Mahaldar, S. (Petroleum Development Oman) | Mandhari, S. (Petroleum Development Oman) | Jorgensen, W. (Petroleum Development Oman) | Busaidi, H. (Petroleum Development Oman) | Saadi, H. (Petroleum Development Oman) | Yaarubi, A. H. (Schlumberger Middle East SA)
PDO has a large portfolio of mature Gharif fields with significant hydrocarbon potential to be unlocked by efficient well and reservoir management (WRM). In 2016, focussed surveillance on Closed-in Wells (CIW) in a mature PDO South Gharif field, highlighted significant bypassed oil opportunity in Low Resistivity Pay (LoRP) reservoir –"C". Presence of conductive minerals and different clays in the LoRP sands, led to a pessimistic assessment of resistivity based hydrocarbon saturation. As such, histrocially, these oil bearing sands were not perforated. LoRP was production tested in 2 CIW & 3 New Oil (NO) wells in 2015, doubling field's net oil production (
Current inventory of high water cut (>95%) and high sand producing oil producers are being converted to dedicated LoRP producers on opportunity basis. This has reduced the frequency of expensive well workovers. Quick screening of LoRP has been initiated for all PDO South fields. Initial results show that similar bypassed oil opportunities exist in other mature brown PDO South fields as well. Broadly speaking, such bypassed oil opportunities can be attributed to one of the following subsurface mechanisms at play i.e. presence of thin sand- shale intercalations which are not vertically resolved on wireline logs, presence of condutive minerals e.g. pyrites or clays and high irreducible water saturation in microporous rocks.
With the current low oil prices, re-exploration of mature fields by interpreting and maturing low resistivity pay reservoirs, presents an attractive business proposition.
Abu Butabul Field is located within onshore Oman Block 60 in the Western region of the Central Oman Desert (Figure 1). Gas-condensate was discovered in the field in 1998. The main reservoir is the Cambro-Ordovician clastic Barik formation, which is buried over 4200 m below sea level with very low porosity and permeability. Wellbore instability related drilling problems were encountered while drilling most of the appraisal wells in the field. The problems were mainly in the shallower Natih and Nahr Umr formations, Gharif formation and deeper Safiq, Ghudun and Mabrouk formations. A geomechanical modeling study was conducted in the field to understand the causes of the wellbore instability problems and to provide recommendations for drilling new wells.
Data from nine wells were analyzed and used for the construction of 1-D mechanical earth models. Rock mechanical testing data on core samples and pressure and stress memasurement were integrated in the models. Wellbore stability analysis of those wells provided insight into the causes of the wellbore instability problems. To predict wellbore stability at any location in the field more efficiently and capturing the lateral formation property variation as indicated by the seismic data, a 3-D geomechanical model was constructed and subsequently used for predicting wellbore stability for new wells to be drilled in the field and hydraulic fracturing pressures for fracturing stimulation of horizontal wells.
This paper describes the process of constructing the 1-D mechanical earth models, performing wellbore stability analysis for the appraisal wells, , Integeration of 3D seismic Inversion, constructing the 3-D geomechanical model, predicting wellbore stability for new wells using data contained in the 3-D model and post-drill wellbore stability analysis of the planned wells.
Al Hammadi, Ibrahim Thani (Abu Dhabi Co. Onshore Oil Opn.) | Aly, Samir Handak (Abu Dhabi Co. Onshore Oil Opn.) | Khan, Muhammad Navaid (Schlumberger) | Gurses, Hakan (Schlumberger Middle East SA) | Baslaib, Abdullah
Oil and Gas industry began to take attentiveness in developing Multi Phase Flow Meters (MPFM) in the early 1980s as the remote data access and improved performance with more compact mobile testing systems were the key features of the required technology. MPFMs were initially used in offshore industry; however, presently their applications are prolonged to land and even subsea installations.
For over ten years, Abu Dhabi Company for Onshore Oil Operations (ADCO) has been using MPFM in several oil fields and concession areas. Being relatively the furthermost recent developed field, clustering options, and full application of i-field concept including collaborative environment (CWE); North East Bab (NEB) Asset is crowned for being the frontrunner in adopting the up-to-date technologies among other ADCO Assets.
