An important objective of a surveillance programme for a gas condensate reservoir is to accurately assess reservoir pressure depletion over time. However, partial-to-complete isolation of zones throughout such a reservoir complicates the collection and interpretation of reservoir pressures from pressure transient analyses alone. As a result, production logs are run to obtain zonal flow contributions to understand the status of zonal pressure depletion. Understanding these zonal contributions and their implications on zonal pressures requires an integrated knowledge of the geologic and operational controls on flow.Integrated Geologic and Engineering Modeling Studies (iGEMS) is a workflow designed to provide this integration and, thereby, increase the value of surveillance data. iGEMS focuses on identifying well-level geologic and operation controls on flow. iGEMS uses an efficient process to rapidly create, run, and analyze single-well simulations that include the effects of boundary pressures and compositions inherent in the parent model.A case study utilising the iGEMS workflow is covered in this paper. This case study provides a specific example of how iGEMS teams identify geologic and operational controls on reservoir performance and develop a better understanding of zonal pressure differences. iGEMS provides insights on these controls by using reservoir modeling as a tool to integrate surveillance data, well logs, core data and geologic observations. Understanding what is controlling flow in the reservoir helps engineers, geoscientists, and petrophysicists make better operating decisions to maximise reservoir performance.

Monitoring individual layer performance (in commingled completions) and integrating the results into an overall understanding of field performance has always been a challenge. Overcoming this challenge allows for a better, layer-by-layer, understanding of the reservoir, and therefore will have a significant impact on well and reservoir management. This paper presents a success case for the integration of a novel approach, and specific applications are highlighted. The Khuff Formation of the North Field is a multi-layered carbonate reservoir formed from four main reservoirs; K1, K2, K3 and K4. As most of the RasGas wells are completed commingled through the main Khuff reservoirs, a hybrid approach for integrating multi-layer pressure transient analysis (PTA) with production logging tools (PLT) analysis of flow and pressure profiles was developed. The process also accounts for the physics of carbonate matrix acidisation. The outcome of this technique has helped RasGas better assess the stimulation effectiveness in commingled wells, and establish baseline performance for individual layers. This work was used to build improved inputs for reservoir simulation models, thus providing more accurate predictions of reservoir performance. Additional benefits of this technique have been: 1) identification of wells with impaired productivity (candidates wells for re-stimulation), 2) a better understanding of the stim jobs (areas for improvement for future jobs), and 3) an improved understanding of log kh vs test kh variation (to understand specific questions on well performance). This paper discusses the outcomes, applications, and the added value of this integrated methodology. The paper will also demonstrate examples where the technology was applied and the value that was added to the ongoing surveillance and future development activities.

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The use of a terrestrial laser scanner to capture outcrop information has grown in popularity in recent years as a complementary method to geological field work. Laser scanning technology provides a huge volume of geo-referenced data which can be integrated with other datasets. It not only allows 3-D visualisation of the scanned outcrops but also complex qualitative and quantitative analysis of outcrop information.Light Detection and Ranging (LiDAR) technology was used as the basis for development of an interactive 3-D stereoscopic module of ancient outcrop analogs for Khuff Formation deposited in Eastern Arabian Peninsula. Seven of these outcrops, located in Wadi Bih and Wadi Hagil (Ras Al-Khaimah, U.A.E.) and representing carbonates of the Permo-Triassic Bih, and the Triassic Hagil and Ghail formations were captured using LiDAR technology.In order to obtain the highest quality dataset for visualisation purposes, a terrestrial laser scanner with mounted calibrated digital camera was used to capture outcrop information. The outcrops show lateral and vertical facies variations and stacking patterns comparable to Khuff Formation carbonates of the subsurface of the Middle East. Thicker-bedded, shallow subtidal, high-energy grain-dominated carbonates developing around high-frequency maximum flooding surfaces and thinner-bedded peritidal, low-energy mud-dominated and often microbial-laminated carbonates underlying parasequence boundaries and high-frequency sequence boundaries are features that can be well observed in this dataset. Structural features such as fracture networks, collapse features, vertical low-offset faults and mechanical stratigraphy observed at the outcrops are also captured and documented to help understand fluid flow behavior.All supporting geological interpretation and information are linked interactively to the LiDAR dataset using point-andclick menus to enhance its effectiveness. The 3-D virtual product captures the valuable knowledge of LiDAR scanned outcrops in a fashion that can be used for self-study, training, and pre-field trip and workshop discussions. IntroductionKnowledge and technology are key resources and long recognised as being of central importance to any organization and contributing to business success. In oil and gas sectors, knowledge and technology have helped companies to sustain their positions and adapt themselves to the challenging operating environments and declining resources. Ability of these companies to reduce operating costs and maximizing recovery is significantly impacted by the quality of knowledge and technology employed into the development plan, especially in the assessment of subsurface environments.Subsurface geological data plays a significant role in providing the oil and gas scientists and engineers the ability to understand subsurface reservoir heterogeneities that impact fluid flow. This data comes in many sizes, from kilometer-scale regional seismic lines to millimeter-scale drill cuttings. Interpretation models derived from the data will be used subseq...