Day 1 Mon, November 11, 2019最新文献

{"title":"Evaluation of Probability Point Estimate Methods for Uncertainty Analysis of Hydrocarbon in Place as an Alternative Techniques to Monte Carlo Simulation","authors":"H. Algdamsi, A. Amtereg, Ammar Agnia, Gamal A. Alusta, Ahmed Alkouh","doi":"10.2118/197487-ms","DOIUrl":"https://doi.org/10.2118/197487-ms","url":null,"abstract":"\u0000 Typically, the Monte Carlo simulation (MCS) approach was generally applied to assess and quantify uncertainty in probabilistic reserve estimates and improve risk decision making, regrdless of that it can be quite computationally intensive, MCS method has the advantages of generating possible outcomes That contain more information relative to deterministic and scenario approach by taking into consideration the uncertainty associated with the range of various input variable. However, MCS entails that the probability distribution functions of all uncertain input parameter be entirely known, this might be an obstacle or limitation on successful implementation of MCS as subjectivity on the selection and definition of the input variable distributions and their characterization or due to incomplete information and lack of data will critically impact and limit both its proper application and interpretation of the results and consequently doubt statistically the robustness of the solution. This shortcoming of MCS and difficulty can be circumvented by other complementary method like the PEM, first-order second moment (FOSM) or Warren’s probability analysis methods which does not require a previous knowledge of the range and distribution shape to be defined or condition where information concerning uncertain parameter is not sufficient or reliable, moreover it has the advantage of less computational requirement to attain solution with comparable accuracy. This paper provides a comparative assessment of Point Estimate Method (PEM) for analyzing uncertainty of hydrocarbon in place as more practical alternative approaches to Monte Carlo simulation (MCS). Five PEM Rosenblueth, Harr, Che-Hao et al., Geethanjali et al. and Hong 2n scheme algorithm were used to model output uncertainty of hydrocarbon in Place for more than 20 field and predict P10, P50 and P90 using different PEM Technique. MSC result was generated for the same fields with an optimum number of samples for key variable using stability analysis and statistical measure of model run convergence which are benchmark to which the PEMs’ results are compared.","PeriodicalId":11061,"journal":{"name":"Day 1 Mon, November 11, 2019","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87294171","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":"Managed Pressure Drilling Tackles Pore Pressure Uncertainty While Drilling, Running Liner, and Cementing Across Multiple and Heterogonic Layered Reservoirs for the First Time in the United Arab Emirates","authors":"Maha Al Shehhi, S. Ameri, Ayoub Hadj-moussa, M. Saleh","doi":"10.2118/197273-ms","DOIUrl":"https://doi.org/10.2118/197273-ms","url":null,"abstract":"\u0000 This paper presents the novel approach used in drilling, running liner and cementing a development well across multiple reservoir with high pore pressure heterogeneity that has historically caused drilling hazards like differential stuck pipe, losses, well control and slow rate of penetrations.\u0000 Having depleted reservoirs and high-pressure reservoirs in the same hole section of well-A dictates that the mud weight must be higher than the higher reservoir pressure, which puts high differential pressure on the depleted reservoir and causes differential stuck pipe and losses. The uncertainty in determining the pore pressure adds another challenge as the mud weight must be higher than the expected pore pressure. Managed Pressure Drilling (MPD) addresses these challenges by enabling determining the pore pressure while drilling and adjusting the Equivalent Circulation Density (ECD) to be with the minimum overbalance.\u0000 MPD allowed drilling the section with (12.0 ppg) mud weight instead of the conventional mud weight (15.7 ppg). This has reduced the differential pressure between the depleted formation and the other formations significantly and enhanced the rate of penetration while balancing the well. It also proved that verifying the well's prognosis for pressure is essential in avoiding drilling hazards. Constant Bottom Hole Pressure (CBHP) mode of MPD was used to maintain the same ECD while drilling and connection to avoid well influx during pumps off events by compensating the annular friction pressure loss by surface back pressure. MPD was utilized too in running the 7″ liner and cementing it as a guarantee if the mud weight was too low to stabilize the well. The operation was carried out without safety or quality issue. The MPD system performance was with zero nonproductive time and the hole section was drilled shoe-to-shoe without any change the Rotating Control Device (RCD). This application showed an alternative preventive solution to differentially stuck pipe instead of the reactive one.