Underground Fires: The Hidden Blaze Beneath Our Feet
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Chapter 1: The Enigma of Underground Fires
A few years back, I had the opportunity to visit the Four Corners region in the Southwestern United States for a geological expedition. During one particularly hot August day, we took a break from our itinerary to hike into a remote area and witness a peculiar sight. On the side of a rocky hill, we encountered a dark opening, from which heat and occasional wisps of smoke escaped. Our guides warned us to stay at least 20 feet away from the hole, explaining that temperatures beneath the surface soared above 1,000 degrees Fahrenheit. If the ground were to collapse, we wouldn't even have time to react. This fire had been smoldering for decades.
Coal, when ignited, can lead to underground fires that thrive in low-oxygen conditions, burning along coal seams deep in the earth. These fires aren't always caused by human actions; they can ignite naturally, often started by surface wildfires or lightning strikes.
One notable example is the Burning Mountain Nature Reserve, situated several hours north of Sydney, Australia. Here, an underground fire has been smoldering approximately 30 meters beneath the surface for over 6,000 years. The burn area spans about 10 meters in diameter, with temperatures reaching an astounding 1,832 degrees Fahrenheit. Initially known as Mount Wingen, the cause of the fire remains a mystery, but it's widely believed to have started due to natural factors. However, human activities can also trigger such underground blazes.
The first video showcases the challenges faced by firefighting crews battling a fire in an underground abandoned mine, highlighting the complexities of such situations.
Section 1.1: The Centralia Catastrophe
Centralia, Pennsylvania, has faced a devastating situation for over six decades after an underground coal seam caught fire. The blaze ignited when the town attempted to burn refuse in a garbage dump, which inadvertently spread to abandoned coal mines. Despite numerous efforts by state and federal agencies from 1962 to 1980 to extinguish the flames, they ultimately abandoned the effort and began relocating residents.
As the fire rages below, the ground above becomes unstable, leading to dangerous sinkholes and the release of toxic gases into the atmosphere. This inferno has been burning for 58 years and may persist for another 250 years, consuming the remaining coal reserves.
The situation in Centralia is not isolated; around the world, countless underground fires burn unchecked. The fundamental chemistry behind these fires involves compacted, flammable organic material that ignites at the surface and then spreads underground, where it can smolder for decades or even centuries. In places like Burning Mountain, the heat generated by the fire causes the overlying rocks to crack, creating pathways for gases to escape and fresh oxygen to feed the flames.
Section 1.2: The Threat of Zombie Fires
The same principles that govern coal fires apply to what's known as zombie fires, which predominantly burn peat. Peat, typically found in wetlands and bogs, accumulates under cool, moist conditions where bacterial decay is limited, resulting in soil rich in organic carbon.
However, when peat dries out, the stored carbon can catch fire. Normally, wet peatlands act as firebreaks, but when they become dry, they can become fire-prone areas. Recent years have seen record temperatures in Siberia, which have parched forests and peat bogs, triggering extensive wildfires. If conditions are sufficiently dry, organic-rich soils can ignite and the flames can spread underground, resulting in a slow-burning fire that can last throughout the winter. When spring arrives, these underground fires can reignite, leading to new wildfires.
With rising global temperatures, Arctic peatlands are increasingly at risk of drying out and becoming susceptible to wildfires, including zombie fires. The ability of coal and peat to smolder for extended periods poses significant environmental challenges for the Arctic region, creating a ticking carbon bomb that could release vast amounts of greenhouse gases.
The second video discusses the implications of underground fires in Oregon, specifically the new threats posed by fires burning beneath the surface.