Understanding of fluid movement in and near the wellbore is a crucial factor for effective reservoir management including successful remedial actions and field development planning. One of the key objectives in well surveys is to detect and locate sources of fluid flows behind multiple pipe barriers. The conventional Production Logging Tool (PLT) is run to detect fluid flow and identify the type of fluid under downhole conditions, but is limited to measurements only inside the wellbore. Similarly, other diagnostic techniques, such as cement bond logging, give insight only into the cement integrity and also have limited capabilities to detect cross flows behind casing.Recent developments in temperature and noise logging tools and advanced interpretation techniques have provided higher resolution and sensitivity, enabling the detection of previously undetectable leaks and fluid flow behind casing [1].In the present case, a water zone has been identified in a producing formation with High Precision Temperature (HPT) logging and Spectral Noise Logging (SNL) followed by advanced numerical temperature modelling using the TermoSim software application. SNL identifies flowing zones and differentiates between rock-matrix and fracture flows, and TermoSim then numerically models heat exchange between the wellbore fluid and the surrounding rocks and reservoirs. The resulting model quantifies fluid production from each reservoir unit. Conventional production logging (PLT) locates fluid entry points in the wellbore. The integrated HPT-SNL and PLT logging suite can trace the entire water path from the reservoir into the wellbore. This paper describes water source identification by an HPT-SNL-PLT logging suite deployed in several production wells of a Kuwait oil field. In some of the wells in this field, it has been found that water encroached into the perforations from a watered reservoir below through a channel behind the casing. In other wells, it has been found that cold water breakthrough occurred laterally from nearby water injectors. The exact identification of water sources is a crucial step in any further well remedial work to reduce or eliminate them from oil producing wells. [2]

Raudhatain-Mauddud, a super-giant depletion-drive oil reservoir in North-Kuwait, is undergoing massive development efforts, with a planned enhancement in oil production through phased pattern-waterflood. The Phase1-development covers the crestal-area of the structure, which is the focus for current development efforts through 8 inverted 9-spot patterns. This poster outlines the successful integration of a lot of team's collaboration to significantly improve the operating procedure for water flooding. This effort required a new way of managing this reservoir: a comprehensive approach of balancing voidage with injection, conducting extensive surveillance/analysis to assess the efficacy of various courses of action and, most significantly, adjusting various teams' "key performance indicators" to align injection and production allowable with sound reservoir management principles. An innovative unified information management system was used to monitor voidage replacement ratio (VRR) to provide a basis for pattern balancing. A very extensive surveillance operation provides the data necessary to monitor individual pattern balance and water cut performance, optimizes areal sweep efficiency by adjusting injection and production allowable, assist in planning water-shutoff operations, and design new completions. Time lapsed monitoring and the surveillance data indicates the reservoir is relatively well connected. However, after applying the new management approach, individual waterflood pattern balance is significantly improved and the field-wide VRR is around 1.2. All of these activities have led to the enhanced understanding of the waterflood behavior and the model updates. Sound reservoir surveillance and waterflood management procedures implemented within a diverse group of teams that have performance goals aligned with "best practice" has resulted in effectively re-balancing this major waterflood.

Raudhatain Mauddud is an oil bearing carbonate reservoir in North Kuwait. Mauddud consists of 10 layers with different fluid properties (API from 30 to 14 Deg). Oil production started in year 1957 till year 2000 when started full filed waterflood project. There was quick and clear positive response to water injection in both reservoir pressure and oil production. However there was early water breakthrough in some wells. Many factors have increased challenges in managing Mauddud waterflood project. These challenges were mainly due to reservoir heterogeneity in all layers, structure, injection of low saline water, difficulty to evaluate remaining potential in flooded wells or to identify thief zone before start the injection. Consequently, the water management strategy has been adapted by implementing methods and tools to tackle these challenges. Interwell tracers have been implemented to study and monitor water movement from the injectors to the producers and evaluate the sealing nature of the faults. Pattern x-section including Tracer, PLT and production data has been used under one page to assist in evaluating and studying water movement within the reservoir. Automated Workflow has been established to calculate VRR for each pattern. Surveillance plan has been implemented including inference tests and PBU/PFO. The injection to production connections and profiles has been modified by isolating top intervals in the injectors and drill horizontal injectors in the bottom of the reservoir. The new horizontal producer has been drilled in the top of the reservoir with advanced completion technology of ICD. Managing Mauddud Waterflood project in that way has resulted in increase of total Mauddud daily oil rate by 20% with drop in water cut from 40 to 33%. This paper is summarizing the methods that have been used to manage Raudhatain Mauddud waterflood project as best practices.

