ON A RECENT stroll along a deserted Scottish beach, I couldn鈥檛 resist taking a few of the stripy, egg-shaped pebbles that littered the shore. These will look nice in my garden, I thought as I popped them into my pockets. The words 鈥渆co鈥� and 鈥渧andalism鈥� never entered my head.
That was until I heard about 鈥済eoconservation鈥�, a growing movement to give the Earth鈥檚 rocks the same kind of protection as rare animals or museum pieces. Some scientists claim that collecting pebbles and gathering fossils are just as damaging as digging up wild flowers or collecting wild birds鈥� eggs. The world鈥檚 unique geological formations are increasingly under threat, they say, buried under building developments, hidden behind coastal defences, submerged under landfill and swept away by increasingly unpredictable weather. Even geologists have played their part: careless coring and sampling has left many important sites peppered with holes. Now, say geologists, it鈥檚 time to give rocks the respect they deserve.
You might think that being a planet made almost entirely from rock, the Earth would have plenty to go round. But geoconservation isn鈥檛 about protecting any old rocks. What matters is the information they contain. 鈥淕eology enables us to understand the evolution of the Earth we live on,鈥� says Chris Cleal of ProGEO, also known as the European Association for the Conservation of the Geological Heritage. From working out how oceans form and what makes a volcano blow to finding out when life arrived on Earth and what the weather was like 200 million years ago 鈥� rocks have recorded it all.
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Stockton Bar near Salt Lake City in Utah is a case in point. To the untrained eye it is just a pile of sand and gravel, but to a geologist it is the equivalent of a very rare book. During the last major ice age, Stockton Bar was created by the waves and currents of Lake Bonneville, a gigantic freshwater lake that covered much of western Utah. Today the remnants of this lake form Great Salt Lake, but ice age conditions are recorded in features like Stockton Bar. 鈥淚t offers an invaluable opportunity to study climate signals such as temperature, extreme conditions, and wind directions and strengths,鈥� explains geologist Marjorie Chan from the University of Utah in Salt Lake City.
Unfortunately, Stockton Bar is also prime real estate. In recent years luxury homes and golf courses have sprung up, making the most of stupendous views over the surrounding plains. Meanwhile, sand and gravel quarries have eaten into other parts of the bar. 鈥淢ining and building on this bar is like ripping the cover off a rare book. Once urbanisation occurs, no one will ever be able to read the book again,鈥� says Chan.
When a geological resource is destroyed, it鈥檚 not just geologists who lose out. Many rock formations are a vital part of an ecosystem. 鈥淕eology is a significant component of habitat,鈥� says Peter Doyle, an independent member of the UK government鈥檚 Joint Nature Conservation Committee. 鈥淩ocks create the soil, which supports the bugs, beasties, plants and animals on top.鈥�
Limestone pavements, like those above Malham Cove in the northern English county of Yorkshire, are an example. Over millions of years the action of ice and rainwater has sculpted the rock there into what looks like a huge chunk of crazy paving. Rare plants like the rigid buckler fern and the dark-red orchid helleborine live in the niche environment created by the cracks in the pavement.
Rocky ground
Britain has around 2900 hectares of limestone pavement, around 97 per cent of which has already been damaged. Changing climate and pollution run-off from farmland are big problems, hastening erosion and adding unwanted nutrients to the ecosystem. The encroachment of quarries is also of concern, but a surprisingly big threat to the landscape comes from gardeners picking up stones for garden rockeries and water features. 鈥淚n this case it wasn鈥檛 major industry that was a threat, but ordinary people collecting rock for their gardens,鈥� says Mike Benton from the University of Bristol, chairman of the British Institute for Geological Conservation.
Despite these problems, the UK is a world leader in rock conservation. Geological jewels are legally protected if they are given Site of Special Scientific Interest status, even if they are on privately owned land. In the US, only government-owned sites like the Yellowstone National Park are governed by strict conservation laws; private owners of sites such as Stockton Bar can do pretty much as they please. Even designating an area of the UK as an SSSI doesn鈥檛 always keep it safe, though, as geologists have found to their cost.
Last summer an amateur fossil hunter shocked geologists by chiselling dinosaur footprints out of Bendrick Rock, a SSSI in south Wales, and offering them for sale on the online auction site eBay. The fossils were later recovered and the collector cautioned by police, but the trackway 鈥� one of the best preserved examples in the UK 鈥� was ruined. What鈥檚 left is still under threat from other unscrupulous, or badly informed, fossil collectors. 鈥淭here is a lack of understanding of the value of geology,鈥� says Jonathan Larwood, who works on SSSI designation at Natural England, the government body responsible for landscape management. 鈥淎 lot of our time is spent encouraging collectors to work with us in a way that doesn鈥檛 damage our geological heritage.鈥�
Australia is having similar problems protecting its rocky treasures. The remote Pilbara region of Western Australia harbours evidence of the earliest life on Earth: its 鈥渆gg-carton鈥� stromatolites are fossilised microbial mats dating back some 3.4 billion years. They hold clues as to how life evolved on Earth and could help in the search for signs of life on other planets, but this vital information is in danger of being lost.
鈥淲e realised that they were very vulnerable because they were close to a major river system and during the cyclone season bits get washed away,鈥� says Kath Grey, chief palaeontologist at the Geological Survey of Western Australia in Perth. What is more, the fossils were also a tempting target for dealers, who could sell them for thousands of dollars at international fossil fairs. Grey and her colleagues opted for an extreme solution. In 1999 they removed the slab containing the best fossils and moved it to the Western Australian Museum in Perth.
Removing important features from their original context is controversial, but in the face of theft, destruction and construction, relocation may be the safest option. Few people worry about the rocks when the bulldozers roll in, says Grey.
So what鈥檚 the future for our geological treasures? National governments can provide some degree of protection, as can international organisations like UNESCO, which encourages countries to create World Heritage sites and Geoparks 鈥� places 鈥渨ith a geological heritage of significance鈥�.
But perhaps the most important tools are education and 鈥済eotourism鈥�. 鈥淧eople appreciate geology more when they understand what it is they have in their backyard,鈥� says Chan. Ironically, gathering fossils can have a very positive effect. 鈥淐ollecting is an important way of getting people involved, and if carried out responsibly it represents very little threat,鈥� says Larwood. Perhaps I needn鈥檛 feel so guilty about my pebbles after all.
