The session will cover an area of growing interest, given increasing concern about wellbore integrity and well control. As with other MPD systems, SMD technology offers early detection of influxes (kicks) and minimizes downhole losses to weak subsurface formations. This paper describes a number of system enhancements, including the ability to display and analyze not only the critical parameters of drilling hydraulics but also other information that allows different perspectives in considering the closed-loop system. The paper demonstrates the successful application of advanced automated managed-pressure-drilling (MPD) technologies on the Dover well close to Fort McMurray, Alberta, Canada. The development of the Kanowit field offshore Sarawak, Malaysia, requires the drilling of two subsea development wells with a semisubmersible rig.
Africa (Sub-Sahara) Shell has initiated a two-well drilling program in blocks 1 and 4 of the Mafia Deep basin offshore Tanzania. Drilling is taking place in water depths of up to 7,545 ft, with the company and its joint-venture partners Pavilion Energy and Ophir Energy investing almost USD 80 million in the program. The two wells will meet the remaining requirements in the exploration licenses issued by the Tanzanian Ministry of Energy and Minerals. Asia Pacific Petronas has begun gas production from the world's first floating liquefied natural gas (FLNG) facility, the PFLNG SATU, at the Kanowit field offshore Malaysia's Sarawak state. The first-gas milestone marked the onset of commissioning and startup for the FLNG facility, preceding commercial production and initial cargo shipment. The facility is fitted with an external turret for operating in water depths of 229 ft to 656 ft. It will extract gas through a flexible subsea pipeline for the liquefaction, production, storage, and offloading of LNG at the field.
Mendes Sales, Ivan (Petrobras) | Dantas Sitonio guedes, Jonas (Petrobras) | Alexandre Martinello, Isac (Petrobras) | Couto Lemgruber Kropf, Talles (Petrobras) | Mesquita Caetano, Leonardo (Petrobras) | Alonso Fernandes, Andre (Petrobras) | Loures Sa, Lucas (Petrobras)
MPD techniques have being applied to drill zones with major fluid losses or narrow operational window. Nevertheless, subsequent operations are not yet at the same stage of development: Wireline logging, running casing and cementing are still challenging and need further development when it comes to DP rigs. Therefore, after drilling a well with hydrostatically underbalanced fluid and surface backpressure, it is necessary to replace the drilling fluid in order to continue the operations. Although, in nearly all MPD wells it is possible to do this, the major challenges are zones with absent drilling window and severe losses where PMCD technique is required. In these cases, it is not possible to use overbalanced drilling fluid. This paper presents a solution for wireline logging while using MPD techniques on DP rigs with underbalanced drilling fluid. At first, it shows the planning phase and its discussion, then the execution phase with its difficulties.
Radzuan, Nurul Asyikin M. (PETRONAS) | Salleh, Nurfarah Izwana (PETRONAS) | Chandrakant, Ashvin Avalani (PETRONAS) | Rusman, Liyana (PETRONAS) | Zamanuri, Kautsar (PETRONAS) | Bakar, Azfar Israa Abu (PETRONAS) | Yip, Pui Mun (PETRONAS) | Jamaluddin, M. Helmi (PETRONAS) | Ghonim, Elsayed Ouda (PETRONAS) | Nambiar, Vijay (Novomet) | Alexander, Euan (Artificial Lift Solutions)
Following the first pilot success of the truly rigless 3-1/2" tubing cable deployed ESP (TTESP-CD in offshore field of Sarawak Basin, PETRONAS has taken steps to further advance in the technology development and application through more replications within Sarawak and Malay Basin. PETRONAS had been looking into a strong business case for the TTESP-CD technology for a wider application throughout Malaysia region by looking at fields with strong/moderate water drive and low bubble point pressure besides having other limitations on the platform including the facilities reliability issues. TTESP-CD are to be applied widely in Malaysia with more flexibilities in design and improvement towards the subsurface equipment, installation equipment and procedures. With the challenges in the existing completion and production requirement for replications, based on the lesson learnt from the pilot implementation, multiple improvements to the system have been done including; 1) A High Rate Slim Pump with Flexible Application 2) Alignment Tool for Cable Hanger Orientation. With this in place, more opportunities identified for the candidate selection which improve the installation philosophy specifically in dual string applications and enhance the efficiency in installation procedures. Case studies of TTESP-CD replications in Malay & Sarawak Basin for Field T, Field B and Field P presenting the best case for TTESP-CD application with improvement to design, equipment and application. These will bring additional value to PETRONAS with estimated production gain of 1.5 KBD and up to 1.2 MMSTB reserves to be monetized with additional value saving of up to RM 6 Mill. Besides the subsurface challenges, aging offshore assets brings a lot of challenges, especially on the space availability, structural integrity, power availability and distribution, instrumentation and data transmission. This requires an integrated approach from multiple disciplines in delivering the studies as per required within the targeted timeframe.
