Integrating Horizontal Wellbores When Building a Geological Model of an Offshore Field

Abstract

With the advent of the equipment for full well logging suite in the horizontal wells, it became possible to evaluate the reservoir's quantitative parameters. However, the original curves are mainly used for this purpose, which leads to significant errors, in particular due to the significant influence of nearby reservoirs on the tools readings in the penetrated deposits. There is a need to discuss the current issues of interpretation in directional, horizontal and multi-lateral wells with the experts. 3DP module in the downhole software platform* allows to evaluate the overall influence of geometric effects, as well as to adjust logging curves for the influence of several reservoirs on the logging tools responses, which are not still taken into account by conventional methods when processing. The modeled density image is especially useful for confirming the model geometry, updating the local dip angle, and identifying areas, where additional features, such as thin layers, are to be added. The accounting for density and neutron porosity for layers in the petrophysical analysis increases the efficiency of calculating clay volume and porosity, which affects the saturation. The authors also proposed a methodology for assessing share of sand component based on RHOB image. Further accounting of NTG, for the correct assessment of the reservoir properties in a heterogeneous reservoir, followed by the data accounting in the geological model. The results obtained in the course of the work allowed to apply the spatial interpretation of horizontal well in geological modeling, as well as to improve the interpretation algorithm.