Earth Notes: Fire and Archaeology

Jul 26, 2017

Wildfires in the West have gotten bigger and more intense over the last 40 years. The amount of land area burned has increased six-fold. On the Colorado Plateau, fires strip away plant life and open up a window to the past, revealing information from thousands of years ago.

A fire-revealed archaeology site
Credit Kaibab National Forest

A landscape suddenly stripped of vegetation can expose ancient archaeological features previously hidden from view. For example, archaeologists are seeing bigger residential sites than they’ve seen before. Fires also uncover more subtle evidence of early farming—like terraces, checkdams and garden walls—along with depressions that could be special features called kivas.

This post-fire evidence is giving a much fuller picture of ancient daily life, land use and ecology. But fire can also leave sites open to substantial collateral damage.

With the most intense fires often occurring just before summer monsoon rains, fragile sites can flood and be more vulnerable to wind erosion.

And there’s a more sinister threat. Archaeologists with the North Kaibab Ranger District of the Kaibab National Forest often see looters moving into freshly burned sites, illegally removing artifacts and destroying our ability to learn about past cultures and civilizations.

So, fire’s effects are a double edged sword, and one that merits more watchful eyes.