NEB full field development was custom-built in 2005. Fifteen (15) number of conventional three phase test separators were put together for reservoir surveillance and production testing requirement and were lately refurbished and upgraded with Coriolis and V-cone meters rather than originally installed turbine meters. During this period, two portable MFPMs were contracted out in order to achieve the annual testing KPI and prospect was taken to validate the Coriolis and V-cone meters of the refurbished test separators using MPFMs'. This project facilitated instituting better communication protocols along with comprehensive collaborative workflow between NEB Asset and the service provider that resulted in successful completion of the revamping project. This as well had tremendously encouraged ADCO (NEB Asset) to permanently include MPFM flow metering applications in the upcoming future developments.
This paper aspires to share the valuable experience gained by utilizing the MPFM in NEB Asset for different flow metering applications, and to establish the technology adoption guidelines for other field operators.
Al-yateem, Karam Sami (Saudi Aramco) | Hanbzazah, Shadi Mohammed (Saudi Aramco) | Alsyed, Samih Masarrat (Saudi Aramco) | Fouad, Alaa (Schlumberger Middle East SA) | Al Mahamed, Saleh M. (Saudi Aramco)
In the oil and gas industry, safety systems are put in place to prevent the release of hydrocarbons and protect assets against any undesirable events. This can be accomplished by installing protective measures that monitor the process components, and can also control the process in case of undesirable events. The Surface Controlled Subsurface Safety Valve (SCSSSV) is one major component, which is mainly installed in wells that are located offshore or close to populations and environmentally sensitive areas. These SCSSSV can be categorized into two types depending on the deployment/retrieval methodology. The first type is referred to as the Wire Line Retrievable Subsurface Safety Valve (WLRSSSV), which is installed and retrieved by rigless well intervention and installed inside the production tubing. The other type is the Tubing Retrievable Subsurface Safety Valve (TRSSSV) and these valves are part of the tubing completion.
Due to its numerous advantages, like full bore access, and not to retrieve the valve before any intervention, TRSSSV are gaining more popularity. Saudi Aramco uses these types of valves and most of the new completions are designed with TRSSSV. Unfortunately, as these types of valves are part of the completion, any failure to close these valves results in a disturbance in the safety system of the well, which will lead to performing an expensive workover, which is not only costly but the process means killing the well, and therefore inducing damage to the reservoir. This paper presents in detail the procedure applied to these inoperable TRSSSVs to regain the safety of the wells and put them back on production without the need to de-complete the well. The direct business impacts are restoring the well safety system, wells' productivity in addition to cost avoidance of (onshore and offshore) workover operation to replace the malfunctioning TRSSSVs. The paper will also cover common mitigation measures to mitigate TRSSSV failure and avoid their conversion.
Real time digital slickline services have been used increasingly in the Gulf of Mexico by a number of customers. Through its telemetry enabled capabilities and the purpose built tools that complete the platform, digital slickline services can deliver a number of safety and efficiency gains to all types of slickline operations.
Material presented in this paper will be from actual operations, examples being perforation, tubing punching and cutting, plug setting and cement dump bailing, and will demonstrate the operational efficiencies being delivered.
Enhancement of the slickline service comes from real time surface readout of in situ tool operational status, the critical core measurements of downhole toolstring movement, deviation head tension and shock, and the depth precision now offered through gamma ray and CCL sensors. Optional tools such as a pressure / temperature gauge bring yet further visibility on the impact of the downhole actions undertaken. Expansion of the slickline service capabilities come from the telemetry enablement and core tools, coupled with a range of specific tools and sensors that have been developed to run on this slickline platform, namely a electro-hydraulic setting tool, an explosive triggering device, a monobore lock mandrel, and a production logging suite.
The real time data that is delivered to the slickline operator removes the need for assumptions that often have to be made during conventional slickline operation, and allow for a more efficient and reliable slickline operation to be undertaken. This results in a reduction in operation time, and a reduction in unnecessary trips out of the well to check on the tool status or to validate depth. Furthermore, since digital slickline is able to carry out both slickline well preparation work and a range of remedial or measurement work often carried out on memory or eLine, these operations can often be conducted entirely utilizing digital slickline crew and equipment. This optimizes pre- and post-job logistics, equipment rig up and rig down, and the job execution itself. In addition to the obvious cost savings, with a slickline wire comes a simplification of the pressure control and a well control recovery situation.
Eltayeb, May (Schlumberger) | Heydari, Mohammad Reza (Schlumberger) | Nasrumminallah, Muhammad (D&M-Schlumberger) | Bugni, Michael (Schlumberger, Oman) | Edwards, John Ernest (Schlumberger) | Frigui, Mejdi (Schlumberger Middle East SA) | Nadjeh, Imad (Schlumberger) | Al Habsy, Hilal (Schlumberger)