Day 2 Tue, November 13, 2018最新文献

{"title":"Using CHARM Modelling to Decide the use and Discharge of Surfactant at an Offshore EOR Project","authors":"Ivy Chai Ching Hsia, Nur Anisah Shafie, N. Razali, A. A. A. Manap, I. K. Salleh","doi":"10.2118/192715-MS","DOIUrl":"https://doi.org/10.2118/192715-MS","url":null,"abstract":"\u0000 The application chemicals such as surfactants for Enhanced Oil Recovery (EOR) has caught the attention of various stakeholders especially regulators and operators - raising concerns of the impact of these chemicals to the ocean when they are back-produced. The current approach in mitigating the toxicity at production is the dilution of produced fluids to a lower concentration before disposal to sea. However, how confident are we that EOR chemicals do not cause environmental impact to marine life? Due diligence conducted showed that there are no environmental regulations or guidelines in Malaysia for the application of EOR chemicals at an offshore platform. For this reason, our team refers to the strictest of regulation for chemicals' use and discharge for an offshore environment used at the North/Norwegian Sea, adopting all qualification criteria from Harmonized Ocean Chemical Notification Format (HOCNF), of the OSPAR Harmonised Mandatory Control System (HMCS), developed through the OSPAR Decision 2000/2. HOCNF ranks chemical products according to Hazard Quotient (HQ), calculated using the Chemical Hazard and Risk Management (CHARM) model. CHARM is a set of rules to determine the risk and extent of surfactant formulation's movement in the ocean - a vital decision making tool to determine if EOR chemicals are safe for use and overboard discharge. This paper describes the ‘environmental-friendliness’ of a newly developed surfactant formulation which will be applied in a Water-Alternating-Gas (WAG) operation at an offshore field in Malaysia using CHARM. First, a comprehensive review of the components of the formulation was conducted, leading to sound selection and/or synthesis of chemistries that confers good environmental properties i.e. non- or low toxicity, persistency, bioaccumulation, with high biodegradability. Next was to determine the degree of toxicity of the formulation at three trophic levels. Using the lowest acute toxicity value, we apply this value to the CHARM model to calculate the dilution of the formulation 500 m radius from the point of discharge - given the expected adsorption, application concentration, and the volume ratio between squeeze vs. produced water. Whether CHARM is exhaustive to decide if the surfactant formulation can be discharged overboard is still being debated. Many argued that it is the responsibility of the chemical manufacturer or product inventor to select or synthesize chemistries with good ecotoxicity properties in the first place. Product innovation has to be aware on new regulation(s) e.g. the banning on the use of a chemical currently used in manufacturing so that the company develops an alternative ahead of its competitors. In the operator's viewpoint, even if the model indicates that the chemical pose a low hazard, physicochemical parameters of the produced fluids has to be monitored beyond the pilot implementation period.","PeriodicalId":11208,"journal":{"name":"Day 2 Tue, November 13, 2018","volume":"457 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76335016","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":"Innovative Approach for the Salt-Related Converted-Wave Identification and Attenuation - Offshore Egypt, Mediterranean Sea, Case Study","authors":"I. Mihaljević, R. Zaki, S. Rana, M. Hegazy, O. Zdraveva","doi":"10.2118/192638-ms","DOIUrl":"https://doi.org/10.2118/192638-ms","url":null,"abstract":"\u0000 \u0000 \u0000 Abrupt and large changes in the earth properties (velocities) can cause conversion of the compressional waves to converted mode energy. Such converted waves could be recorded on the towed streamer seismic data. If they are not identified and removed early they can mislead the interpretation. In this paper, we are showing the successful application of the converted wave attenuation (CWA) workflow on the seismic data from the Mediterranean See, Offshore Egypt. Data is acquired with latest broadband technique and went through several iterations of velocity model building. The presence of the strong converted waves has threatened to undermine velocity model building and interpretation effort. The benefit of presented workflow is that it identifies and models the converted energy pre-stack pre-migration, however the subtraction is done pre-stack post-migration. Post-imaging subtraction gives improved flexibility in signal protection and improvements in the S/N ratio, especially in the areas where the separation of the converted more and compressional energy is small. Presented workflow is universally applicable to any areas where the converted modes occur.\u0000","PeriodicalId":11208,"journal":{"name":"Day 2 Tue, November 13, 2018","volume":"2019 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87857648","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":"Modeling Rate of Penetration for Deviated Wells Using Artificial Neural Network","authors":"A. Abbas, S. Rushdi, M. Alsaba","doi":"10.2118/192875-MS","DOIUrl":"https://doi.org/10.2118/192875-MS","url":null,"abstract":"\u0000 The advanced technology has made directional drilling widely used to enhance the production of mature fields. The rate of penetration (ROP) contributes strongly towards the cost of drilling operations, where achieving higher ROP leads to substantial cost saving. The main objective of this study is to develop a model that predicts the ROP for deviated wells using artificial neural networks (ANNs).