Among the oldest examples of cave artwork within the US are on the partitions of Dunbar Collapse Clarksville, Tennessee—50 miles northwest of Nashville. Courting again round 800 years, these embody petroglyphs carved into the limestone and pictographs drawn in charcoal that had been recognized within the early 2000s. Some have geometric, summary types—similar to concentric round shapes—whereas others characteristic human figures or presumably signify beings associated to non secular observe. The cave is believed to have been a sacred house for Indigenous folks in the course of the Mississippian interval, spanning from roughly 500 to 1,000 years in the past. Archaeological research have revealed indicators that the usage of the cave by people goes again even additional—going down over tens of 1000’s of years—from traces of the extraction of its mineral assets to proof of the care of the useless. The cave, stretching eight miles underground, is now a part of Dunbar Cave State Park.
In February, extreme flooding from heavy rains utterly submerged the cave artwork. Dunbar Cave State Park officers said that it was the very best flooding within the cave on report, “a number of ft increased” than one other main flood in 2010 and “the third such occasion in lower than one yr”. Photographs they posted on-line confirmed the aftermath: mud was caked on all sides of the cave, together with the ceiling, with a number of bats discovered drowned. Restoration of the location’s broken infrastructure is now underway to be able to reopen the cave for public excursions. In the meantime, archaeologists have been assessing any harm to the cave artwork, as this was the primary recorded time it had been utterly lined throughout a flood.
Entrance to Dunbar Cave Picture: David Duplessis © TennesseePhotographs.com
Based on data shared by the Tennessee Division of Atmosphere and Conservation (TDEC), its Division of Archaeology (TDOA) has in contrast high-resolution images that had been taken of the artwork in 2014 to these taken after the flooding. This evaluation confirmed that there have been no indicators of the pigments having degraded or undergone structural harm from water and sediment speeding into the cave. TDOA additionally performed a non-destructive analysis of any adjustments within the artwork’s elemental or mineralogical nature utilizing fibre-optic reflectance spectroscopy and transportable X-ray fluorescence spectroscopy. This examination was in comparison with research achieved in 2016, and it revealed no detectable adjustments within the artwork’s chemical composition.
As above, so under
Though the cave artwork doesn’t seem to have been harmed, TDOA is planning common monitoring for the potential influence of flooding because it turns into a extra widespread prevalence. This might have oblique results on the artwork as properly, if the cave atmosphere adjustments as a consequence of issues like will increase in ambient moisture and humidity. As a part of this care, TDOA and Tennessee State Parks are persevering with their ongoing work with Indigenous descendant communities, together with the Japanese Band of Cherokee, within the preservation of this archaeological web site.
“Defending and stewarding irreplaceable archaeological options like that at Dunbar Cave is among the many most vital work that we do,” says Phil Hodge, a state archaeologist and director of TDOA. “And it’s greater than merely preserving historical pigments on a limestone cave wall; it’s about preserving the voices of Indigenous individuals who used this cave and held it sacred for 1000’s of years, and who stay linked to it within the current.”
Sacred shapes: the partitions of Dunbar Cave—believed to have functioned as a non secular house for Indigenous folks 500-1,000 years in the past—are adorned with each geometric types and depictions of people
Picture: TSP Advertising and marketing archives
Tennessee State Parks can also be partnering with the US Geological Survey and the TDEC Division of Water to check the hydrology of the watershed within the space in an try to find out long-term options. Dunbar Cave is only one characteristic in a “karst” area—formed by the dissolution of its limestone bedrock into caves, sinkholes and different options. (Tennessee is without doubt one of the most “karstified” areas of North America, and the state has 1000’s of identified caves.) This causes a definite relationship between water and a really porous floor; water has at all times been a part of Dunbar Cave, however by no means at such excessive ranges and so fast-moving.
How water is managed above influences every thing that occurs underground, and local weather change—in addition to improvement of the constructed atmosphere—can have a major influence on not solely the way forward for the artwork at Dunbar Cave but additionally on its subterranean ecological habitat, a haven for uncommon animals like endangered gray bats, blind cave crayfish and southern cavefish. Restoring points of the atmosphere surrounding the cave, like wetlands, might assist mitigate harm from future main storms. For instance, a current proposal from state officers thought of returning a synthetic lake at Dunbar Cave State Park to its pure and extra sustainable state as a free-flowing stream, which might higher handle an growing frequency of flash flooding. Nevertheless, the Clarksville Metropolis Council voted in January to protect the lake, which is used to irrigate an area golf course.
Inside Dunbar Cave Picture: TSP Advertising and marketing archives
“We’ve got to ask: can we higher educate the native public in regards to the significance of watersheds and karst?” says David Britton, the park supervisor at Dunbar Cave State Park. “On this a part of the nation, our above-ground world is intrinsically linked to the world under our ft. Good stewardship ensures concord and safety of not simply cultural treasures just like the cave artwork, but additionally all the ecosystems that exist in caves. Our day by day actions on the bottom can have devastating penalties, even when we will’t instantly see the results.”
After the flooding earlier this yr, though some mud gathered in Dunbar Cave’s passageways, a lot of the influence was on its infrastructure. Two massive boardwalks had been broken after being dislodged by the floods. One in all them gives customer security in a moist space of the cave, whereas the opposite prevents harm from foot site visitors in an archaeological space. These are being reconstructed by a restoration workforce, in a method that’s sustainable and meant to maintain them from breaking free once more in future flooding.
The rebuilding of the boardwalks is being addressed earlier than guided excursions can restart. Excursions are normally held seasonally from Might to September and have included the cave artwork. They’re the one such alternative for the general public to see Mississippian cave artwork on this uncommon place, the place an underground cultural historical past and ecology are each cared for collectively.
