Tuesday, 1 July, 2025 / Edition 65

A consistent theme in geology is the inability to see what we’re working with in the subsurface.

We tend to get disparate, often sparsely sampled data, and I know I have sometimes wished for Superman’s x-ray vision capabilities to better understand what’s down there and what it means. Imagine if, instead of x-ray vision, we were able to harness the energy of a supernova explosion to help us more accurately map out the subsurface…. maybe we can! Let’s take a look.

Sarah Compton

Editor, Enspired

Mapping Density Differences with Muons

Nimneth X/Shutterstock.com

Canada-based Ideon Technologies is using muon tomography to help companies such as Rio Tinto and BHP map subsurface orebodies, among other applications.

It’s elementary, dear Watson: A muon (bonus for people who know if it’s “mooo-on” vs “m-you-on”) is similar to an electron in that it has a charge of negative one and is an elementary particle. It’s much larger (more than 200x) and is unstable, lasting only 2.2 microseconds compared to an electron’s more than 6.6×10²⁸ years.

Phenomenal cosmic power: The muons that end up on Earth’s surface are thought to be decay products created when cosmic rays, such as those from a supernova, collide with atmospheric particles. So, they are basically space trash.

Muons are detectable nearly one kilometer below the surface through solid rock and water.

If you squirmed a little upon realizing that the decay product from a collision of space rays and our atmosphere is hurtling through your body RIGHT THIS SECOND, you’re not alone, but fear not because your body can take it 🤓. Probably.

The very, very basics: Anyway, muons interact with the subsurface in different ways depending on the composition and density of the material through which they travel.

The denser a material is, the more likely muons are to interact with it, decreasing the amount that will reach a detector.

In other words: We can use space trash (muons) to detect density differences in the subsurface as long as it’s shallow enough and we can find a way to get a detector down there. That last part is where Ideon comes in.

Delivering the goods: In March, the company boosted exploration targets for a Canadian mining company—during the Yukon winter 🥶 —providing density maps at meter-scale resolution covering more than one billion cubic meters down to 600 meters depth.

If you are interested in more information about muon application in geosciences, check out this paper.

Sponsored

TGS's Carl Neuhaus at URTeC

Carl Neuhaus, VP of Well Data Products at TGS, outlines recent updates to the TGS well data analytics platform, including the integration of new lease data through a partnership with Oseberg.

Energy Storage Via Phase Changes

Leigh Prather/Shutterstock.com

When most of us hear the word “battery,” we think of a small piece of tech that has liberated us from the cord and generally stores energy through chemical potential.

Some engineers have taken the concept, though, and applied it to heat and/or heat storage.

Hot and cold: What’s one of the best ways to store heat? Ice! Of course.

Stay with me here. What initially seems counterintuitive is a bit brilliant and harnesses all the things us geoscientists love: phase changes, efficiency, and bodily comfort while indoors.

Driving the news: Engineers have turned geothermal on its head a little and devised a method to optimize A.C. off-peak demand times to create and store ice overnight for cooling use during the day.

• It’s called a thermal battery system and functions based on the simple fact that the phase change from water to ice (and back) act as a temperature storage action.

How it works:

• During the night, the air is cooler and demand for A.C. is low, so the system uses that cooler air to initiate a phase change of stored water to ice.

• During the day, that ice is utilized to cool warmer air in buildings and data centers.

Why it matters: It’s estimated that A.C. accounts for seven percent of electricity consumption and three percent of carbon pollution globally.

As we geoscientists continue to search for ways to power our world, it’s worth remembering that electricity isn’t the only thing that can be optimized: sometimes tackling the problem head-on is more efficient than hunting for workarounds.

To learn more about how thermal batteries work: go here or here.

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