\u0000 The model was developed based on the most critical variables affecting ROP using ANNs. In addition to the azimuth and inclination of the well trajectory, the controllable drilling parameters, unconfined compressive strength (UCS), pore pressure, and in-situ stresses of the studied area were included as inputs. 1D Mechanical earth modeling (1D-MEM) data, geophysical logs, daily drilling reports, and mud logs (master logs) of deviated wells drilled in Zubair field located in Southern Iraq were used to develop the ANN model.\u0000 The results displayed that the ANN’s outputs are close to the measured field data. The correlation coefficient (R) and average absolute percentage error (AAPE) were over 0.91 and 8.3%, respectively, for the training dataset. For testing data, the developed model achieved a reasonable correlation coefficient (R) of 0.89 and average absolute percentage error (AAPE) of 9.6%. Unlike previous studies, this paper investigates the effect of well trajectory’s (azimuth and inclination) and their influence on the ROP for deviated wells. The major advantage of the present study is calculating approximately the drilling time of the deviated well and eventually reducing the drilling cost for future neighboring wells.","PeriodicalId":11208,"journal":{"name":"Day 2 Tue, November 13, 2018","volume":"112 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77024924","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":"Use of Exogenous Bacteria to Improve the Bioremediation Process in the Caracara Field Colombia","authors":"J. Molano","doi":"10.2118/193267-MS","DOIUrl":"https://doi.org/10.2118/193267-MS","url":null,"abstract":"\u0000 CEPSA Colombia developed an improved technique for bioremediation; implemented since 2012 in the onshore Caracara field. This optimizes the processes of biostimulation and bioaugmentation by introducing exogenous bacteria, with efficiency (reduction of grease and oil) close to 90%.\u0000 The technique exceeds the performance of other published methods, as it has been used successfully for the biotreatment of soils and fluids impregnated with hydrocarbons at concentrations of fats and oil of up to 20 ± 2 wt%, equivalent to 200,000 ± 20,000 ppm (mg carbon/kg soil). Previous studies have suggested that oily sludges only with concentrations of fats and oils below approximately half that level can be bioremediated to achieve a compliance criterion standard close to 1 wt% as established in Chapter III of Louisiana Protocol 29-B and commonly adopted as an oil industry norm.\u0000 It is an ‘ex situ’ process since although applied at the field location the sludge is first collected and stored prior to batch biotreatment. The technique is most applicable to oily sludges that do not have an excessive asphaltene and resins content: asphaltenes are not biodegradable by microorganisms, given their structural complexity and resistance to the enzymatic attack produced by bacteria.\u0000 Our successful field pilot has been expanded to an industrial scale and has over a six-year period effectively treated the environmental liability of sludge ponds of approximately 12,000 m3 inherited when CEPSA assumed its interest in the Caracara field. Operations continue, treating ongoing generation of oily waste at an estimated cost saving of 54% relative to the treatment and transport costs of contracting an external bioremediation service provider.\u0000 We have developed simple criteria to screen the suitability of oily sludges for our process, which is simple, easy to implement and cost-effective, as it relies on bacteria generated from waste products readily available in the field at no cost. It should be applicable to other fields with similar environmental conditions.","PeriodicalId":11208,"journal":{"name":"Day 2 Tue, November 13, 2018","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88189934","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":"Process Safety in Design Verification in Operational Phase for Onshore Gas Production Plant","authors":"Omar Mohammed Abdelsalam","doi":"10.2118/193076-ms","DOIUrl":"https://doi.org/10.2118/193076-ms","url":null,"abstract":"\u0000 It is a mandatory company requirement for all offshore and onshore assets to secure the documentation and demonstration of process safety in design (PSID). The common way to conduct the PSID is to apply it within the \"Design phase\" and after the \"Execute phase\" to remove or minimize hazards and identify areas of process design that warrant specific focus. In this paper, we will show a case of implementing the PSID verification on an onshore gas production plant during operation phase which is different from the main approach and way of verification during earlier stages of project execution.\u0000 Verification is intended to confirm that the detailed documentation and calculations supporting the requirements of the Process Engineering Process Safety Design Standard have been correctly performed.