Application of conventional decline curve analysis following Arps' method is limited to situations where flowing bottom-hole pressure is constant. This paper describes the application of Blasingame decline curve analysis in a low permeability reservoir where flowing bottom-hole pressures are reduced in frequent and managed steps.The Valdemar Lower Cretaceous Field is a low effective permeability (from 0.1 to 1 mD) chalk reservoir developed offshore in the Danish North Sea through long horizontal wells (horizontal sections of approximately 10,000 ft) with up to 16 sand-propped fractures.Pressure drawdown in Valdemar wells is managed by controlled lowering of the flowing bottom-hole pressure over time in order to avoid destabilization of the formation and well failure due to chalk production. These changes in operating conditions, in addition to reservoir complexity and challenging architecture of the wells make conventional methods (simulation, Arps' decline curve analysis and rate transient analysis) for production forecasting and well performance analysis either not adequate or difficult to implement. These issues have been resolved by applying advanced decline curve analysis to the variable rate / variable pressure drop theory.Application of the Blasingame Theory for the Valdemar Lower Cretaceous Field using available commercial software is complicated as it requires input parameters which are not very well known such as fracture half-length, fracture conductivity and number of producing fractures. In addition, uncertainty in fluid and reservoir properties can make the task even more challenging, since a non-unique history match often results with subsequent predictions outside a reasonable range. This paper presents a clear step by step, performance-based methodology of how to apply the Blasingame Theory to decline curve analysis. The methodology does not depend on detailed knowledge of well and fracture dimensions and it only requires the initial reservoir pressure, historical oil rates and flowing bottom-hole pressures to be known for production forecasting. This paper also presents the practical application to the Valdemar Lower Cretaceous Field. This methodology has been demonstrated to work in the Valdemar Lower Cretaceous Field and it is currently the key tool used to evaluate well performance and to estimate reserves and resources associated with different production strategies (drawdown, gas lift, etc.).

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TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractThe paper discusses the discovery, development, and operation of a miscible gas cycling project in a highly undersaturated, volatile oil TAGI reservoir in center of the Berkine Basin, Algeria. Miscible gas injection was initially considered to be high risk and marginally economic; however, with a flexible development plan and careful reservoir management carried out by an integrated team of surface and subsurface disciplines, a successful project was implemented.In RKF field, a significant portion of the oil-in-place is in the oil-water transition zone, permeability is low, clay content is high, the oil contains asphaltenes, the formation water is salt-saturated, and the fluvial stratigraphy is complex. Design of a successful gas injection project was particularly challenging under these conditions. The RKF project demonstrates the importance of acquiring dynamic data early in the appraisal phase tracers and extensive data acquisition was critical to project optimisation and for solving operational `problems such as salt and asphaltene precipitation, minimisation of downtime, maximising liquid recoveries, and balancing of reservoir pressure throughout the field. Integrating all surface and subsurface engineering data, on a continuous basis, with the evolving geological and geophysical interpretations was critical to project success.

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Pe d a g o g i a i Tr e b a l l S o c i a l . R e v i s t a d e c i è n c i e s s o c i a l s a p l i c a d e s . 2 0 2 2 . Vo l . 1 1 Nú m . 2 • I S S N : 2 0 1 3 -9 0 6 3 [ Pà g. 5 7 ] mienta está basado en el enfoque de comprensión del sinhogarismo de la nueva ortodoxia, permitiendo asociar los cambios en el estatus residencial a variaciones en la vinculación a estructuras de apoyo formal, de apoyo informal y de desarrollo de capacidades. El enfoque permite mejorar la comprensión de los cambios en el estatus residencial y profundizar en el efecto de los programas de intervención sobre la población atendida. La herramienta ha sido testeada en dos programas de intervención con personas sin hogar en la ciudad de Valencia y ha resultado un mecanismo efectivo permitiendo mejorar la implantación de estructuras de monitoreo y evaluación en el abordaje del sinhogarismo.