature. For each deviation angle, and based on the test conditions, a correlation for liquid holdup in inclined wells was used to determine the void fraction at the region of interest. The corresponding maximum and average film thicknesses, as well as the interfacial friction factor were determined. The principle of momentum conservation for a deviated tubing was applied and the superficial critical gas velocities for liquid loading were estimated. These estimated velocities were compared to those obtained from the test data.\u0000 For the different superficial liquid velocities investigated, the estimated critical gas velocities increased with increasing deviation from vertical. The maximum critical velocity was reached when the deviation angle was about 40° to 50° from vertical. Beyond this point, the critical gas velocity decreased with increasing deviation angle from vertical up to the near-horizontal inclination. The results also showed that the gas critical velocity increased with increasing liquid superficial velocity. The overall trend of the critical velocity variation was similar to the trend in the actual test data obtained from open literature. The range of estimated critical gas velocities varied from about 9 m/s to about 35 m/s, with overall Root Mean Square Errors between 3.3 m/s and 6 m/s. In conclusion, results from this methodology was able to give a first-hand estimate of critical superficial velocities for inclined gas wells.\u0000 This work presents a methodology to estimate critical gas velocities for inclined gas wells. This knowledge is important for field engineers and asset managers in the planning and production phases of gas wells. The benefits include optimizing the gas completion hardware during design, and maximizing gas flow rates during production operation. Overall, this increases the economic bottom-line for the field operator.","PeriodicalId":249245,"journal":{"name":"Day 2 Mon, February 20, 2023","volume":"35 2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116419661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of Slickwater Refrac Treatments Utilizing Mechanical and Formation Diversion Techniques ao Extend Wells Productivity","authors":"Wafaa Alnakhli, Zeyad Habiballah, S. Baki, Abdullah Alzamil, J. Rueda, Abdulrahman Alowaid, Karim Mechkak","doi":"10.2118/213233-ms","DOIUrl":"https://doi.org/10.2118/213233-ms","url":null,"abstract":"\u0000 The objective of the paper is to evaluate the successful implementation of refrac treatment in unconventional wells with initial completion and stimulation practices. The implementation of refracturing treatment utilizing various diverter systems proved to be operationally feasible, increase productivity, and extend well life cycle.\u0000 Slick-water refrac practice relies on the combination of adding additional clusters through e-coil within previously stimulated clusters and utilizing mechanical or chemical diverters to plug dominant clusters, allowing the treatment to stimulate newly added or poorly contributing clusters. A fit-for-purpose criteria was developed for proper diverter selection, number and spacing of additional clusters, diverter drop systems, enhanced pumping schedules, and contingency plans.\u0000 The approach had been utilized in several wells, previously stimulated with various fluid systems and job volumes, completed with different completion types and sizes, and through numerous diverter types and drop systems, with notable success from operational and production point of view. Clear indications of effective diversion and stimulation were observed based on pressure response during diverter drop and treatment cycles, as well as an increased wells productivity. In conclusion, the application of refrac approach proved to be operationally feasible while allowing for an enhanced well performance post the refrac treatment.\u0000 The implemented combined approach of additional clusters, optimized diverter volumes, adjusted pumping schedules, and multiple diverter drop options offer several benefits in multiple categories: Operational (allowing for on-the-fly addition of diverters and continues cyclic pumping, and preventing the occurrence of screenouts during the refrac treatment), Technical (increasing the stimulated reservoir volume and contact with the formation), and Productivity (enhancing well performance and increasing well life cycle)","PeriodicalId":249245,"journal":{"name":"Day 2 Mon, February 20, 2023","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128777153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tailored Engineering Cementing Solution to Maintain Well Integrity in Shallowest Liner for Underground Gas Storage Project - Case History from Southwest China","authors":"Fangfang Li, Devesh Bhaisora, Huang Yue","doi":"10.2118/213579-ms","DOIUrl":"https://doi.org/10.2118/213579-ms","url":null,"abstract":"\u0000 Underground gas storage (UGS) wells have emerged as a strategic solution in China. Success of UGS projects largely depends upon maintaining long term well integrity. Cement slurries that are placed across a wellbore should exhibit superior cement bonding as evidenced through a cement bond log (CBL) and long-term integrity to sustain the cyclic stress change by the injection and production process. Such slurries should have improved mechanical properties and the job execution should follow all cementing best practices.\u0000 The well architecture included a 9 5/8-in. surface casing and a 7-in. production liner. The 7-in. Liner was run inside an 8.5-in. open hole and extended to surface using a tie-back liner. This well architecture should have a superior quality of cement across the entire liner. Multiple Finite Element Analysis (FEA) runs were performed to determine an optimum Young's modulus and Poisson Ratio for the cement slurry. These rigorous tests can take weeks to complete. As the well was shallow, to cover a wide range of well profiles, three different slurries were tested prior to the job.\u0000 The initial mud weight planned for the well was in the range of 1.25 g/cm3 to 1.4 g/cm3. Due to gas influx, the mud density in the section was increased to 1.90 g/cm3. However, losses were also encountered at this mud density. Hydraulic modelling was revised, and slurry rheology and pumping rates were optimized to ensure equivalent circulation density (ECD) control within the pore pressure and fracture gradient window. Displacement rates were optimized to facilitate good displacement efficiency for hole cleaning. The slurry design was tailored with special additives to provide a synergetic effect of improving mechanical properties and minimizing seepage losses. Multiple computational fluid dynamics (CFD) runs were performed to evaluate the cementing job quality and based on the simulations it was decided to increase the cement volume to minimize any impact of contamination. The cementing job was performed with no operational issues and cement returns were observed above the top of the liner. Two different cement evaluation logs - CBL and ultra-sonic log, were conducted and showed good cement quality in the open hole section, meeting the well objectives.