The Art of Geosteering in the Cleveland Sand: Discovering New Methods for Data Integration and Interpretation Using Gamma Ray and Scatter Graphs with examples from the Texas Panhandle.
With the ever increasing popularity of resource ‘plays’, it is important to maximize integration of all available types of data to assure profitable well completion. Geosteering in thin bed formations can be challenging because it is sometimes difficult to predict proper formation dip and thickness. To accomplish this, isopachs, and structural maps, as well as cross-sectional data must be used in conjunction with other nontraditional data collected while drilling. Today's geologist must scrutinize gamma ray and survey data to continually confirm or correct original stratigraphic and structural interpretations long after prospect generation. Measured depth and true vertical depth gamma ray logs data are one of the most important data sets that can be utilized from the time that directional tools are employed, throughout well completion. By examining the unique relationships between bit inclination, measured depth and true vertical gamma ray measurements, the steering geologist can make simple, yet powerful, observations about stratigraphic position in the target formation. One of the easiest ways to visualize these relationships is by using scatter plots and XYXY graphs. By overlaying several of these data sets as well as plotting several sections of the lateral in true vertical depth format, observations can then be made regarding localized formation dip and thickness. This method has proved useful in both toe-up and toe-down Cleveland wells drilled in the Texas Panhandle.
AAPG Datapages/Search and Discovery Article #90221 © 2015 Mid-Continent Section, Tulsa, Oklahoma, October 4-6, 2015