Welcome to the PerGeos Use Case Gallery

Knowledge of shale pore structure characteristics is crucial to understand gas
storage and seepage mechanisms. Organic matter (OM) pores are considered
the most important pore type in shale, and one of the currently significant
research questions focuses on the spatial distribution and connectivity of OM
pores. To answer this question, typical OM‐rich siliceous shale samples from
the Lower Silurian Longmaxi Formation were comprehensively investigated
usin... Read more

The task of reliable characterization of complex reservoirs is tightly coupled to studying their microstructure at a variety of scales, which requires a departure from traditional petrophysical approaches and delving into the world of nanoscale. A promising method of representatively retaining a large volume of a rock sample while achieving nanoscale resolution is based on multiscale digital rock technology. The smallest scale of this approach is often realized in the form of working with sev... Read more

Understanding transport mechanisms that govern two-phase flow in fractured porous media has direct implications for natural and industrial processes such as extraction of hydrocarbons from fractured reservoirs, geologic sequestration of CO2, or fluid flow through aquifers.

We present the results of a systematic pore‐scale experimental investigation of two‐phase oil/brine flow through a miniature water‐wet, fractured sandstone core sample. X‐ray microtomography is employed to ge... Read more

Optimization of production from shale reservoirs requires understanding of rock properties over a range of scales.

Multiple imaging techniques can be combined to determine the nature, connectivity, and wettability of nano-scale pore systems as well as the underlying mineralogy and organic textures that control reservoir behavior and the propensity of the matrix to fail and to contain expulsion cracks. The current study demonstrates new capabilities in integrated multiscale and time-res... Read more

This study investigated the influence of compaction on the variation mechanism of petrophysical properties and the relative permeability of unconsolidated sandstone.

Firstly, triaxial mechanical experiments, CT scans, and mercury injection experiments were performed to analyze the microstructural characteristics and the macroscopic mechanism of changes in the petrophysical characteristics under different pressure. Secondly, a modified permeability test approach was adopted on reservoir... Read more

Advances in imaging have made it possible to view nanometer and sub-nanometer structures that are either synthesized or that occur naturally. It is believed that fluid dynamic and thermodynamic behavior differ significantly at these scales from the bulk. From a materials perspective, it is important to be able to create complex structures at the nanometer scale, reproducibly, so that the fluid behavior may be studied. New advances in nanoscale-resolution 3D-printing offer opportunities to ach... Read more

Technological advances and energy demands have made tight sandstone reservoirs worth to be exploited. Tight reservoirs are characterized by low porosity and permeability and strong heterogeneity, especially considering the extensive development of nanometer-scale pore throats or the wide-ranging PSD. Previous studies reveal that the PSD and pore-throat structure have a more direct effect on the storage and transport performance of tight sandstone reservoirs than porosity and permeability. Dif... Read more

Generating an accurate reservoir model is of critical importance in forecasting the lifespan of hydrocarbon reservoirs and estimating the efficiency of carbon capture and sequestration. One critical parameter controlling the flow of fluids within subsurface reservoirs is the fraction of effective or connected pore spaces in the reservoir. […]

To quantify the connectivity of the pore space, it is therefore necessary to combine high resolution visualization of pore spaces with bulk... Read more

During a Geologic Carbon Storage process, supercritical CO₂ (scCO₂) is subjected to a series of dynamic and static conditions where the relationship between pore geometry and the trapped scCO₂ curvature remains to be established. To mimic the dynamic process, two sandstones, Bentheimer and Nugget, were subjected to two successive drainage and imbibition (D-I) cycles and X-ray computed tomography scanned at each residual state to capture the wettability evolu... Read more

Premier, COREX has been providing core analytical services to the oil and gas industry for more than 30 years. Within the last decade it has augmented its rock core investigations by sending samples for analysis approximately every week to Nikon Metrology’s centre of excellence for micro-focus computed tomography (micro-CT) in Tring, Hertfordshire.