\u0000 With this successful implementation, the tailored engineered cementing solution was highly recognized. The design and execution methodology were highlighted as the guideline for further successful cementing operations in UGS projects. This study shows a fully comprehensive and scientific way to improve cementing quality for long-term well integrity for UGS projects.","PeriodicalId":249245,"journal":{"name":"Day 2 Mon, February 20, 2023","volume":"2016 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130017452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Innovative and Independent Method for Formation Strengths and Facies Identification Using Real-Time Downhole Drilling Data, and its Application in Geosteering for Optimal Well Placement","authors":"U. Prasad, F. Jonsbråten, D. Holbrough, C. Saint","doi":"10.2118/213633-ms","DOIUrl":"https://doi.org/10.2118/213633-ms","url":null,"abstract":"\u0000 Understanding of rock strength, and its variability along the length of the well, is essential for building an efficient well trajectory during geosteering operations. Traditionally, drill cuttings, surface gas analysis, measurements while drilling (MWD) data and Logging While Drilling (LWD) measurements have been used to optimize trajectories. Rock mechanical properties, derived from petrophysical well logs are key to drilling, production and recovery potential of the well: However, in a vast majority of geosteered wells, LWD data and the derived rock properties are not available thus conforming to the given well trajectory and successful Geosteering is difficult. In comparison, real-time downhole drilling data is usually available but rarely used. An innovative, reliable and robust method is presented which capitalizes on downhole MWD and LWD data.\u0000 This method uses downhole weight-on-bit (WOB), rotational speed (RPM), downhole torque (TOR), and rate-of-penetration (ROP), to characterize the mechanical specific energy (MSE) consumed in the drilling process. The specific bit diameter (D), mud-weight (MW) and depth (TVD) of drilling are also used in the model. If the task is to optimize drilling parameters for a new formation (e.g. drill-off-test), then \"minimum\" MSE is captured. However, if the task is continuous drilling, geosteering, and creating a stable well for its subsequent stage and cluster-wise hydraulic fracture design, then \"instantaneous\" MSE is used to infer strength of the rocks and their variation along the length of the well.\u0000 An offshore well from the North Sea was initially selected to apply the concept of the above technology on several post well data analyses using downhole drilling data together with average ROP and RPM. Further, the same concept was used in a real-time application with downhole drilling data. The gamma-ray, neutron porosity, density and resistivity were analyzed and compared with the MSE obtained. Drilling efficiency was assumed based on prescribed industry standards for calculating confined compressive strength (CCS), Internal Friction Angle (IFA), and unconfined compressive strength (UCS). The UCS estimated at a scale of 1.0-1.5″ scale versus depth-of-cut (scale of 0.1-0.5″) resolution matched well with log based UCS from density, porosity and acoustic logs. Calculated results are compared with lab-based core test data where available. The details of these calculations and successful application to Geosteering are presented.\u0000 These strength estimates are of benefit to directional drilling engineers for safe and economic well placement along optimum well trajectory, better well production and economic recovery from successive multi-stage and stage-and-cluster hydraulic fracturing designs. An ‘Efficiency’ Factor’ used in the process is discussed which originates from strengthening of rocks due to friction, chip-hold-down effect on cuttings, strengthening due to dilatancy, and cuttings-extrusion like behav","PeriodicalId":249245,"journal":{"name":"Day 2 Mon, February 20, 2023","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128896552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Industry's First Real-Time Pseudo Gamma Measurements From an Instrumented Steerable Motor Using High-Frequency Drilling Dynamics Sensors","authors":"J. Sugiura, Steve Jones","doi":"10.2118/213650-ms","DOIUrl":"https://doi.org/10.2118/213650-ms","url":null,"abstract":"\u0000 Downhole drilling motors are the workhorse of our industry and are used on almost every land well drilled globally. This makes an instrumented drilling motor the perfect tool for geosteering with near-bit inclination, drilling-dynamics and formation-identification sensors. Already proven drilling motor technology has been upgraded with miniature embedded sensors to provide real-time continuous inclination, advanced drilling dynamics, and pseudo-formation-identification data. The sensors are sized to mount into existing drilling motor components without adding length or compromising the mechanical integrity.\u0000 The high-frequency drilling-dynamics measurements, including lateral vibrations, axial vibrations, stick-slip, high-frequency torsional oscillation (HFTO) and motor back-drive dynamics are measured in the motor. The sensor unit applies advanced signal processing routines to the high-frequency vibration measurements downhole and converts the vibration data into pseudo gamma (pGamma) measurements, which have been correlated with measurement-while-drilling (MWD) gamma measurements in lateral wellbores. pGamma can alert the driller as soon as the bit starts cutting new formations, as compared with traditional real-time gamma measurement, which is about 40-50ft away from the drill bit. In addition, the sensor units measure bit and string rotation speeds below and above the mud motor, enabling the detection of the motor output rotation speed and motor back-drive dynamics in real time.\u0000 Real-time near-bit inclination, advanced drilling-dynamics and geosteering measurements have been provided in a mud motor without compromising mechanical integrity or directional response. The real-time inclination, drilling dynamics data, and pseudo-gamma measurements from the instrumented motor are integrated into our drilling advisory system to enhance the drilling efficiency and wellbore placement accuracy.","PeriodicalId":249245,"journal":{"name":"Day 2 Mon, February 20, 2023","volume":"266 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122660309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}