Digital Exploration and Analysis of Rock Samples: Webinar by Wiley and ThermoFisher Scientific, September 16, 2025: Review & Summary

         This was a fast-paced webinar with six presenters of different kinds of digital analysis of rock samples for different applications. The presentations were brief. One was in Korean, but the figures are useful. I have lots of experience examining rock samples with a binocular microscope with small magnification, as commonly used in oil & gas mudlogging. I have seen images through an SEM while at university, as well as completing classes in crystallography, mineralogy, and microscopy for optical mineralogy analysis. These digital techniques go into much greater detail for much deeper rock sample analysis.

 

Introduction

     The introduction presented by Luigi Raspolini of ThermoFisher Scientific describes the different techniques analyzed. These include characterizing rock morphology and flow of pressurized fluids through rock, microscopy, computer tomography, and different kinds of spectroscopy. Morphological characterization through computer tomography, SEM microscopy, and spectroscopy was explored. Image segmentation and analysis are used in these techniques to measure physical properties. Visualizations can be aided by AI and deep learning. Avizo software is used to measure parameters. Porosity and fluid flow (permeability) can be measured in projects where optimum porosity is desired, ie, oil & gas extraction, CCS, hydrogen, and geothermal. Pore space is one parameter that is scanned.

  

Morphology and Fluid Flow

     Pore-scale visualization is enabled by digital analysis techniques. Presenter Gidon Han of the Korean Institute of Geoscience and Mineral Resources shows X-ray micro CT images in 2D and 3D, where pore space can be examined in detail.

     The next presenter, Nihal Darraj, CCS Researcher at Imperial College London, UK, examines the Edwards Brown Dolomite in the millimeter to centimeter scale for CO2 storage in heterogeneous rocks. Drainage and imbibition were observed to determine trapping efficiency. Trapping is variable in different parts of the rock. Small-scale heterogeneity plays a crucial role in trapping.  

 

Multi-Channel Visualization of Spectroscopy Data

    Energy dispersive X-ray spectroscopy (EDS or EDX) is presented by Luigi Raspolini, PMM at Thermo Fisher Scientific. These techniques are used to determine the chemical composition of rock samples. The source for EDX is high-voltage electrons. He gives a movie of how it works. The technique is used to determine the elements present and their ratio.

     The next presentation, by Prof. Zhaoyang Ma, Assistant Professor @ Nanjing University, China, involves CT and SEM-EDX scans of gray and red sandstones where visualization of 3D pore structure is the goal. Results show that supercritical CO2 (sCO2) alters the mineralogy of the sandstone, resulting in calcite reprecipitation, feldspar dissolution, and more. Mineral dissolution can increase porosity. CT and SEM-EDX measure chemical composition and mineral distribution, and mineral volume fraction. The examples given are in basalt rock.

 

Dual Energy Computer Tomography (DECT)

    This technique, presented by Alex Hall, PhD, Avizo Product Expert at Thermo Fisher Scientific, is valuable for oil & gas exploration and analysis. A core or plug is placed in a CT scanner. A sample is measured at two peak X-ray intensities. Mineral distribution in the core or plug volume is measured. The technique can be useful in mining as well.

 

Laser Ablation Laser Ionization Time of Flight Mass Spectroscopy (LALI-TOF-MS)

      This was presented by Ellen Williams, EVP Business Development at Exum Instruments. LALI-TOF-MS enables the creation of millimeter-scale elemental maps. Useful in oil & gas and minerals exploration. The technique destroys a small part of the sample, but not too much. Elemental maps in the size range of 5-150 microns can be created. Powdered samples can be examined with this technique.

 

Q&A Session

DECT – what materials are used to calibrate? A sample is measured at two peak X-ray intensities at known densities. Different materials can be used. Different peak energies might be chosen for different rock samples. Presented as a linear log of the most common elemental composition that can be compared to other well logs.

Can Avizo also work with Micro-CT data? Yes. Different visualization capabilities for different types of data.

Can Avizo run on a laptop? Yes, but better results are obtained with a powerful graphics card with at least 12GB of video memory and adequate system RAM (48-68GB of RAM per 10GB of data is a rule of thumb).

How does Avizo utilize AI? AI works on the image side via neural networks for denoising, object segmentation, and material segmentation. Training via Avizo is getting better for image characterization. It allows for the creation of AI models.