Application of Condensate Content Prediction for Shale Reservoir in Different Development Stage

This paper presents a technology for predicting condensate content for shale reservoir in different development stage. In early development stage, two important rules were found: the first one is there is a good positive correlation between hydrogen index (HI) and condensate content; the second is there is also a good positive correlation between ethane C13 isotope, propane C13 isotope, butane isomer ratio iC4/nC4 and HI. By means of these two rules, the limited core and cuttings analysis data can be used to solve the problem of insufficient data and predict the condensate content in the early development stage. In scale development stage, a large number of data from horizontal wells with staged fracturing are used to analyze condensate content, the dynamic production data can be used directly for predicting condensate content, much more geochemical analysis data from core and cuttings on horizontal sections of horizontal wells are also used to improve the prediction accuracy of condensate content. The average condensate content of the shale reservoir in Duvernay in Canada is 625 g/m3, and is complexly distributed in plane. Based on core, cuttings and production performance, the technology for predicting condensate content of shale reservoir in different development stage was adopted, the condensate content in plane was predicted accurately, zones with different condensate content were divided. Combined with production practice, the zone with very rich gas condensate and part zone with rich gas condensate were choosed as favorable zone for horizontal well arrangement.