DAMAGE TO ROCK ART FROM POWER PLANT POLLUTION EMISSIONS:

Murujuga, on the Burrup Peninsula and Dampier Archipelago in the Pilbara region of Western Australia. Photograph from newsartnet.com.

From 2020 to 2026 a study was conducted at a location known as Murujuga, on the Burrup Peninsula and Dampier Archipelago in the Pilbara region of Western Australia. This fascinating study was an attempt to discern what, if any, damage to rock art was inflicted by the air pollution emitted from power plants and industrial enterprises.

Petroglyph at Murujuga, on the Burrup Peninsula and Dampier Archipelago in the Pilbara region of Western Australia. Photograph from newsartnet.com.

Amy Stevens (2026) has written about the area and the importance of the abundant rock art found there, frequently citing K. A. Evans (2026). “Murujuga is a sacred cultural landscape of land and sea Country across the Burrup Peninsula and Dampier Archipelago, in Western Australia’s Pilbara region. It contains an estimated 1 million to 2 million petroglyphs, or rock engravings, that tell the story of the relationship between Ngarda-Ngarli Traditional Owners and this landscape over at least 50,000 years. These petroglyphs hold deep meaning for Ngarda-Ngarli, embodying cultural, spiritual, ancestral and environmental knowledge.” (Stevens 2026)

Petroglyph at Murujuga, on the Burrup Peninsula and Dampier Archipelago in the Pilbara region of Western Australia. 1970 Photograph from newsartnet.com (red arrows show details).

“In July 2025, the Murujuga Cultural Landscape was added to the UNESCO World Heritage List in recognition of its outstanding cultural and spiritual significance. This brought renewed attention to Murujuga, “commodities such as liquefied natural gas (LNG). Concerns have been raised that industrial pollution is degrading the rock art.” (Stevens 2026) As it is a site in the UNESCO World Heritage List, there is an international recognition of its importance to all people, and degradation of the rock art is then a concert to all people.

Same petroglyph at Murujuga, on the Burrup Peninsula and Dampier Archipelago in the Pilbara region of Western Australia. 1970 Photograph from newsartnet.com showing missing details.

Indeed, this has been a concern for over a decade. A 2017 paper by John Black studied the color changes that the pollution might cause in the patina of the rock art panels, and did conclude that there was destruction beginning to show. “The art is under threat due to high concentration sof acidic and nitrate-rich pollution from nearby industrial complexes. Maintenance of the outer, rock or desert varnish, layer of therocks is essential for preservation of the art. An increase in acidity of rock surfaces through acid rain and organic acids from nitrate-stimulated microbial growth may alter the mineral composition, integrity and color of the rock varnish. This paper describes analyses of distilled water washings from rocks on Burrup Peninsula compared with rocks collected prior to industrialization. Acidity of rock surfaces has increased from near neutral to a pH just above 4. The increasing acidity has been associated with a logarithmic increase in solubilization of manganese (Mn) and iron (Fe) compounds from the rock surfaces. A theoretical evaluation using electrochemical equilibrium principles confirms that increasing acidity will increase the solubilization of Mn and Fe compounds. Removal of darker Mn and Fe mixed M(II)/M(III) compounds from the outer, rock varnish layer and the relative increase in ferrous oxide and illite/kaolin compounds will result in the rock surface layers becoming thinner, lighter, redder and more white/yellow over time. The impact on engraved surfaces would be expected to be greater because the rock varnish is thinner than on the non-engraved surface rock. Pollution from industry on Burrup Peninsula is likely to destroy the rock art over time.” (Black et al 2017) In other words, Black et al found that aerial pollution was degrading the patina on the rock surfaces, especially within the petroglyphs themselves.

Petroglyph at Murujuga, on the Burrup Peninsula and Dampier Archipelago in the Pilbara region of Western Australia. 1974 Photograph from newsartnet.co.

Stevens (2026) reported on the third annual report of this monitoring program. In her article K. A. Evans stated “today we released the third annual peer-reviewed report of the Murujuga Rock Art Monitoring Program (MRAMP). This government-funded research effort doesn’t resolve every question – understanding a system as complex as Murujuga takes time. The research is undertaken by a team of more than 30 multidisciplinary researchers, and independently peer reviewed by a range of international experts. It is solely written by the researchers.” (Stevens 2026)

Same petroglyph at Murujuga, on the Burrup Peninsula and Dampier Archipelago in the Pilbara region of Western Australia. 2021 Photograph from newsartnet.com (red arrows show damage to the stone).