Bashir, Yasir (Universiti Teknologi PETRONAS) | Babasafari, Amir Abbas (Universiti Teknologi PETRONAS) | Biswas, Ajay (Universiti Teknologi PETRONAS) | Hamidi, Rositi (Universiti Teknologi PETRONAS) | Moussavi Alashloo, Seyed Yaser (Universiti Teknologi PETRONAS) | Tariq Janjuah, Hammad (American University of Beirut) | Prasad Ghosh, Deva (Universiti Teknologi PETRONAS) | Weng Sum, Chow (Universiti Teknologi PETRONAS)
A majority of remaining proven Oil & Gas reserves is contained by Carbonate reservoir, and much more complicated to explore as imaging of the Carbonate rocks is poor. In case of Carbonate data, seismic diffraction imaging has contributed to an enhancement in the quality of seismic but there is still lack of understanding the lithology and impedance contrast which can be defined by the seismic inversion. In contrast, to the conventional process, an integration of seismic inversion methods are necessary to understand the lithology and include the full band of frequency in our initial model to incorporate and detail study about the basin for prospect evaluation. In this paper, an integrated approch is developed for better deleniation of subsurface structure and lithologies. Seismic post stack inversion technique is applied to the Carbonate field to study Electroficies and lithofacies of subsurface strata for better and detail study of the reservoir.
Kashim, Muhammad Zuhaili (PETRONAS) | Giwelli, Ausama (CSIRO) | Clennell, Ben (CSIRO) | Esteban, Lionel (CSIRO) | Noble, Ryan (CSIRO) | Vialle, Stephanie (Curtin University) | Ghasemiziarani, Mohsen (Curtin University) | Saedi, Ali (Curtin University) | Md Shah, Sahriza Salwani (PETRONAS) | M Ibrahim, Jamal Mohamad (PETRONAS)
In line with PETRONAS commitment to monetize high CO2 content gas field in Malaysia, C Field which is a carbonate gas field located in East Malaysia's waters with approximately 70% of CO2 becomes main target for development because of its technical and economic feasibility. Injectivity has been determined as one of the key parameters that determine the success of CO2 storage in field operations. In order to characterize the CO2 injecitivity behavior in C Field, long duration coreflooding experiments has been conducted on two representative core samples under reservoir conditions. The first set of coreflooding test has been conducted on gas zone sample and another one is on aquifer sample. Two important approach has been applied in the experiment in which the first one is where the base rate is established after each incremental stage and the second one is the pre-equilibration of carbonated brine with standard minerals based on the percentage of core mineralogy before saturating the core with aquifer brine to mimic the insitu geochemical conditions of the reservoir. Pre- and post-flooding characterization was conducted using Routine Core Analysis (RCA), X-Ray CT-scan, Nuclear Magnetic Resonance (NMR) and Inductive Coupled Plasma (ICP) to examine the porosity-permeability changes, pore size alterations and the geochemical processes that might take place during CO2 flooding. Based on the differential pressure data, it showed no clear indication of formation damage even after injection of large CO2 pore volume. Pre and post-flooding characterization supported the findings where minor dissolution/precipitation is observed. Overall intrepretation indicates that the critical flowrate is not yet reached for both samples within the maximum rates applied.
