Nov. 18, 2004 — Every year, the U.S. gives birth to millions of new cars that require mining almost enough earth to fill Meteor Crater in Arizona, a hole 600 feet deep (183 meters) and three miles (5 kilometers) in circumference, say mineral resources experts.

At least four-fifths of the mass of most SUVs, for instance, is made of "virgin," non-recycled metals that require an extensive amount of digging to extract from the Earth, said researchers who presented their data at the recent meeting of the Geological Society of America.

"(Vehicles) use a lot of resources, both in terms of oil and stuff we dig out of the ground," said mineral resources professor Doug Pride of Ohio State University. "The (resource) cost of driving any vehicle should be required reading by any driver. We should put this in terms that everyone can understand."

To do so, Pride and a group of resource experts sat down and started working out the numbers, car by car and metal by metal.

Take a typical mid-sized family sedan like a 1995 Ford Taurus, Chevrolet Lumina or Dodge Intrepid. They each contain more than a ton of iron metals and more than 300 pounds of non-iron metals like aluminum, researchers said.

Some metals, like iron and aluminum, come from natural ores with up to 45 percent metal content, and so a lot of metal comes out of each shovelful of ore. Other metals — like copper, silver, chromium, lead, zinc and others — are scarcer in ores and require that a lot more earth is moved to extract similar amounts.

The comparison to Meteor Crater was figured by multiplying the entire production of passenger vehicles in 2003 by the amounts of resources required for the different models. That number was then compared metal by metal to how much ore is required to produce the materials.

The team's conservative estimate is that some 66,556,212 cubic yards of earth was mined to make new vehicles in 2003. That's 81 percent of the volume of Meteor Crater.

On a car-by-car level, that translates into almost seven cubic yards of earth mined to produce a Hummer H2 — a 6,400-pound (three-ton) vehicle. At the other end of the spectrum is the 1,850-pound (just under a ton) Honda Insight hybrid that leaves a "hole in the ground" of just under two cubic yards.

"We tried to be conservative," said Pride of the calculations. "We're not trying to pick on anybody."

Instead, the goal is just to make people aware of how much of a limited resource goes into their vehicles — from U.S. and foreign mineral sources, Pride said.

One way to reduce the size of that gaping hole is to recycle more materials from cars, something Canada has already done, said Brendan Bell, energy spokesperson for the Sierra Club.

"We're wasting materials that are already out on the road," Bell said.

Currently only 15 to 20 percent of the parts on some U.S. vehicles are made of recycled materials, Pride said.

The presentation is also a good reminder of something people often forget: that mining is a hugely important part of our current economy, explains mineral resource expert John Memmi, who works for the Republican caucus at the Pennsylvannia Senate.

"I believe it's an issue that if people sit back and think … I don’t think they go that next step and think 'That comes from a mine,'" Memmi said.

This sort of presentation helps people take that step, he said.