Stevens (2026) quoted from Evans report that “Earlier monitoring pointed to nitrogen dioxide, the most abundant air pollutant gas at Murujuga, as a possible cause. But our data at the time couldn’t clearly separate its effects from other air-borne pollutants, particularly sulfur dioxide.” (Stevens 2026)

Petroglyph at Murujuga, on the Burrup Peninsula and Dampier Archipelago in the Pilbara region of Western Australia. 1988 Photograph from newsartnet.co.

Evans (2026) stated “This year’s results change that and the acid rain it can produce, as the most relevant factor. The chemistry behind this is well understood: sulfur dioxide reacts in the atmosphere or on the rock surface to form sulfuric acid. This can dissolve the manganese and iron oxide minerals that give the rock varnish its dark color, to create porosity. Several lines of evidence – atmospheric chemistry, rainfall pH and laboratory testing – now point to historic levels of sulphur dioxide from a range of industry and shipping.” (Evans 2026) Known as acid rain this will degrade the patina as well as the rock surface.

Same petroglyph at Murujuga, on the Burrup Peninsula and Dampier Archipelago in the Pilbara region of Western Australia. 2021 Photograph from newsartnet.co.

“Rock, rainfall, and dry deposition pH values argue against present-day acidification of rock surfaces and historically high rates of patina dissolution. However, the elevated porosity values proximal to heavy industry require explanation. Any such explanation must be placed in the context of this ancient landscape. The rocks of Murujuga weathered sub-aerially for thousands to tens of thousands or even hundreds of thousands of years, prior to the introduction of heavy industry from the 1960s onwards. As heavy industry evolved, the fluxes and composition of emitted gases changed. This extended history complicates attribution of the elevated porosity to any specific time or emissions source. Porosity would have formed naturally over the weathering history of the rock. However, elevated porosity within the weathered rind is observed proximal to Dampier, within a region spatially coincident with current elevated concentrations of NO². This association suggests a link between emissions and the elevated porosity. Both NOx, which include NO², and SOx which include SO², are considered reactive gases, which means that they react in the atmosphere to form nitric and sulfuric acids, which can increase the rate of rock weathering.” (Evans 2026)

Petroglyph at Murujuga, on the Burrup Peninsula and Dampier Archipelago in the Pilbara region of Western Australia.  Photograph from newsartnet.com.

“Damage to landscapes such as Murujuga rarely have a single cause. We’re tracking how many factors interact, sometimes over decades. The fourth and final year of this research will focus on the interplay of air quality, rock surfaces and microbial communities. We will also complete the environmental criteria to protect Murujuga in the long term, with a focus on ammonia and ozone, in addition to sulphur dioxide and nitrogen dioxide. However, ongoing monitoring will continue to ensure the protection of the rock art.” (Stevens 2026) This damage has accumulated over time, and perhaps will hopefully be prevented in the future. This is, however, not the only site by any means where rock art has been damaged by industrial pollution. Indeed, using the findings of both the 2017 study (Black et al.) and the 2026 study (Evans et al.) these processes are constantly at work at many rock art sites, if not all.

Hayden coal generating station, Hayden, Colorado. Photograph by cpr.com.

One site that I know well, here in Colorado, is not far from the Hayden Power Plant in Hayden, Colorado. This is a 465 megawatt coal generating station operated by Xcel Energy Company. This is quite near the Hayden pictograph site which is found along Highway 40. As the photographs show, the rock face here is extremely degraded.

Pictograph panel near Hayden power station showing degraded condition. Photograph Peter Faris, 1982.

Equestrian figure from the left side of the pictograph panel near Hayden power station showing degraded condition. Photograph Peter Faris, 1982.

This damage is not just from the shotgun pellets scattered all over the equestrian on the left (seen as faint white spots). The coal plant emissions cannot be doing this rock art panel any good. Wouldn’t it be a lovely surprise to find something happening to rock art that is good for its preservations?

REFERENCE:

Black, John L. et al., 2017, Theoretical effects of industrial emissions on color change at rock art sites on the Burrup Peninsula, Western Australia, Journal of Archaeological Science: Reports 12, 457-462. Accessed online on 29 August 2026.

Evans, K. A. et al., 2026, Impacts of industrial emissions on rock art at Murujuga, Western Australia, Scientific Reports (2026) 16:13805. Accessed online on 29 August 2026.

Stevens, Amy, 2026, Historic sulfur emissions the likely cause of damage to Murujuga rock art: new research, 25 August 2026, https://theconversation.com. Accessed online on 26 August 2026.