No abstract

No abstract

Геолого-физические исследования и комплексное изучение пласта, как важнейшие инструменты для предсказания поведения трещиноватых и карстифицированных пород Харьягинского месторождения Наталья Щукина, Тоталь РРР; Катерин Ньюманн, Тоталь С.А.; Жорж Нели, Тоталь С.А.; Винчензо Спина, Тоталь С.А.; Жан-Люк Дебру, Тоталь С.А.Авторское право 2013 г., Общество инженеров нефтегазовой промышленности Этот доклад был подготовлен для презентации на Конференции SPE по разработке месторождений в осложненных условиях и Арктике 15-17 октября 2013 года в Москве, Россия.Данный доклад был выбран для проведения презентации Программным комитетом SPE по результатам экспертизы информации, содержащейся в представленном авторами реферате. Экспертиза содержания доклада Обществом инженеров нефтегазовой промышленности не выполнялась, и внесение исправлений и изменений является обязанностью авторов. в том виде, в котором он представлен, не обязательно отражает точку зрения SPE, его должностных лиц или участников. Электронное копирование, распространение или хранение любой части данного доклада без предварительного письменного согласия SPE запрещается. Разрешение на воспроизведение в печатном виде распространяется только на реферат объемом не более 300 слов; при этом копировать иллюстрации не разрешается. Реферат должен содержать явно выраженную ссылку на авторское право SPE.

This paper presents an integrated Geosciences and Reservoir work approach used for complex fractured and karstified carbonate Kharyaga field. Synthesis is fulfilled for all available data, such as seismic interpretation, static well data, well tests etc. It has been launched on Kharyaga field mid 2012. Kharyaga field is a NW-SE elongated anticline lying 60km north of the Artic polar Circle, in Nenets Autonomous Territory on Kolva regional swell. Total E&P Russie (TEPR) is operating Object 2 and 3 of this field. The Object 2 accumulation, subject of this study, is characterised by oil bearing Devonian carbonate reservoir with a gross thickness of 160–250m with high vertical and lateral heteregenity. Current production from Object 2 is around 23 kbopd. The purpose of the synthesis is to create new and more reliable geological and dynamic models in order to better optimize next development phase and fine tune production profiles estimation. Geosciences and Reservoir synthesis imply the following: gathering all available information starting from newly reprocessed seismic data, various static well data and ending by well tests and production history over the whole life of the field,depth analysis and putting in coherence of all information in order to better address the various heterogeneity scales and reservoir characterization. There are two main challenges related to characterization of existing heterogeneities: defining the fault pattern including sub seismic faults, understanding karst and fractures distribution,defining vertical and lateral sedimentary heterogeneity as well as reservoir extension. Many experts and specialists are involved in this synthesis. The joint approach between geologist and geophysicist, based on tectno-stratigraphic timing and stress field combined with seismic attributes and thickness map, allowed to proposed a new fault pattern which honors FMI data and dynamic interference tests recorded during the 14 years of field production. Interpretation of newly reprocessed seismic data helped the sedimentologists in inter-well correlation. Looking just at seismic amplitudes cubes, it was possible to propose a new sedimentary model and change inter-well correlation accordingly. This led to the updated vision of the reservoir.

Kharyaga Upper Devonian oil reservoir, developed through water injection, is part of a highly heterogeneous carbonate platform. Three sedimentary domains can be identified from South to North: a microbial reef-flat, back-barrier grainy shoals and a non-reservoir lagoon. Static and dynamic data gathered since production start-up revealed that the barrier is extensively fractured and karstified and shows a dual permeability behavior. Understanding the distribution of the dual medium is key to successful development of such a complex reservoir.To capture the relative weight on the flow network of each type of heterogeneity, a new workflow to characterize the dual medium has been developed, including the following steps: karst facies identification from cores and borehole images, comparison of the karst facies over a detailed flow analysis including detailed PLT interpretation; analysis of the facies spatial distribution using various diagenetic scenarios. As a result a new integrated vision of the reservoir and flow system has been consolidated and 3 main emersions followed by a hydrothermal phase have been identified. Each individual emersion generated a complex karst system composed of several components linked to the paleo-topography.Representing properly such a heterogeneous system was coped with by iterating in order to match the dynamic data. A two-stage modeling workflow was used: (1) fast iteration process using a dedicated stochastic tool which generates karst conduits, constrained by infiltration zone, paleo-water-table and paleo-topography; (2) once the right inputs are captured, the forward modeling workflow simulated the process of dissolution and generated at very fine scale a more complex and more consistent system.Finally, this work allowed to model different representations of this complex reservoir capturing the range of remaining subsurface uncertainties and consistent with the integrated interpretation of static and dynamic data. It allows to highlight and evaluate quantitatively the stakes of current and potential new development.