— The swirls of hot pink, lime green and turquoise might be mistaken for some kind of abstract expressionist painting if they weren’t so neatly contained within Canada’s national borders. Ditto for the softer pastels of Afghanistan and the streaks of color within the 28 other countries included in OneGeology’s newly unveiled digital map of the planet.
The color-coded global map, revealed last week in Oslo, Norway, aims to do for the Earth's varied geological layers what Google Maps has already done for its surface. Beyond OneGeology’s eye-popping palette, the new effort may have much to say about how the world views what lies below our cities, forests and even oceans.
“Understanding what’s beneath your feet is pretty important if you need to know about energy or mineral resources,” said Ian Jackson, chief of operations for the British Geological Survey and a OneGeology spokesman. The same holds true for understanding earthquakes, mudslides and volcanoes. Even so, he said in a phone interview from Oslo, “the rocks don’t know political boundaries.”
The United Nations Convention on the Law of the Sea requires countries to use bathymetry, or a detailed analysis of the morphology and geology of the seafloor, to settle disputed marine territories. Having a consistent geological map that extends across international boundaries and oceans, then, could be critical in resolving conflicts like the current scrum over potentially oil-rich Arctic regions.
One solution, devised by an ever-growing international consortium, has been to transfer already-existing data from geological surveys around the world to a Web-accessible format that can be easily searched, shared and added to.
Supported by the United Nations Educational, Scientific and Cultural Organization (UNESCO) and nine other international bodies, the project is the flagship undertaking of what has been designated by the UN as the International Year of Planet Earth. When it officially began in March 2007, Jackson said, the goal was to have 10 countries on the digital map in time for last week’s International Geological Congress in Oslo. Instead, 30 countries were fully represented, and the list of participating nations hit 85 on Thursday when India and Sudan agreed to join. The maps are being compiled at a scale of 1:1 million, though many countries are already producing more detailed information.
Dale Setterholm, associate director of the Minnesota Geological Survey, said comprehensive geological maps are most often applied to managing hazards or natural resources such as minerals and water.
“The arrangement of geological materials beneath the surface determines where water collects, where water can move and where it cannot,” Setterholm said. In essence, it defines the locations of aquifers. “We’re constantly, these days, trying to strive for sustainable management of these resources. It’s hard to protect an aquifer if you don’t know where it is and how big it is.”
Broadening one’s geologic horizons through an easily accessible map may pay off in other ways.
“I think the greatest potential for surprise is once we look beyond our own boundaries,” he said. “I might understand the geology of Minnesota pretty well and I’m not likely to find any more surprises there, but if I look across the border into Wisconsin, maybe a feature that I’m looking at is part of a much larger feature that I wasn’t aware of.”
Peter Lyttle, the U.S. Geological Survey’s Program Coordinator for National Cooperative Geologic Mapping and Landslide Hazards, said rock formations can provide other global data such as clues about what the Earth’s climate was like when they were first deposited. Likewise, they can suggest whether they are liable to move again in the near future.
“For instance, if one knows the engineering properties of rock formations along the proposed path of a new gas pipeline, or interstate highway,” he said in an e-mail, “one could plan to avoid rocks and sediments that would slump or fail after construction, or you could avoid putting a new landfill in an area where the underlying rocks are highly fractured or unstable.”
Cooking up a new map of the world
Within the OneGeology project, each country’s geological survey follows the directions of a guidebook dubbed the “Cookbook” and deposits map data on its own Web server or on an associated “buddy” server linked to a common portal in Orleans, France.
In the coming months and years, more sophisticated searches will be available through the portal, along with three-dimensional and even four-dimensional geological models, the latter of which will include the element of time. The site is also accelerating the development of a common Web language specific to geology, known as Geoscience Markup Language, which could allow programmers to incorporate the data into scores of other online applications.
The Minnesota and U.S. Geological Surveys, among the roughly 90 surveyors contributing to OneGeology, have long charted out rock formations to assist engineers and officials with state and national projects. But with the geologic information now available digitally, Lyttle said, anyone can easily download a layer of relevant information, like a county zoning board trying to restrict new home construction over sinkholes or areas susceptible to landslides. With a common computer language, tools and standards, Jackson agreed, previously inaccessible data can be integrated into a seamless whole no matter where the location.
A collaboration among Afghani, U.S. and British geologists, for example, yielded the first-ever digital geological map of Afghanistan. When geologists returned to Kabul after the fall of the Taliban, the whole of the country’s geological map collection “could fit onto a kitchen table,” Jackson said, “and some of it was covered with AK-47 bullet holes.” A color-coded map on the OneGeology site now details the country’s bedrock stratigraphy and age as well as its major fault lines.
As for the color codes, some of the conventions date all the way back to 1815, when British surveyor William Smith first produced a hand-tinted geological map. England’s famous White Cliffs of Dover still show up as green streaks despite their chalky composition, for instance.
A more global view reveals that the green-coded chalk formations extend beyond the British Channel well into France. In OneGeology's map, as well as on many other versions, West Virginia’s coalfields appear as more somber grays. In northern Italy, a horizontal strip of pale yellow defines the Po Valley and its relatively recent sediments that have swept down the Alps. And in Sicily and Japan, angry red dots denote rocks of volcanic origin.
The evidence for these identifications may come in the form of bore holes drilled deep into the ground, naturally exposed bedrock, or even a new highway that cuts into a hillside. As a young field geologist, Jackson said he visited graveyards so he could peer at the exposed layers within six-foot-deep plots otherwise covered in grass. But even with the evidence in hand, he said, “no two geologists will agree on the interpretations.”
With the global initiative as a guide, however, greater access to varying opinions could help color researchers’ thinking about their own patch of ground.