The Concept of Sedimentary Steering: A New Sedimentological Dimension Using High Resolution Electrical Borehole Images While-Drilling

Jeremy Lofts and Stephen Morris
INTEQ, Houston, TX

A broad range of sedimentary features can now be observed from high definition borehole images acquired while-drilling. Work to date shows that textural analysis, facies discrimination and feature orientation for sedimentological application can be interpreted from these data (like traditional image/core interpretation).

This in-depth study, detailing core log and borehole image analysis and calibration discusses the concept of Sedimentary Steering. This entails the use detailed of high-resolution sedimentological features for advanced Reservoir Navigation (geosteering) aimed at reducing uncertainties related and improving steering within the desired “sweet-spot” of a variety of clastic and carbonate reservoirs. It is focused around both a vertical and horizontal components; (1) the positioning and steering within a particular unit in the vertical positioning sense and (2) the position relative to the lateral margin of the reservoir body (sandbody geometry). The development of sedimentary steering will use real-time feature-picking to further enhance knowledge of the sandbody and will forward-model the likelihood of bounding surfaces and cross-lamination.

The results of this study will also highlight several geological/sedimentological criteria that will be useful in the successful deployment of sedimentary steering.

AAPG Search and Discover Article #90078©2008 AAPG Annual Convention, San Antonio, Texas