Drilling for oil or gas is an expensive business, whether offshore or on land, so it is essential for E&P (exploration and producti... Read more

Laboratory Experiments on rock specimens are designed for understanding and characterizing subsurface environment, quantifying potential recovery, and tuning fluid flow models in porous media. The spatial variability and reservoirs’ heterogeneities predicate acquiring expensive cores from different locations. These experiments are mechanically and petrophysically destructive and cannot be repeated or extended on the same core. Replicating core samples with 3D-printing technology innovation ... Read more

Relative permeability and capillary pressure are key properties within special core analysis and provide crucial information for full field simulation models. These properties are traditionally obtained by multi-phase flow experiments, however pore scale modelling has during the last decade shown to add significant information as well as being less time-consuming to obtain. Pore scale modelling has been performed by using the lattice-Boltzmann method directly on the digital rock models obtain... Read more

Up‐scaling the elastic properties of digitized rock volumes as obtained from X‐ray computer tomography (CT) imaging via computer simulations has the potential to assist and complement laboratory measurements.

This computational up‐scaling approach remains a challenging task as the overall elastic properties are not only dependent on the elastic properties of individual grains but also on the hardly resolvable pore spaces between adjacent grains such as micro‐cracks. We develop ... Read more

Fractures are crucial for unconventional hydrocarbon exploitation, but it is difficult to accurately observe the 3D spatial distribution characteristics of fractures. Microtomography (micro-CT) technology makes it possible to observe the 3D structures of fractures at micro-scale. In this study, micron-CT scanning is conducted on multiple mud-shale samples of source rocks in the Permian Lucaogou Formation, Junggar Basin. The Avizo software is applied to process and segment the micron-CT images... Read more

With advancements in additive manufacturing, now 3D-printed core plugs can be duplicated in order to replace natural rock samples. This can help us to control their parameters to be used in different types of experiments for model verifications.

However, prior to such substitutions, we should ensure they can represent natural rock samples through characterizing their physical properties. In this paper, synthetic samples made up of gypsum powder are 3D-printed and then characterized for... Read more

Coke deposition during crude oil in-situ combustion (ISC) is an important phenomenon that significantly impacts the pore topology and permeability.

In this study, X-ray computed microtomography and a specific image processing procedure were used to reconstruct the micro-tomographic images of packed beds with coke deposition. From the reconstructed images, the microstructural parameters related to the transport were analyzed, such as the effective porosity, the constrictivity and the ge... Read more

X-ray micro-CT imaging is becoming an integral part of rock characterization processes. Large data size, user bias, and accuracy of the results are some of the challenges associated with analyzing micro-CT images of rock samples.

In this article, the PerGeos Digital Rock Analysis software is demonstrated to analyze the full micro-CT dataset of a Berea sandstone mini plug. The analysis is done in blocks using a PerGeos recipe (i.e. a macro) and a block-processing script. The results are... Read more

We introduce here some techniques to visualize and process large data, mostly targeting the high resolution data acquired by Heliscan microCT.

The data is considered as “large” in the sense that its size exceeds the size of the GPU memory and/or the size of the RAM of the machine.

The following workflow:

• Segmentation
• Porosity / Connected porosity determination
• Pore separation / Pore Size distribution
• Grain size distribution

Imagery produced from FIBSEMs (Dualbeams) provides users with unique data in terms of resolution and sample size that are not available with other techniques. Despite the power of this analytical approach, some limitations in quantifying the textural data restrict the accuracy of data obtained from FIBSEM images.

These limitations are derived from artifacts that occur during the acquisition of the data. Collecting data using a FIBSEM is a destructive, serial sectioning technique. A thi... Read more

A key benefit to obtaining digital imagery data is the ability to use all parts of the imaged sample for characterization purposes-not just what you have time to explore manually. This is especially the case with large datasets that are created during acquisition of 2D mosaic images or Whole Core CT imagery.

In these cases, a representative area or volume of material has been obtained. The next step will be to extract features, like porosity, for analysis.

But, what else can we ... Read more

Pore-scale two-phase flow modeling is an important technology to study a rock’s relative permeability behavior. To investigate if these models are predictive, the calculated pore-scale fluid distributions which determine the relative permeability need to be validated. In this work, we introduce a methodology to quantitatively compare models to experimental fluid distributions in flow experiments visualized with microcomputed tomography.

First, we analyzed five repeated drainage-i... Read more