The Dolomite Problem: 2023 year in geo-review

Hello from Austin! With the city shut down due to icy conditions, I thought it a good time to dust off some of my favorite geologic items from last year, including an incredible scientific discovery, an undercovered news story, and, of course, some favorite books. And if this is your first time reading Unearthed, welcome! Here I write about mostly geological topics and other things of personal interest; if you are looking for oil and gas analytics content head to novilabs.com.

Discovery of the year: solving the dolomite problem

The best types of discoveries are when a long-standing, seemingly intractable problem is sliced through with a solution that seems, in retrospect, obvious.

Enter “the dolomite problem”, resolved in late 2023. Dolomite is a rock type similar to limestone, except that magnesium has been substituted for a substantial portion of the calcium within its crystals.¹ The rock dolomite makes up the picturesque Italian mountain range “The Dolomites”, which, prior to the discovery of the mineral dolomite in the late 18th century, were known as “the pale mountains.”²

Crucially, dolomite makes up a huge portion of the world’s oil reservoirs, thanks to the very simple fact that substituting some magnesium for calcium shrinks the size of the crystal. So when a rock that initially was a limestone transforms into dolomite, very small voids are formed — what the oil and gas industry calls porosity.³ Often, huge oil fields, or the most productive layers within an oil field, are found in rock that has been dolomitized.

So what’s the problem? Despite their incredible importance to the oil and gas industry, scientists had been unable to grow dolomite in the lab. And even beyond that, dolomite is much more common in the ancient rock record than in is observed in modern environments. You can understand why geoscientists were puzzled.

Enter Kim et al., who discovered that dolomite can be grown under cyclical conditions. While a dolomite crystal is growing, defects form on its surface. By “washing away” these defects with fluid that has less magnesium and calcium in it, the crystal can resume growing quickly from a clean surface when fluid rich in magnesium and calcium returns. By frequently cycling the fluids in this manner, the study authors induced the dolomite crystals to grow over a million times faster than without the cycles, achieving the first-ever meaningful growth of dolomite in the lab. Bravo!!

So why is this obvious in retrospect? The few places where we find dolomite today include coastal settings, playa lakes, and hydrothermal areas, where fluids naturally cycle strongly occur over days, months, or years. The solution was there all along.

Even more exciting, this “cyclical crystal growth” paradigm may open up new methodologies for growing other crystal types beyond just dolomite. How incredible that riddles from deep time can push us to novel technologies today.

Underworlds: the book to get for your favorite geologist

Stephen Ellcock’s Underworlds: A compelling journey through subterranean realms, real and imagined contains remarkable artwork, photographs, and quotes from geology, mythology, and more. Just check out this remarkable illustration from the 19th century:

From https://wellcomecollection.org/works/wq676my8

For discovery of this book I have to thank Austin’s lovely new book shop, First Light Books, located north of campus on Speedway in the old post office. My wife and I find ourselves there nearly every week, and our pile of unread books has grown notably faster after FLB’s opening. It has a wonderfully curated selection.

Undercovered story of the year: unintentional geoengineering

Ship tracks off the coast of Europe. ACQUES DESCLOITRES/MODIS LAND RAPID RESPONSE TEAM; MARK GRAY/MODIS via https://www.science.org/content/article/changing-clouds-unforeseen-test-geoengineering-fueling-record-ocean-warmth

For decades, we have been unintentionally cooling the planet, with high-sulfur diesel use in ship engines releasing sulfate aerosols that form clouds and reflect sunlight over shipping lanes. With new regulations banning these fuels recently going into place, these cooling effects have been undone. This impact, in combination with 2022’s Tonga-Hunga eruption and the strong El Nino, likely caused a significant amount of 2023’s record warmth.

Exhibit of the year: New Gem & Mineral Hall - The American Museum of Natural History - NYC

Earlier this year I had a chance to go to the new gem and minerals hall at New York’s Museum of Natural History. The exhibit is excellent, combining beautiful specimens with educational context.

I’m always a sucker for local geology content, and the display case for NYC doesn’t disappoint. That garnet in the middle is the size of a canteloupe.

From https://www.amnh.org/exhibitions/permanent/gems-minerals/educator-resources

Memoir, photography, grandfathers and geology

From www.sarahwilsonphotography.com

Dig: Notes on Field and Family is a touching photographic memoir by Sarah Wilson, the granddaughter of famous UT Paleontologist, Charles Wilson. Charles, before he died, gave Sarah many of his slides and photographs from his own field work in Big Bend, an area Sarah had photographed herself. Sarah then revisited that special place in the context of remembering, while documenting present-day paleontological expeditions.

Reading this one really hit close to home with memories of my own grandfather, a chemist who worked for Texaco. Much of my love of geology I trace back to him and my grandmother taking me across the west to national parks. He was a wonderful man.

You can order Dig here: https://www.sarahwilsonphotography.com/purchase-dig-book

Other Books

Departing from the geologic, I thoroughly enjoyed reading the trifecta of Elon Musk, Going Infinite, and The Fund. SBF, Elon, and Ray Dalio are three very different founders but all manage to hit that messianic susceptibility in their followers in one way or another. Elon comes out looking quite good next to the other two.

A few other notables: Cormac McCarthy’s The Passenger. Tom Holland’s translation of Herodotus’s Histories. The Last Samurai by Helen DeWitt. Skunk Works by Ben Rich. The Wager by David Grann. Salka Valka by Halldor Laxness.

That’s it! Here’s to a great 2024.

1. The difference is calcium carbonate vs. magnesium calcium carbonate. Also note, the rock “dolomite” is sometimes referred to as a “dolostone”.

2. Surely this is the most spectacular example of a mountain ranged named after a geologist, thanks to his own discovery related to that range.

3. This is not always the case—the dolomitization process is incredibly complex, and, in some cases, can reduce porosity, but this is the general trend.