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Mud Pulse Telemetry (MPT) is the most common down hole-to-surface communication technology utilized by MWD/LWD systems. Compared to alternative technologies, MPT systems are characterized by a proven record of high reliability in a wide range of operating environments. Reliable data delivery is feasible in a variety of scenarios ranging from shallow vertical to complex, deep water wells in all types of drilling fluid media.Recent years have seen the introduction of many new LWD technologies which are providing unparalleled amounts of wireline quality evaluation data in realtime. Access to high quality, complete, evaluation data sets whilst drilling is enabling geologists and engineers to make decisions with higher confidence based on more and higher quality datasets, consequently enabling wells to become more complex and fulfill multiple objectives. The ever increasing volume of information generated by these new technologies has begun to exceed the bandwidth transmission capacity that traditional MPT technology can deliver. To fully capitalize on the LWD technological advances being implemented, an increase in data transmission speeds is required. This paper discusses a new telemetry system that delivers data rates in excess of 6 bits per second (bps). The system has been deployed in a number of complex 3D extended reach offshore wells in Norway. During operations, the system reliably delivered high data rates of up to 20 bps, resulting in improved drilling efficiency, and reduced operational risk due to enhanced realtime decision quality based on the improved quality of FE and downhole diagnostics data.

Over the past decade several attempts and methods have been applied to ensure remote operations—from moving operations directly from offshore to onshore to a complete redefinition of work processes and responsibilities. This paper demonstrates how a different work methodology onshore improves the reliability in the total drilling and logging while drilling (LWD) operation, focusing on combining drilling and evaluation work processes and technologies. This paper presents several cases where combining drilling optimization with LWD formation evaluation greatly enhances the understanding of the subsurface environment. The main goal is to optimize the drilling progress with regards to hole condition and reliability combined with optimum well placement. The elements involved in this process include:Use of downhole drilling dynamics measurements and interpretation of these to determine required action to reduce any damage to the downhole sensors and to ensure the energy is used to penetrate new formation.Use of LWD data both for understanding the overall drilling regime and for optimum well placement. In combination with LWD formation evaluation, any changes in the rock penetrated are instantly taken into the drilling optimization procedure, and parameters are then optimized to maintain maximum progress. In this way, the guesswork about changes in the rock properties is eliminated, and the correct action is implemented instantly. In addition to the downhole technology, the work flow procedures and distribution of responsibilities throughout the team will be explained. Strong collaboration between the different team members is essential to make this process work. Introduction To make drilling progress while at the same time achieving optimum wellbore placement, a multidisciplinary approach is necessary. Over the last several decades this approach has proven difficult, and several different approaches have been performed over the last few years. In many of these efforts, the organizational structure has been a hurdle. The strong professional belonging in either drilling or geoscience or even within the different departments or professions within the broader disciplines, often presents a boundary that requires consideration to facilitate collaboration. To create a strong multi- and cross-divisional team, the organizational structure was changed to obtain the best possible delivery of the well. By creating a multidisciplinary team with focus on both the data acquisition as well as the real-time usage of the data, a more widespread understanding of the well objectives and common foundation is created. In most circumstances, the geoscience personnel are focusing on the reservoir part whilst drilling personnel are equally occupied with the drilling of the overburden and encountered drilling-related obstacles. To gain a full understanding of the rock and drilling progress, information normally obtained to enhance reservoir understanding is used. In general, acoustic and density data are acquired to obtain information around time depth conversion of the seismic, but are equally valuable in the drilling process.

This paper describes geological and petrophysical evaluation of a new structure of a mature field to evaluate the reservoir potential in unproduced reservoir zones. The well was drilled in a carbonate with variations in rock quality and with minor subfaulting occurring. Gamma ray (GR), resistivity, density, neutron, and image services were used in the horizontal part of the well in addition to magnetic resonance (MR). To achieve the best possible real-time wellbore placement, reservoir navigation and continuous follow-up on the horizontal log interpretation were performed during drilling.For the first time, a low-gradient-MR-while-drilling technology was deployed in a virgin carbonate horizontal well on the Norwegian Continental Shelf. The MR service was run to obtain porosities (including partitioning of movable and bound fluids), hydrocarbon (HC) saturations, and permeability estimates. Fluid saturations based on traditional methods and the MR were evaluated and compared by core data, enhancing the understanding of the measurement and the reservoir. For post-processing, the MR data were integrated and interpreted together with the other measurements performed in the well, delivering an accurate and consistent reservoir description.The first part of the horizontal part of the well was drilled with conductive drilling fluid and the latter part with nonconductive drilling fluid. Laboratory measurements for the two mud filtrates were performed to understand the influence of the two different drilling-fluid types on the MR measurements. In the absence of water-based mudfiltrate invasion, the MR data show good agreement with saturations from core, confirming the quality and reliability of the MR data.Comparison of the MR T 2 distributions and volumetrics with image data indicates that even fine variations in rock quality and lithology are reliably resolved by the MR data. Before logging, old core data were used to refine the constants used in the Timur-Coates MR permeability equation, which quantitatively tracks changes in reservoir quality. The values were calibrated when Timur-Coates constants were derived from the well's core plugs.

The Grane field causes significant challenges with respect to reservoir drainage and wellbore placement. The true resistivity profiles from offset wells are reflecting an irregular oil water transition zone in the field, likely to be caused by subtle facies variations and/or local variations in the oil water contact (OWC). In addition, horizontal wells penetrated many shales.Baker Hughes INTEQ has in collaboration with Hydro developed an extra deep resistivity service called DeepTrak™ to navigate at a distance of up to 12 meters from a resistivity contrast boundary. This service has been used in several wells.The tools as well as the surface software components provided full service capability and were used successfully to geosteer along the OWC at the required distance. In addition, the DeepTrak service was capable of detecting shale injectites, thus giving valuable insight for reservoir characterization and geological model update.By use of field data, it is demonstrated how the DeepTrak service can be used for accurate wellbore placement.