\u0000 In broad terms the objective of the verification in the \"Operation phase\" was;To confirm that the extent of documentation available meets the minimum requirements of the company standards.To confirm that adequate layers of protection are being provided throughout the process to reduce risks to ALARP (As Low As Reasonably Practicable).To confirm that all Blowdown systems and relief valve calculations have been correctly conducted and appropriate relief cases and basis have been used.To confirm that HAZOP/HAZID has been conducted in a reasonable manner and the actions have been closed out.To confirm that layers of protection analysis \"LOPA\" for all site safety instrumented functions (SIFs) as part of Safety Integrated Levels (SIL) assessment have been assessed and verified.To confirm that specification breaks have been properly located and HP/LP interfaces correctly designed.To confirm that the philosophies are complete, adequate and implemented.To confirm that process safety is being assured for the project and to identify and record any failings or flaws in approach, detailed calculations or design that require rectification.\u0000 The design contractor produced a Process Safety Dossier which contained sections as following:Design PhilosophiesRelief and Blowdown DesignHP/LP InterfacesLOPAHAZOP/HAZID verification\u0000 The outcome of the verification on the existing gas production plant was a list of findings categorized – from 1 to 4 – according to their priority from safety point of view. We ensured closure of the actions starting from code 1 and code 2 in a tight time frame to avoid any risk to be released.","PeriodicalId":11208,"journal":{"name":"Day 2 Tue, November 13, 2018","volume":"02 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86107792","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":"Application of a New Concept for Enhanced Well Integrity Evaluation in Unconventional Completions with Fiberglass Casings in Kuwait","authors":"Y. Abugreen, R. Kalyanraman, M. Al-Hajeri, S. Raturi, Abdullah Hamadah, F. AL-Qahtani","doi":"10.2118/193111-MS","DOIUrl":"https://doi.org/10.2118/193111-MS","url":null,"abstract":"\u0000 The cement bond evaluation of wells completed with fiberglass casings has always been a challenge due to the very large difference in the acoustic behavior of fiberglass with respect to steel. This problem was faced in Kuwait when ultrasonic image logs were recorded for some wells completed with fiberglass casings that gave highly erratic readings and posed significant challenges with interpretation when applying the conventional methods. It was critical to field development engineers to have the precise status of the cement bond around fiber casings to ensure integrity of casing from encroachment of formation fluids in the zone of interest. This, in turn, required that cement bond logs do accurately and precisely evaluate the cement integrity. The logging company along with drilling engineers resolved the challenge of interpretation innovatively by an integrated approach of ultrasonic and sonic data. The approach used a recently introduced platform to develop a new concept of data processing in which high-accuracy interpretation of the cement bond behind fiberglass was made possible.\u0000 As has been observed through field and laboratory experiments, the conventional ultrasonic technique applicable to carbon steel pipes has been proven to be invalid in fiberglass tubulars because the velocity and acoustic impedance of fiberglass are much lower than steel; therefore, there is no resonance in fiberglass. A new method and interpretation tool was developed and applied to raw data to build on parameters specific to the fiberglass samples used in Kuwait through surface tests to identify the acoustic properties of fiberglass: acoustic impedance, attenuation factor, and velocity.\u0000 Standardized processing parameters were established for consistency and accuracy to determine the actual pipe thickness, radius and cement acoustic impedance from ultrasonic measurements in many wells. The resulting logs from the new method were found to be satisfactory by field development and they were then applied to earlier drilled wells to validate the results. The advanced platform used for data processing and integration has provided a reference interpretation prototype of log response in fiberglass casings in different scenarios to accurately determine whether cement bond is poor, good, or non-existing. A further investigation of ultrasonic late waveform arrivals could elaborate unique information on casing standoff and centration inside the wellbore. A reasonable casing integrity evaluation was also feasible from the new method resulting in good estimate of valid pipe thickness and acoustic impedance.\u0000 This paper illustrates the application and evolution of the new method, which enables advanced data processing and integration to provide robust images even beyond cement and pipe integrity. It has been implemented in many wells, and it has provided a significant improvement in quality of logging results in fiberglass casing wells. The new interpretation model can be succ","PeriodicalId":11208,"journal":{"name":"Day 2 Tue, November 13, 2018","volume":"158 12 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83232181","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":"Optimal Thermowell Design Improves Plant Safety & Integrity","authors":"S. Ganesan","doi":"10.2118/192658-MS","DOIUrl":"https://doi.org/10.2118/192658-MS","url":null,"abstract":"\u0000 The intent of this paper is to highlight the enhancements in latest Performance Test Codes (ASME PTC 19.3), evaluate the causes of failures occurred in thermowells and define the importance of optimal thermowell design.