Brownfield in Balingian and Baram Delta have handful of idle wells and well to be abandoned in their inventories. The project aims to reduce the idle well inventories and support production gain through monetizing behind casing opportunities. The target is to appraise and develop LRLC potentials with lower cost of appraisals. This will maximize full field potentials before abandonment and leads to future development of LRLC opportunities as conventional reservoir becomes more difficult to develop.
The idle well inventory has grew up due to problem in production (increase water cut, HGOR) and well problems (sand, fish). An order has been introduced to reduce the idle well list up to 50%. Additionally, in the past, the LRLC intervals were often ignored and considered as water-wet sands due to high water saturation or as tight sands. These intervals, that contain significant reserves, are recognized in many technical papers explaining its identification and evaluation techniques from well-data (logs and samples/cores). The scope of the project is to rejuvenate the idle wells by add-perf LRLC reservoirs.
It is impossible to achieve the target without the presence of proper and improved LRLC BCO evaluation process, thus an integrated workflow approach (between Petrophysicist, Reservoir Engineer, Production Technologist, Asset manager & Well Intervention group) has been developed and applied in the project. A new evaluation tools had also been developed called REM (Resolution Enhanced Modelling) in order to improve the log properties of LRLC reservoirs so that the data obtained from old conventional tools can still be used to evaluate LRLC reservoir. Although LRLC is termed UNSEEN, the risk is reduced by proper understanding of hydrocarbon column and sand development.
To date, 7 fields are already benefitted from this approach. Field A LRLC reservoir for example has tripled the hydrocarbon saturation, and net to gross has improved to 20% using REM compare to 5% without REM. The other 6 fields are also gaining the same increase in the properties. This has resulted in a cumulative potential of 4.4 MMstb of reserves addition and ~11 KBopd potential gain. As a result, a better and attractive BCO proposals can be generated from LRLC opportunities. The exercise will provide the company with cheaper options of appraising and developing LRLC reservoir while reducing the idle wells. There is no better way of understanding LRLC reservoir; as no tools can identify & quantify it yet, rather from the actual production.
Hamidi, Rosita (Centre of Seismic Imaging and Hydrocarbon Prediction, Universiti Teknologi Petronas) | Ghosh, Deva (Centre of Seismic Imaging and Hydrocarbon Prediction, Universiti Teknologi Petronas)
Fault and fracture study has a great importance in hydrocarbon prospect exploration and development. Consequently, there have been lots of efforts to analyze the existence and extent of faults in subsurface layers using different methods and tools available to geoscientists; among which the seismic attributes have been proven to be efficient in detecting areas affected by faults and fractures. Seismic attributes help interpreters to highlight details focusing on the geological features of interest in seismic data. However, there are some limitations in the performance of these tools, as the algorithms are dependent on the seismic survey parameters, quality of the data and its existing patterns, and geology of the study area. Consequently, new strategies and algorithms are needed to improve the information obtained from the calculated attributes.
In this study, fault and fracture damage zone analysis is done on three – dimensional seismic data from Sarawak basin in Malaysia. Commonly used seismic attributes to detect such features including variance, dip – magnitude, curvature, and gradient – magnitude are applied. Next, spectral analysis, as a tool to identify events with different frequency content is used which can detect the patterns related to faulting and fracturing of the subsurface layers. The proposed method in this work is to examine the attributes’ performance on spectrally decomposed seismic cubes to unmask the details present at different frequencies. Accordingly, the seismic attributes are applied on the selected cubes, and the color blended cubes of the outputs are evaluated. As the results show, the new strategy reveals more detailed information that already exist in seismic data but cannot be distinguished because they are concealed in the full band seismic cube. Comparing each pair of conventional vs. spectral assisted attributes shows enhancement of the results (more details and better resolution) in all evaluated seismic attributes with the proposed method.
