Abstract
The aim of this paper is to outline a fast and reliable workflow that allows delivering a rapid and high-level evaluation of reservoir performance based on surveillance data. Exploration prospects, single well analysis and quality control of full field models are typical opportunities for the application of fast track evaluations. The integration of data in simplified workflows is a sufficiently robust approach to provide reasonable analyses, mainly where time and resources are limited.
To illustrate the fast track process, petrophysical and well test evaluations are combined to generate sufficient information to enable the prediction of reservoir performance using a very simplistic and optimized workflow. Wireline data and information from permanent downhole pressure and temperature gauges are used to assess well performance and to forecast potential reservoir offtake. To test the effectiveness of the workflow, a case study from a field in Europe has been carried out.
Well production testing is extensively used during the appraisal stage, to build confidence that hydrocarbons can be commercially produced, and during field development, to monitor well productivity performance through time. Using well test analysis (WTA) reservoir characterization, reservoir container volume, depletion mechanisms, reservoir connectivity and distance of wells to boundaries can be addressed, using as input, petrophysical, geological data and fluid properties. Petrophysical data is fundamental to the evaluation of well potential and the identification of possible productivity issues related to well integrity and/or formation damage. A pressure derivative plot against time, with both axes on a logarithmic scale, shows a specific fingerprint associated to geological features such as layering, permeability, faults, fractures and channels.
This paper will be of interest to engineers, geoscientists and asset managers who need a quick evaluation workflow that integrates well and reservoir data to deliver consistent and robust assessments. The ability to complete reliable fast track well test analysis has a direct impact on reduction of cost and deferred production for operators and joint venture partners.