\u0000 Failure of a thermowell can have catastrophic consequences, which results in loss of containment and affects the plant safety, integrity & profitability. Hence, an efficient design, the proper selection and the operation within limits are essential to achieve 100% HSE and ensure a fit-for-future service.","PeriodicalId":11208,"journal":{"name":"Day 2 Tue, November 13, 2018","volume":"20 6","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91433784","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":"Significant Increases in Turnaround Maintenance Performance and Safety through Powerful Digital Integration","authors":"Michel M. Tol","doi":"10.2118/192958-MS","DOIUrl":"https://doi.org/10.2118/192958-MS","url":null,"abstract":"\u0000 More and more leading companies are moving to digital systems to support their operations, maintenance and turnarounds. This marks huge progress and sees impressive results: incidents and injuries decrease, risk becomes more understandable, and processes streamline and simplify. But if the information used within these digital systems is not connected or up to date, the concept simply does not work effectively.\u0000 Collaborating closely with major industry players such as Shell, BP, RasGas, Borouge, and others, eVision Software developed bespoke daily maintenance and turnaround management solutions, which address and mitigate many common turnaround and maintenance challenges. The enterprise-ready tool combines powerful Permit to Work, Risk Assessment, Isolation management and advanced (Mobile) visualisations, and integrates these into the client ecosystem. This study pertains to a major derivatives manufacturer in the UAE, in which a platform was implemented to help achieve ambitious hands on tool time increases during their planned shutdown.\u0000 Integration gets the most out of existing client data and solutions. From preparing digital permits and risk assessments in eVision's software using up-to-date equipment and location information from Maintenance Management Systems (MMS); to creating context-sensitive work execution packs linked to Oracle Primavera, which can be mass signed, enabling continuous scheduling optimisation; to effective and efficient maintenance execution empowered by mobile tools for front-line crew; to monitoring real-time data through connected dashboards. Data and systems are connected, information is shared in real time, reducing Turnaround time and improving capacity planning and Hands on Tool Time, thereby decreasing the number of contractors required for the next shutdown. This continuous feedback loop further enables the client to take lessons learned and improve their next turnaround, getting maximum return out of their digital solutions.\u0000 By taking a platform approach to shutdown preparation and execution, and utilising the vast amount of data available across systems throughout the asset, challenges could be met head-on and mitigated, without large-scale changes to infrastructure or methodology. Creating a synergy between existing systems, new solutions and effective and improved procedures allowed staff to focus on what really matters: quick and safe turnarounds. During the 2016 planned shutdown, a core goal was to increase the HoTT of staff and contractors by a minimum of 7%. eVision was able to improve HoTT by more than 17% overall, by tackling key challenges, such as permit cycle duration, work instruction time, and vast reduction of indirect productive hours. By implementing the integrated software platform, the workforce was able to more effectively utilise their time on plant.","PeriodicalId":11208,"journal":{"name":"Day 2 Tue, November 13, 2018","volume":"181 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83420806","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":"Preserving Great Discoveries by Using Non-Damaging Killing Fluid During the Temporary Abandonment of HPHT Exploratory Wells","authors":"A. Al-Ibrahim, Haifa Al-Bader, Packirisamy Subban, Vidya Sagar Duggirala, M. Ayyavoo","doi":"10.2118/192670-MS","DOIUrl":"https://doi.org/10.2118/192670-MS","url":null,"abstract":"\u0000 \u0000 \u0000 Objective of this paper is to present the successful method applied to eliminate the damage caused by mud invasion during killing operation after successful testing of newly discovered reservoirs using Drill Stim Test (DST) and before running the completion.\u0000 \u0000 \u0000 \u0000 DST is normally used during testing the exploratory wells to record the downhole pressure and temperature and to collect downhole samples. After a successful well testing and proving the hydrocarbon potential, the test is called off and the well is usually killed with mud in order to retrieve the DST and run the completion. Heavy oil based mud (OBM) is normally used during killing HPHT wells, which causes severe damage to the treated/stimulated zone. After running the completion, the well is activated by displacing the killing mud with diesel using coiled tubing (CT). In most cases, the wells showed lower productivity after the completion due to the damage caused by mud invasion and barite settlement.