\u0000 The approach explained in this paper is the first of its kind in ADNOC Onshore field. It involved altering the mud weight program strategically for more adaptive approach in dealing with drilling hazards like differential stuck pipe, losses and well control. The scheme involving MPD for running liner and cementing is the first ever in United Arab Emirates.","PeriodicalId":11061,"journal":{"name":"Day 1 Mon, November 11, 2019","volume":"55 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74621645","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":"Cased Hole Solution with Fast Neutrons and Sonic Reflective Waves in Tight Reservoirs","authors":"U. Bustos, C. Moya, D. Rose, T. Zhou, G. Martinez","doi":"10.2118/197423-ms","DOIUrl":"https://doi.org/10.2118/197423-ms","url":null,"abstract":"\u0000 Important hydrocarbon accumulations occur in tight rocks in Colombian areas. Those tight reservoirs consist of clean sandstones with matrix porosities in the 3% to 4% range, relatively complex mineralogy and naturally fractured. The success of achieving a representative formation evaluation relies on obtaining accurate porosity, oil, gas, water saturations, natural fractures detection and good estimates on reservoir permeability. Resistivity-based approaches are difficult to apply since reservoir conductivity is not only influenced by fluid type, but also by salinity (typically low in our reservoirs), variable tortuosity (mostly high in the matrix and very low in fractures) and very high formation resistivity (above 1,000 ohms.m). In addition, a combination of low pores volumes and a matrix not properly assessed, leads to high errors in the porosity determination with conventional logs (in a 3 – 4 p.u. reservoir, the porosity error computation can be as high as 50%). Uncertainties in porosity estimates also translates to uncertainties during saturation assessment.\u0000 Further challenges are found when attempting the saturation computation from resistivity logs. The tight sands are drilled with Oil Based Muds, creating a logging environment where only induction logs are possible. However, since the resistivity range in these rocks is above 1000 ohm.m range, the induction measurements are out of range in many of the target zones. Alternative formation evaluation methods for assessing fluids saturations, like magnetic resonance, sigma and carbon-oxygen logs cannot be applied below 10 porosity units; whereas dielectric measurements strongly depend on accurate porosity computations for deriving the hydrocarbon volume.\u0000 Some of these reservoirs, are also deep (in the 17,000 ft range) and close to foothills, where wellbore stability issues and narrow mud weight windows used for drilling, translates into higher risks for open-hole logging via logging while drilling or wireline conveyance, all of it detrimental to data acquisition in open hole. Therefore, the case studies presented in this paper were assessed in cased hole conditions.\u0000 In this paper, we present a solution that cover tight matrix and natural fractures assessment, at a level not previously achieved. At the tight matrix level, we carry out advanced nuclear spectroscopy with a new pulsed neutron device, that carry out simultaneous time domain and energy domain measurements. A new resistivity and salinity independent methodology for obtaining Gas saturation from a new measurement in the industry known as \"Fast Neutron Cross Section\" (FNXS), oil saturation from the total organic carbon (TOC) log, mineral volumes solved from formation elemental concentrations from energy domain, and porosity from hydrogen index obtained from the spectroscopy time domain, is presented. At natural fracture level, we make use of a Borehole Acoustic Reflection Service for deep natural fracture detection and spatial o","PeriodicalId":11061,"journal":{"name":"Day 1 Mon, November 11, 2019","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83493779","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":"Characterization of Hydraulic Fracture Barriers in Shale Play Through Core-Log Integration: Practical Integration of Machine Learning and Geological Domain Expertise","authors":"S. Perrier, A. Delpeint","doi":"10.2118/197307-ms","DOIUrl":"https://doi.org/10.2118/197307-ms","url":null,"abstract":"\u0000 \u0000 \u0000 Unconventional shale development requires continuous optimization to improve the Stimulated Rock Volume (SRV) created by hydraulic fracturing, which in turn maximizes the hydrocarbon recovery of wells. Whenever shale formations exhibit a geological heterogeneity, the distribution and magnitude of the associated geomechanical heterogeneity can significantly impact fracture propagation and result in fracture barriers or baffles that negatively impact the SRV. It is essential to adapt well targeting, hydraulic fracture design and well spacing to these heterogeneities to optimize the SRV. In this case study, such mechanically heterogeneous beds within the reservoir (resulting from geologic variability) were identified through core analysis and measurements. These heterogeneities did not have a clear interpretable log signature so it was difficult to locate, map, and assess their distribution across the play using well logs prior to applying the methods described in this paper.