A New Techniquein Aquiring High Quality Image Logs in Deviated & Horizontal Wells, Case History

Abstract

TX 75083-3836, U.S.A., fax 01-972-952-9435. AbstractWell bore images become increasingly important in identifying formation features and their possible extent. There are two different tools that acquire image data, acoustic and micro-resistivity. Both tools faced difficulties and challenges in acquiring quality data over the deviated and horizontal section of a well.To perform quality image data in deviated and horizontal section of a well is difficult because of; firstly, drilling rogues, deviated and horizontal section, and these results in poor padwall contacts. Therefore, the quality of the resistivity image data is highly affected by the drilling fluid, along with the acoustic data. Secondly, poor mud properties that behaves as a blocking medium to acquire quality data.A new technique requires modifying in both drilling and mud properties has been applied in different fields with high success. This new technique requires certain bottom hole assembly and drilling parameters, along with drilling fluid properties to better drill smooth holes.The new technique resulted in smooth horizontal section and better in the deviated section, therefore, better pad-wall contact. Images from both; resitivity and acoustic modes provided high quality data acquisition. As a result, geological features were very clear by the image logs after the implementation of this new technique.In this paper, the new technique is explained along with case histories from three different fields of the image logs are presented and compared to previous poor quality logs.