Advances In Imaging And Analysis For Petrology: Whats In The Kitchen Sink?

Geologists now have a large array of instruments at their disposal for microscopy and microanalysis. The nature of geoscience materials, and the variety of petrological problems mean that advances in lab-based tools must be matched by flexibility. Multi-scale, multi-modal analysis is essential for metamorphic petrology, where critical understanding of micro-to-nano scale features must be placed in a broader context. Essential in this process is not just the use of class leading microscopes, but the ability to link information across several orders of magnitude in 2 and 3 dimensions, and share data between laboratories that have different instruments. It is currently a very exciting time with new technology either specifically tailored to geoscience, or perfect for its requirements. In light microscopy we now have the ability to digitise full thin sections in a way never before possible, paving the way for future developments in quantitative petrography, advanced analytics and automated project workflows. The ability to apply machine learning segmentation to large sample volume has already seen a big take up in industry workflows, and alongside grain size and orientation analysis has the ability to change the way we go about research projects. Scanning electron microscopy (SEM) has always seen heavy use in petrology, and the latest generation of instruments and detectors allow for large amounts of connected data from metamorphic samples. Quantitative analysis is now going to be the norm with the latest generation of EDS and WDS detectors allowing for PT calculations and trace element profiles straight from thin section mapping, and geochemistry linked directly to EBSD. Analytics in 3D have always provided some of the most engaging images of geological samples, increasingly these images come with additional quantitative information. Non-destructive X-ray imaging (XRM and CT) can now scan larger volumes at higher resolution, ideal for heterogeneous samples. Lab-based diffraction contrast tomography (DCT) now enables rapid crystal orientation analysis in all crystal systems alongside standard 3D imaging. Key structures identified in 3D can now be excavated and analysed using correlated Crossbeam Laser instruments, allowing for rapid sample prep followed by nano scale imaging combined with EDS and TOF-SIMS.