\u0000 \u0000 \u0000 \u0000 The method discussed in this paper consists of designing a machine learning predictive model that after training on 9 cored wells, was able to predict the distribution and thickness of the geomechanical heterogeneities across the play using roughly 100 vertical wells with triple combo logs.\u0000 Beyond the classic methodology of machine learning, today considered a conventional technology, this paper presents the key steps of data processing that significantly improved prediction accuracy, and focuses on explaining why most of those steps are likely to be useful for a variety of analogous geological machine learning workflows. The workflow included: 1- an original transformation of the raw logs into engineered features based on a proper understanding of the impact of the heterogeneities on the behavior of each log; 2- a decomposition of the classification model into multiple stages, to integrate geological expertise and boost some critical algorithmic elements (in particular through class imbalance correction and bias-variance optimization); 3- an advanced management of cross-validation and exploitation of genetic searching, to optimize model robustness with a relatively small input dataset.\u0000 \u0000 \u0000 \u0000 Excellent prediction accuracy based on cross-validation was confirmed by a remarkable geological/geographical consistency of the results, once prediction results were converted into maps. The continuity of deposits and orientations of the sediment supply were in line with known basin paleogeography.\u0000 This paper defines a comprehensive approach of machine learning applied to electrofacies, and beyond the direct results of the study, it highlights how data science methods benefit from in-depth integration of geological interpretation.\u0000 As mentioned earlier, this case is also a great demonstration of the capacity of Machine Learning to identify weak signals within the data, in a case where human interpretation is limited.\u0000","PeriodicalId":11061,"journal":{"name":"Day 1 Mon, November 11, 2019","volume":"70 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82284730","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":"Single Phase Retarded Acid System with Degradable Fibers Unlocks Production Potential in Tuba Formation, North Kuwait","authors":"B. Al-Enezi, Peiwu Liu, Hai Liu, K. Kanneganti, S. Aloun, Sultan Al-Harbi, A. Al-Ibrahim","doi":"10.2118/197201-ms","DOIUrl":"https://doi.org/10.2118/197201-ms","url":null,"abstract":"\u0000 A recent study showed that Tuba reservoir, a limestone-rich formation, has the highest oil in-place of all upcoming reservoirs in North Kuwait. This tight formation has three main layers - Tuba Upper (TU), Tuba Middle (TM), and Tuba Lower (TL) with several reservoir units alternating with non-pay intervals. The reservoir units contain significant proven oil reserves; however, production performance after conventional acid fracturing treatments has been historically subpar. As part of new development plan, two horizontal wells, one in TU and one in TL were drilled to evaluate the production potential of a new completion strategy and technologies.\u0000 This paper presents one such technology, a single-phase retarded acid system used as a pilot project study. In contrast with previous conventional emulsified acid systems, the single-phase retarded acid minimized tubing friction, thus enabling high pumping rates for the entire treatment. Alternating with the acid system, a viscoelastic surfactant-based leakoff control fluid system allowed the acid stages to reach deeper into the formation. To aid, degradable fiber technology was pumped in several stages to achieve near-wellbore diversion and further control leakoff into large natural fractures, thus improving the stimulated reservoir volume. These fibers are designed to completely degrade with time and temperature after the treatment. Delivery of the complex acid fracturing treatment was optimized in real time for each stage based on bottomhole pressure trend and response.\u0000 Combining a new single-phase retarded acid system with chemical diversion technology has proved to be effective in maximizing lateral coverage and etched fracture half-length. Post-treatment evaluation of TU horizontal well revealed the initial production was as much as 150% higher than offset vertical wells after conventional treatments with gelled acid and as high as 100% higher than a previous multistage horizontal well treated with emulsified acid. The TL horizontal well was just put into production recently and is showing encouraging results considering the lower reservoir quality compared to TU formation.