Presenter
Simone Huwe & Roger Burgess from Equinor
Co-authors
nan
Abstract
Biostratigraphy is the study of the distribution of fossils within sedimentary strata and has a broad range of applications including stratigraphic age constraint, wellbore correlation, and paleoenvironmental interpretation. Over the last few decades biostratigraphy has proven to be an invaluable tool within geosteering activities, and by integrating biostratigraphic data with real-time drilling information, geologists can make informed decisions on wellbore placement, optimizing hydrocarbon recovery, thus reducing drilling risks. This is particularly critical in complex geological reservoirs, where traditional geophysical and petrophysical methods such as seismic imaging and log correlation may be ambiguous or insufficient.
The application of biostratigraphy whilst geosteering relies on the extraction and identification of fossil assemblages from ditch cutting samples, particularly microfossils such as foraminifera, nannofossils, and palynomorphs. These serve as biostratigraphic markers that enable geologists to precisely correlate subsurface rock units and predict lithology distribution ahead of the drill bit in real time, allowing for adjustments in wellbore trajectory accordingly. This enhances drilling precision and optimizes wellbore placement leading to significant economic benefits. It also reduces the need for costly sidetracks and minimizes non-productive drilling time. Additionally, the ability to stay within the most productive zones of a reservoir maximizes hydrocarbon recovery, thereby improving the overall efficiency of the extraction process.
The synergy between biostratigraphy and geosteering represents a significant advancement for optimal well placement. It offers a robust framework for real-time geological interpretation and decision-making, enhancing the ability to navigate complex subsurface environments with greater confidence and accuracy. As a result, the integration of biostratigraphy into geosteering workflows is a standard practice in the industry, reflecting its importance in modern hydrocarbon exploration and production strategies. Equinor has recognised this importance and routinely includes biostratigraphy as part of the geosteering toolbox.
Biography
Simone Huwe and Roger Burgess are both Biostratigraphers working within Equinor