KANE COUNTY, Utah (ABC4) – Fires across Utah start by nature or humans. They start and spread all across Utah’s differing terrain, especially as the temperature starts to rise.

But did you know Utah has fires not only throughout the state’s surface land but beneath the surface too? Geologists say it was started by “spontaneous combustion” and it’s still burning today.

Southern Utah is known for its beautiful landscapes, national parks, and hot temperatures. 

In Kane County, a blazing hot area located north of western Lake Powell is dotted with heat-related places. Warm Creek, Burning Hills, Smoky Hollow, Blackburn Canyon, and Smoky Mountain are a few. 

Courtesy: Utah Geological Survey

According to the Utah Geological Survey (UGS) research conducted by Marshall Robinson, these place names actually signify underlying heat sources that have nothing to do with the air temperature.

One of these places in Kane County, Smoky Mountain, has actually been burning hot for hundreds, and maybe even thousands of years. 

An actual fire beneath your feet:

Atop Smoky Mountain, you won’t find actual flames, but there is an actual fire beneath your feet. 

This underground fire is known by geologists as the “Big Smokey Fire,” the Utah Geological Survey shares. It is burning, or at least smoldering, underground. Large fissures, or cracks in the ground feed oxygen to this underground fire allowing it to continue to burn all these years.

“Expectations may be high to see the gaseous fumes from this fire venting from the cracks, but realize this is only possible when temperatures are near or below freezing,” as stated on the Utah Geological Survey’s website. 

Even when you can see the smoke or fumes, you can see a scene similar to a volcanic area, such as Yellowstone National Park. 

Courtesy: Utah Geological Survey

UGS says an underground coal seam, or seams, fuels the fire beneath Smoky Mountain. 

Smoky Mountain’s numerous coal seams are interbedded among 1,000 feet of Cretaceous-aged mudstone and sandstone known as the Straight Cliffs Formation, the survey shares. “The Straight Cliffs Formation was deposited approximately 80 to 90 million years ago when the area was encroached upon by a fluctuating body of water called the Western Interior Seaway,” as stated by the Utah Geological Survey. 

They say the fluctuating sea level caused the layers of mudstone, sandstone, and coal found in the cliffs and ledges of Smoky Mountain to deposit. 

“A thick layer of sandstone dominates the uppermost cliffs of Smoky Mountain and overlies a poor foundation of soft mudstone,” as stated by the survey. 

Ground cracks near Big Smokey Fire run parallel to the cliff edge and are likely due to the erosional undermining of the cliff’s mudstone base. 

According to the survey, other cracks developed as the underlying coal seams burned out and reduced to ash, leaving little to no support for the overlying sandstone. 

The cracks will eventually propagate to the surface. The Utah Geological survey says it is unlikely that a lack of oxygen will naturally lead to the fire’s demise.

How did the fire start in the first place?

According to the Utah Geological Survey, spontaneous combustion or a lightning-sparked wildfire are the two probable candidates for the start of the Big Smokey Fire.

The fire is still burning today, despite attempts to extinguish it. 

The Utah Geological Survey says on two separate attempts, once in 1967 and again in 1968, the U.S. Bureau of Mines tried to extinguish the Big Smokey Fire with water and other fire retardants. 

They even had bulldozers and excavators fill the cracks in the earth with rocks and dirt, hoping to smother it. 

As proof that the fire still burns, new cracks have popped up on the surface since attempts to extinguish it.  

Because the Smoky Mountain fire is a coal fire, it is a naturally occurring phenomenon. When coal begins burning, it often burns until there is none left, or the oxygen source is cut off.

The survey says it is likely the fire will continue to smolder until the coal is gone from this location.  

The land is now a part of the Grand Staircase Escalante-National Monument, which preserves the land for non-destructive scientific studies.

An old underground burning fire might seem like an anomaly but the Utah Geological Survey says there are actually thousands of these uncontrolled fires throughout the world. Utah even has 11 uncontrolled coal seam fires concentrated in Kane, Emery, and Carbon counties.