\u0000 The success of this technique and technical combination delivered breakthrough results for this region and has engaged new interest in developing the Tuba reservoir.","PeriodicalId":11061,"journal":{"name":"Day 1 Mon, November 11, 2019","volume":"56 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84851738","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":"Sequential Failures in Incident Investigation Process Hindering Prevention of Incidents","authors":"Muhammad Tayab, S. Valappil, Vishal Shah, Takhir Azhibekov, M. Zeinati, Mohammed Al Ameri, Fatima Al-Hameli","doi":"10.2118/197163-ms","DOIUrl":"https://doi.org/10.2118/197163-ms","url":null,"abstract":"\u0000 Over the last 10 years, Oil & Gas operations have come under tremendous pressures due to increasing production demands and economic conditions, demanding higher performance and venturing into technically challenging operating conditions. Operating with aging facilities in harsh environmental conditions and higher crew turnaround, have resulted in higher number of serious incidents. Prevention of incidents remains high on the agenda of oil & gas companies and focus is placed on incident investigations to identify root causes of incidents and development of corrective actions. However, repetition of incidents with similar findings and causes have been observed, raising concerns if right root causes were identified and focused corrective actions were identified and/or implemented.\u0000 An extended analysis of over one thousand (1000) incidents was conducted to assess degree of repetition of causes and regrouping of causes to assess linkage of human factors with organizational behaviours. It was found that 31% of incidents were triggered by human errors & mistakes whilst 27% were attributed to violations. All violations were deemed as intentional & routine and further investigation was not undertaken. Management Supervion & Employees Leadership was identified a leading root cause category of incidents and this category contributed 20% of incidents followed by Work Planning (18%) and behaviour (12%). 55 % of incidents were caused by human factors and hauman factors were triggered by errors and mistakes rather than violations.\u0000 Often efforts are exerted to to influence individual's behaviour however human attitude (cognitive, emotional and commitment) is overlooked as linkage between attitude change leading to behavior change, not fully explored. However, linkage from behavior change to attitude change is much stronger. If worker consciously change their behavior, it requires re adjustment of associated attitudes to align with the new behavior. Positive reinforcement is an effective tool to influence individual's behaviour. If discipline and punishment are used to discourage unsafe behavior, the intended results are not achieved (e.g., incident or near miss are not reported for fear of sanctions).\u0000 Assessment of non-compliant behaviors (Violations, mistakes and errors) & conditions and factors influencing such behaviors are often not evaluated and focused action plans to address abilities and motivations with due consideration to isolated or systemic conditions are instrumental in preventing incicidents.","PeriodicalId":11061,"journal":{"name":"Day 1 Mon, November 11, 2019","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86763101","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":"Digitalize Asset Integrity Management by Remote Monitoring","authors":"Mohamed Sahid","doi":"10.2118/197168-ms","DOIUrl":"https://doi.org/10.2118/197168-ms","url":null,"abstract":"\u0000 \u0000 \u0000 ENSURING IMPROVED ASSET INTEGRITY by Realtime Corrosion Monitoring and Steam Trap Monitoring\u0000 Monitoring of corrosion in a process pipelines have always been of paramount importance to ensure the integrity of plant assets. Similarly, steam traps play a very important role in ensuring steam quality, thereby the integrity of critical assets in the plant. It is common observation that many of the steamtraps become non-functional over a period of time and, more importantly, dangerously go unnoticed. While these are vital in ensuring asset integrity, and need continuous monitoring, it is also a highly demanding and challenging activity in the field, and a dream of many Integrity engineers to perform such asset monitoring remotely, that too, in realtime. Many vendors have been researching on this, and focusing on devising improved technology to ease the burden on such asset monitoring.\u0000 This paper intends to touch upon these two aspects of monitoring Asset Integrity – Realtime Corrosion monitoring and Realtime Steam Trap monitoring – as implemented in ADNOC-LNG. The paper shall highlight the importance of digitalization in the Asset Integrity Management - Pipeline Corrosion and Steam Trap monitoring - by means of implementing wireless technology and making the data available in remote workstations in realtime.\u0000 Topics covered:\u0000 Corrosion Monitoring: to move ahead from the conventional Corrosion management to the Wireless Ultrasonic Thickness gauging technology\u0000 Steam Trap Monitoring: to remotely monitor the healthiness of Steam Traps with a combination acoustic and temperature instruments.