Borehole images logs are commonly run in the oil and gas, CCS and geotechnical industries, but are often not used to their full potential for characterisation of subsurface formations. Borehole images are perfect for this purpose as they bridge the scale gap between core and seismic data and are the closest thing to being able to carry out field geology in the subsurface since they provide dip orientation data as well as compositional, textural and even in some cases grain size information that can be applied to tasks such as sedimentological facies classification, sedimentary body dimensioning and geometry determination, interpretation of depositional environment and even sediment dispersal trend analysis. In turn, with integration of supporting data from other sources such as core or well testing and correlation to seismic data, the image logs can be used to populate geological/reservoir models with reservoir properties and vastly reduce the uncertainty in such models.
A vast array of different image measurement techniques can now be used to acquire borehole images either whilst drilling or during subsequent logging operations. The choice of imaging devices can be very confusing, and it is often forgotten that different image types have different sample resolutions that will affect their utility, but there are appropriate tools to characterise all sedimentological environments even in very complex situations such as sand injection systems.
Task Fronterra Geoscience are a specialist borehole image interpretation group and in this workshop we will aim to provide an overview of the rich variety of information that can be gleaned from these logs with application to all depositional environments, even complex environments such as sand injection systems. In addition, we will look at how image logs can help populate geological/reservoir models with a better understanding of properties such as facies, sedimentary body dimensioning and geometry determination, interpretation of depositional environment and sediment dispersal trends.