RAMA-Pilot1 is a Mauddud open-hole well which is located in Raudhatain field-North Kuwait. The well had a barefoot completion and it was producing on ESP. Due to low rock quality, the well was performing less than expected levels.It was selected as an acid tunneling pilot for this project to create tunnels and new pathways inside the open-hole section. This is to increase reservoir contact, improve well productivity & eventually increase the near wellbore deliverability.Two tunnels were created successfully inside the open-hole section and the results indicated that the productivity index increased by 3 times from 1.3 to 3.87 bpd/Psi. This successful job was also possible from the lessons learnt, from an earlier attempt of acid tunneling in an Effluent Water Disposal (EWD) well. The job was not successful, and subsequent failure analysis of the job showed an "undersize tool in an oversize hole". So this time sufficient care was taken to measure the hole size properly to size off the acid tunnel tool accordingly.RAMA-Pilot1 success had not only lead to restore & increase well production, but it would also pave the way to enhance oil production and opening up possibilities for field wide applications especially in low PI carbonate reservoir wells. Also, it is considered for improving EWD wells performance by this technique.RAMA-Pilot1 is the first "dendritic" well with extensive worm holes created by acid tunneling for maximum reservoir contact. The whole effect is aptly demonstrated by the change in PI of the well before and after the acid tunneling as mentioned before.This technique can be planned for any type of wells (EWD, oil well, water injector) provided there is an open hole and tunnel that is created will be stable.Econimically, acid tunneling technique compares favorably with alternative stimulation options in both time and money savings.

Monitoring the reservoir pressures throughout the production life of the field is considered as a cornerstone for reservoir management and optimization of the development plans. There are many challenges to have routine and proper pressure records. Multi-zone single completion wells are one of these challenges, where it is difficult to acquire the reservoir pressure for each zone through the conventional pressure gauges. In addition to that, deferring the production or injection of high rate wells for quite time to acquire downhole static pressure data is adding more to these challenges. Raudhatain Zubair Reservoir is a layered reservoir with difference in reservoir pressure from layer to the other. Spectral Noise Logging technique has been utilized to estimate the average reservoir pressure for each perforated layer in a Multi-zone single completion oil producer. The noise logging survey has been carried out under flowing conditions and on different rates. The process of estimation the average reservoir pressure from Noise logging is based on quantification of the noise power under different rates. The signal recorded by SNL has two main parameters: amplitude and frequency. The frequency ranges widely from 8 Hz to 60 kHz, while the amplitude increases with differential pressure. The power of the acoustic noise signal generated by a reservoir fluid flowing from a particular unit is directly proportional to the product of differential pressure and flow rate. Nonlinear relationship between the noise power and bottom-hole flowing pressure has been utilized to estimate the average reservoir pressure which stays valid under monophasic flow conditions for the hydrocarbon to the wellbore. The estimated pressures for each layer from this technique matched the RFT pressure data that have been recorded in the nearby wells and in also RFT data recorded in same well considering the production history. The noise profile has also indicated the effective sand thickness for each layer and investigated flow behind the casing from non-perforated reservoir to the existing perforations. Utilization of the SNL logging to estimate the reservoir pressure is adding more to reservoir surveillance applicable tools that could mitigate some of the existing challenges and aiming to improve the surveillance process under certain circumstances. This paper presents a case of applying the noise logging in an oil producer with the detailed job procedures, measured data, interpretation process, and the final results