Remote monitoring of well site biostratigraphy

Abstract

Real-time well site biostratigraphy monitors the stratigraphic progress of drilling wells and can show if the well is conforming or deviating from predicted stratigraphy; it can also show whether total depth criteria have been met. New technology implemented by BHP Billiton Petroleum on wells in the Gulf of Mexico make it possible to undertake well site biostratigraphy remotely. An automated microscope has been developed that can scan and photograph nannofossil slides at a quality almost indistinguishable from conventional microscopy. A technician present at the well makes a slide from ditch cuttings and places it on the microscope, where software scans the slide at several focus levels, compresses the files and transfers the images to the office. A biostratigrapher in the office looks at the images and makes taxonomic identifications. When implemented on the first well, the technology provided immediate results by being the first data acquisition process to recognise that a section was faulted out. Remote well site biostratigraphy also creates a verifiable record, making it possible to quality-control biostratigraphic interpretations; it also frees up space on the rig and improves health and safety for biostratigraphers. Delays in file transfers from the rig to the office are being addressed by reducing the size of the image files by discriminating the fossils from the background.