Nik Kamaruddin, Nik M Fadhlan (Petroliam Nasional Berhad) | Teng, Kevin Ging Ern (Petroliam Nasional Berhad) | Musa, Ikhwanul Hafizi (Petroliam Nasional Berhad) | Tan, Chee Phuat (Petroliam Nasional Berhad)
This paper presents a study on the risk associated with CO2 injection in geological storage and fault reactivation through a comprehensive workflow for determining the feasibility of CO2 storage campaign in carbonate reservoir in Malaysia. The study includes constructing a 4-D coupled reservoir geomechanical model and developing a workflow that can be used to evaluate geomechanics risks associated with carbon capture and storage (CCS) by outlining results and findings that drive key decisions in the planning of CCS strategy.
The workflows aims to better delineate and enumerate the risks with CCS as it constructing and calibrating single well models by corroborating numerous inputs including stringent laboratory testing data and drilling analysis, and combining with structural model and reservoir model to create a field wide 4-D geomechanical model using advanced time lapsed geomechanics simulation. Coupled simulations with the dynamic reservoir model provided predictions of the fault stability by considering fault deformation. The paper further highlights the geomechanics evaluation consideration (economics and engineering trade-off) in designing maximum safe injection pressure for CO2 sequestration program.
The results of the study show fault condition subjected to different time-steps of the coupled simulation during depletion and injection. At each time-step, the development of plastic shear strain and absolute displacement are plotted and risks associated with the change in reservoir pressure are assessed and quantified. Different injection plans are modelled to determine the impact on final storage capacity, long term fluid containment and upper safe injection limit to avoid breaching the caprock.
The study offers the utilization of the latest techniques in 4-D coupled geomechanical modelling which reduced the study time and cost significantly, making it affordable for in-time solution for decision making. The paper also aims to encourage the consideration of the applied novel workflow involved in CCS strategye valuation focusing on risk assessment which ultimately will affect reservoir maximum safe injection limit, capacity, long term storage safety, and monitoring program to mitigate potential geohazard leakage.
Nuclear magnetic resonance (NMR) T2 spin-spin relaxation is a well-established technique in petrophysics labs for quantifying bound/free water and pore-size distribution of reservoir rocks. The method has also been used to measure oil and water saturations, and to characterize wettability alterations for oil/water/rock systems. The T2 relaxation distribution measured by hydrogen NMR is the sum of contributions from both oil and water in the core. It is therefore necessary to separate the T2 signals of oil from water. Since deuterium oxide (D2O) does not have a NMR signal at the resonance frequency for hydrogen, brine made with D2O is commonly used as the aqueous phase to determine the oil saturation from NMR.
The objective of this work was twofold: (1) to validate the oil saturations in the core with NMR T2 relaxation at connate water saturation (before and after aging) and residual oil saturation after waterflooding; and (2) to investigate the potential hydrogen-deuterium (H-D) ion exchange between rock minerals and D2O. Berea sandstone cores were used along with the crude oil from one of the fields in the Sarawak Basin, Malaysia. The aqueous phase was a synthetic brine made with either deionized water or D2O.
Two cores containing the crude oil with D2O brine as the connate (or initial) water were aged at 75eC for up to 65 days. During the aging period, the cores were scanned three times for T2 measurements. The measured T2 volumes (supposedly a measure of the oil volume) of the two cores kept increasing as the aging time increased. However, mass balance indicated that the oil saturation was the same before and after aging. The inconsistent oil saturation measured by NMR indicated that there was H-D ion exchange between the rock minerals and D2O. The cores were then flooded with the fresh D2O brine, after which the residual oil from NMR agreed with that from mass balance, indicating that the fresh D2O had replaced the connate D2O brine affected by H-D ion exchange.
Additionally, two cores fully saturated with D2O brine were also measured by NMR before and after aging at 75°C, again confirming the H-D ion exchange between the rock minerals and D2O. Finally, the mixture of the crude oil and D2O was measured by NMR before and after aging at 75°C, indicating that the interactions between the crude oil and D2O increased the T2 relaxation time. The total T2 volume was not affected.
This work provides evidence of H-D ion exchange between rock minerals and D2O at elevated temperature. It is recommended that such interactions between the rock minerals and D2O brine be considered for related tests, especially when elevated temperature is involved.