\u0000 \u0000 \u0000 \u0000 Corrosion Monitoring: The installation at ADNOC-LNG covers 20 locations in OAG unit (Offshore Associated Gas unit, which has been identified as highly corrosion prone). The procedure involves installing UT sensors at the identified CMLs (Corrosion Monitoring Locations). These are easily installable onto the piping, and each sensor has a measurement footprint of about 1-2 cm2, which is similar to the manual ultrasound inspection method. The technology of ultrasound is well proven and has been used by Integrity engineers for manual inspections. These sensors employ wireless communication, and are powered by battery packs, which last through turnarounds. Doing away with the needs of power and signal cable, simplifies the installation process.\u0000 Steam trap monitoring system (20 locations identified in LNG Train-3 Utilities) also employs wireless acoustic and temperature sensors, which are installed on the steam trap piping. From the acoustics and based on the skin temperature measurements, the system identifies the health of the steam traps and determines which are Failed shut, or blow through.\u0000 \u0000 \u0000 \u0000 Corrosion Sensors: These UT sensors continue to give the wall thickness measurements of the exactly same point, over a period of time, which can help analyze the early onset of corrosion; unlike the manual UT measurements, where the repeatability and reproducibi","PeriodicalId":11061,"journal":{"name":"Day 1 Mon, November 11, 2019","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84487715","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":"Deferment of Mini Shut Down with Partial Automation of Manual Control","authors":"Abdulla Mubarak Al Dhaheri, Ahmed Khalaf","doi":"10.2118/197340-ms","DOIUrl":"https://doi.org/10.2118/197340-ms","url":null,"abstract":"\u0000 ADNOC LNG (Train 3) processes High Pressure gases from ADNOC Off shore and the gas goes through a series of processes to remove Hydrogen Sulphide & other impurities and gets dehydrated before the gases are processed to separate the various components as products. The Acid Gas Removal Unit is a hybrid arrangement of the basic Benfield Carbonate unit and Amine technologies. The Carbonate Unit, using Potassium Carbonate as the solvent, does the bulk of the Acid Gas removal from the feed gases.\u0000 Subsequent to restreaming of Train-3 after 2018 T/A, in the Acid Gas removal unit, Lean Carbonate Flash Drum level control valve 2C-LV-61 got stuck and became inoperable from DCS. Since then the level of Lean F/D 2C301 was controlled by operation of manual bypass valve in field along with frequent adjustment of Makeup water flow to Carbonate Reflux Drum 2C313 by DCS controller 2CFC0082. The valve 2C-LV-0061 could not be released for maintenance due to passing Isolation valves. To enable complete draining of the system and replacement / repair of the defective valves a mini-SD of Train 3 (minimum of 7 days) was planned in June’19. Seven days’ shut down for the sake of this repair would result in loss of production resulting in a revenue loss of US dollors35 million.\u0000 A specialist review meeting was conducted on 12th Feb and on 9th March 2019 with Operations, Process Engineering & Control Maintenance to discuss the alternative option of automating makeup water flow control (2CFC0082), with the objective of reducing daily field operations required to control carbonate flash drum level during steady state conditions, whilst also improving level control and retaining plant stability.\u0000 The new control scheme to cascade the level of Lean F/D to existing flow control 2CFC0082 was implemented vide minor DCS change MDCSC/008/19 on 21st March 2019. The Performance has been satisfactory during normal steady state operating conditions.\u0000 Based on the observations, it was recommended to, continue with Auto operation of FC0082 to control level of Lean Flash Drum during normal operation with field operator support to operate the LV61 bypass valve, in case of a programmed or unexpected upset in level of Carbonate flash drum.\u0000 Thus the Shut down was deferred successfully till the next planned turnaround opportunity resulting in an opportunity to save US dollors 35 million.\u0000 Statement of Issue: Soon after restreaming the train after Turnaround, an important control valve in the carbonate circuit of the LNG Train 3, namely 2-C-LV-0061, became inoperable while the Train was running. Attempts to isolate the valve failed due to passing isolation valves which made online repair impossible. A complete shut down of the Train to repair the defective valve would mean a revenue loss of US dollors 35 million due to loss of production (in addition to the impact of flaring).","PeriodicalId":11061,"journal":{"name":"Day 1 Mon, November 11, 2019","volume":"68 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83266216","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":"A Novel Lwd Tool Based on High-Frequency Electromagnetic Wave Used for Determining and Ranging Reservoir Boundary","authors":"Xinmiao Teng, Limin Sheng, Liancheng Zhang, Weiping Ai, Wenkai Gao, Yu Dezhou","doi":"10.2118/197309-ms","DOIUrl":"https://doi.org/10.2118/197309-ms","url":null,"abstract":"\u0000 