\u0000 In order to overcome this serious issue, non-damaging killing fluid with Calcium Carbonate (CaCO3) pill was used in several exploratory wells. The pill causes a temporary barrier between the perforated intervals and the killing fluid (OBM) to prevent the mud invasion to the discovered reservoir. The CaCo3 pill is an acid soluble material, which can be easily dissolved with Hydrochloric acid (HCl).\u0000 After killing the well using OBM with CaCO3 pill, retrieving the DST and running the completion, the well is normally activated by displacing the killing fluid with diesel then spotting and squeezing 15% HCl against the perforated intervals. Finally, the well is flowed back for cleaning and flow measurement to confirm that the discovered reservoir is preserved.\u0000 \u0000 \u0000 \u0000 Excessive Losses of mud into the stimulated/discovered reservoir has always been a major concern during well completion operations since it leads to massive formation damage, which is difficult to be stimulated. Successful implementation of this method using CaCO3 pill in HPHT discovered reservoir has eliminated the mud invasion into the treated zone. During killing process, it was observed that the mud losses were significantly reduced by using fine to medium grains of CaCO3 in the pill. The flow back after acid wash has clearly showed similar productivity to the initial testing results prior killing. Many discovered wells were successfully preserved after treating them with small quantity of acid wash. Field application of this method in more than 10 deep HPHT exploratory wells has preserved them for future production.\u0000 \u0000 \u0000 \u0000 Using the non-damaging killing fluid with CaCO3 pill for the future exploratory wells, where the DST is mandatory, will eliminate any formation damage to the discovered reservoirs with good hydrocarbon potential which will preserve the well productivity after running the completion.\u0000","PeriodicalId":11208,"journal":{"name":"Day 2 Tue, November 13, 2018","volume":"19 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88243650","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":"Asset Management of Wells and Facilities Through Integration of Monitoring and Geomechanical Modeling for a Field with Active Subsidence in Sultanate of Oman","authors":"S. Mahajan, J. Stammeijer, H. Mukhaini, S. Azri, R. Rahmoune, M. Aamri, Ikhsan Tarmizi","doi":"10.2118/192724-MS","DOIUrl":"https://doi.org/10.2118/192724-MS","url":null,"abstract":"\u0000 One of the PDO's largest producing fields in Oman consists of three stacked reservoir formations, two of which are currently producing while deeper reservoirs are being considered for development. The shallowest reservoir (~ 900 m depth) is a highly compacting carbonate gas reservoir under depletion, whereas the intermediate reservoir Shuaiba is an oil-bearing reservoir under water flood. The deeper reservoirs are oil and gas bearing located in the Sudair and Khuff formations.\u0000 Interpretation of 3D seismic data shows a major NE/SW and NW/SE fault system in all 3 reservoirs. Depletion in the shallow gas reservoir, which exhibits pore collapsing response on depletion, has induced surface subsidence which is active and expected to reach about 2.4 m at the end of field life. Subsurface deformations and induced stress changes have resulted in subset of the faults (NE/SW) to reactivate, causing seismic tremors, occasionally felt at surface.\u0000 Ongoing surface subsidence has resulted in some damage to surface facilities and subsurface well integrity issues. Furthermore, fault reactivation and/or loss of well integrity may induce leakage pathways for reservoir fluids to cross flow between reservoirs or to shallow aquifers. PDO has implemented an extensive monitoring program supported by parallel 3D geomechanical modeling studies, to manage ongoing field development whist mitigating the risks.\u0000 Extensive monitoring efforts using a variety of techniques are in place since 1999. Frequent InSAR satellite data measures surface subsidence with such high accuracy and resolution that local zones of higher deformation can be reliably identified and flagged. Continuous GPS data acquisition in a few places throughout the field allows for detailed temporal assessment of subsidence and forms the basis for predictions of total subsidence at end of field life. Periodic in-well compaction monitoring data provides insights in elastic and non-elastic deformation at reservoir layer scale, which is compared against core compressibility data. Continuous microseismic monitoring in a dozen or more observation wells highlights geomechanically active faults in the main reservoir, overburden and underburden, thereby identifying potential risk zones on a near-24/7 basis.\u0000 All of this data is used both for well and facilities management, and for providing calibration data for geomechanical models. Results provide clarity on future surface subsidence and differential settlement, which helps to identify facilities with potential risk. The project teams are provided with reliable predictions of surface subsidence throughout the field to ensure the current design tolerance is adequate for integrity of the facilities until the end of field life. This paper presents modeling workflow and calibration with monitoring data related to the geomechanical assessment.","PeriodicalId":11208,"journal":{"name":"Day 2 Tue, November 13, 2018","volume":"33 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85487637","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}