A feeling for poetry in the glory of things

Another Life: Along the hillsides, rocks are giving way - boulders heaved aside, bedrock carved out with jack-hammers to create three-bedroomed niches with a view.

In the valleys, a drumlin here, an esker there is disembowelled for gravel; a handy river-bed of mountain cobbles is scooped out for hard-core. Seldom is geology so rawly and intimately exposed as in the west coast's current building boom.

But the rocks endure, as mountains, cliffs and crags, intransigent outcroppings, scatters of erratics (lonely boulders, far from their source, abandoned in the wake of flowing ice). If only, in this sudden and resurgent local utility of stone, there was more knowledge of it, more feeling for the drama and hugeness of its past and the special, local chapters in its story.

Much of it is quite mind-blowing, in time-scale and physical events. To be told that there are 2,000-million-year-old traces in some of Mayo's rocks, or that what is now Ireland was once in two halves, rammed together on a line from Clogher Head to the Shannon, can be hard to relate to the modern landscape in any meaningful way. Only when the last lot of ice ages start, a mere two million years ago, can the sculpture of mountains and valleys, the gouging and grinding of bedrock, the dumping of debris from bulldozing glaciers, begin to be matched at all comprehensibly to the view.

Could any of the island have survived the repeated ebb and flow of glaciation over those two million years? It's accepted that many mountain peaks - Mayo's Mweelrea for one - stuck up above the last ice sheets as bare, frozen nunataks, an Inuit word. But the idea that any part of the western lowlands - and soft, limestone lowlands, at that - could offer such an "untouched" archaic surface seems truly astonishing.

It's just 20 years since a geologist's borehole in a sand-pit at Pollnahallia, between Headford and Tuam in east Galway, came up with pollens from a lost, pre-glacial vegetation - a warm, wet landscape in the late Tertiary era, dominated by swamp cypress and full of trees and shrubs that have long since vanished from Europe's native list.

Trinity's Prof Pete Coxon, Pollnahallia's prime investigator, last month led 60 Irish and British scientists to the spot as part of a major tour of western sites from Clew Bay to the Burren. As chairman of the Irish Quaternary Association, he had edited a field guide for the tour, and it's in this that he spells out his evidence for believing that at least three square kilometres of the surrounding limestone surface, and possibly a lot more, has survived two million years, complete with its ancient organic clays and silts.

The field guide*, which brings the region's quaternary research up to date, has other fascinations for landscape detectives prepared to wrestle with the technical bits: along with Pete Coxon, contributions by Mike Simms on the weird sculpture of the limestone shore of Lough Mask and the mechanics and topography of the Burren are particularly readable.

The guide comes on the heels of the recent publication, by the Royal Irish Academy, of the proceedings of an international conference in Dublin Castle in 2002, Natural and Cultural Landscapes - the geological foundation. Edited by Matthew Parkes of the Geological Survey of Ireland, it is a hefty document at 320 pages. It is available at print cost at http://www.ria.ie/committees/ geosciences/index.html.

The conference was often a passionate one and took a new coinage to its heart, "geodiversity", meaning the widest, perhaps Gaian, link between humans, animals, plants, rocks and landscape.

Many delegates warmed to Seamus Heaney's proposal that their job, no less than that of poets, is "giving glory to things just because they are". In fact, he told them, "there is a kind of artistic detachment and visionary perspective about geological discourse that match the scope and fetch of poetry itself".

This must have encouraged the conference's Dublin Declaration - a commitment to spreading the word about the island's geological heritage and fighting for its conservation (prime sites on private land, for example, need the same protection as those of archaeology and architecture). Since then, the lively Earth Science 2000 group, with a website hosted by the Ulster Museum, has become the focus of an Ireland-wide educational drive. It will ultimately extend its free magazine, through sponsorship, to schools and libraries in the Republic. In the meantime, it can be downloaded at http://www.habitas.org.uk/es2k.

The Quaternary of Central Western Ireland is available, priced €20, at http://www.tcd.ie/Geography/IQUA/Index.htm