To increase reservoir-encounter drilling ratio while horizontal directional drilling, this paper presents a novel LWD tool based on the high frequency electromagnetic wave, which can get the accurate distance between the drilling tools and reservoir boundary. While horizontal directional drilling in the reservoir, the LWD tool mentioned transmits a modulated single-frequency pulse, the pulse width is about 10ns and the central frequency is about 350MHz, by the transmitting antenna. The high frequency electromagnetic wave is reflected on the interface of the reservoir and the cap because of the dielectric difference. The reflected wave can be captured by the receiving antennas and then be processed in the designed algorithm aiding in ranging the distance of the reservoir boundary in real time. A 2.0*1.0*0.7 meters clay sand, concrete ground and a saline bag with the conductivity in 60mS/cm are designed to simulate the situations likely to be in real horizontal directional drilling operations and to evaluate the detection capability of the LWD tool in a controlled situation. Under the different conditions and distances, the measurement range of the LWD tool is about 0.7∼2.0 meters and the accuracy is less than ±3 centimeters, a high accuracy for geosteering in horizontal directional drilling, which will be greatly helpful to keep the drilling bit drilling in the optimum position of oil or gas reservoir all the time to increase the reservoir-encounter drilling ratio.","PeriodicalId":11061,"journal":{"name":"Day 1 Mon, November 11, 2019","volume":"48 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90709468","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":"Reservoir-Scale Characterisation and Prediction of Microporous Limestones. Example the Arab Formation Upper Jurassic, Onshore United Arab Emirates.","authors":"Wala bin Ishaq, Fatima Al Darmaki, N. Lucas, Mohamed Al Mansoori, Matthieu Deville de Periere, A. Foote, M. Bertouche, C. Durlet","doi":"10.2118/197248-ms","DOIUrl":"https://doi.org/10.2118/197248-ms","url":null,"abstract":"\u0000 In the onshore sector of the United Arab Emirates, the Lower Arab D Member (Kimmeridgian) typically encompasses a thick succession of rather homogeneous low-energy mid-ramp carbonate mudstones interbedded with minor storm-induced cm-scale skeletal-rich floatstones. Within these deposits, the pore volume is dominated by locally abundant matrix-hosted micropores, along with variably abundant open to partially cemented fractures, primary intraparticle macropores and rare moulds and vugs. As a result of this variably developed pore system, measured porosity varies from poor to very good, while permeability changes from extremely poor to rarely good. Detailed petrographic observations (thin-sections, SEM) carried out within six cored wells in a sour gas reservoir highlight that the variations in reservoir properties are primarily linked to the micron-scale variations in the micritic fabric. Indeed, anhedral compact micrites with coalescent intercrystalline contacts are associated with very small and poorly connected micropores, while polyhedral to subrounded micrites with facial to subpunctic intercrystalline contacts show locally well-developed micropores and therefore better reservoir potential. δ18O and δ13C isotope measurements do not discriminate both micritic fabrics, indicating a recrystallisation of the matrix within shallow burial conditions. However, bulk XRF measurements, and especially SiO2, Al2O3 and Fe2O3 content indicate that poorly porous anhedral compact micrite host more insoluble material and have been prone to a greater compaction compared to porous polyhedral micrites. Log-derived elastic properties, including Young's Modulus (YME) along with porosity data, have been used in two wells to explore the potential relationship between micritic fabric, porosity, permeability and elastic properties. With the evolution of micritic fabric from anhedral compact to polyhedral / subrounded, Young's Modulus decreases with increasing porosity, indicating a decrease in the overall stiffness of the rock. Based on these two learning wells, specific porosity and YME cut-offs have been identified to discriminate the various micrite fabrics. Those cut-offs have been successfully tested in four other wells used as a blind test for the vertical prediction of the micritic fabrics, in which accurate predictions reached up to 90%. Following these results, porosity and YME cut-offs have been used to produce the first model of the distribution of the various micritic fabrics at the field-scale. These results have a fundamental impact on how sedimentologically homogenous microporous limestones can be described and predicted at the well and field-scales, especially in the context of exploring tight carbonate plays associated with intrashelf basins.","PeriodicalId":11061,"journal":{"name":"Day 1 Mon, November 11, 2019","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-11-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90927612","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}