Methods for determining reasonable well spacing in evaluation on offshore gasfield development
In the evaluation on offshore gasfields,conventional approaches to determine well spacing are limited by the number of appraisal wells and the availability of geological data.Three universal ones among them were selected as research objectives,includ-ing reasonable well-control reserve method,reasonable well productivity method,and reasonable gas recovery rate method.Their key parameters were defined,namely the stable production,reasonable gas recovery rate,years of stable production,and unproductive ef-ficiency at the end of stable production period.Moreover,chart regression dependent on analog data was used to figure out value-tak-ing schemes for each key parameters.And through statistical regression and probability analysis,some empirical charts were built for different types of gas reservoirs with various physical properties.Results show that(i)both table and form of statistical regression can be used to quickly determine the above-mentioned key parameters;(ii)the well-control area and unit-thickness well-control reserve methods formed can be used for direct reading and rapid determining well space,and(iii)after the application to a deep-water A gas-field with low permeability in West Africa,the reasonable spacing ranging from 1,000 m to 1,200 m is fixed.These results may offer experiences on the reasonable determination during field development.
Offshore gasfieldGasfield evaluationReasonable well spacingRecovery efficiencyWell-control area methodUnit-thickness well-control reserve method
万方数据
维普
