Almost 30 million years ago, in what is now northern New Mexico, two of our planet's ever-shifting plates, the North American and the Pacific, crunched up against one another, causing a dramatic separation in the earth's crust through which in time a great river would flow.

Today that separation in the earth's crust remains spectacular, and we know it as the Rio Grande Gorge, named for the river that runs through it, sometimes ferociously, sometimes serenely.

To drive through that canyon is to drive through one of this continent's beautiful and breathtaking wonders, and last week President Obama used the powers vested in him by the Antiquities Act of 1906 to make it the "Rio Grande del Norte National Monument."

Corks were popping and hands were clapping from Taos to 1600 Pennsylvania Ave. as the President signed a proclamation adding some 240,000 acres of northern New Mexico, all the way up to Ute Mountain near the Colorado border, to the roster of national monuments.

It was an especially poignant moment for New Mexico's recently retired U.S. Sen. Jeff Bingaman, who was present for the White House signing ceremony. Bingaman has long championed national park or monument status for the area.

"This is a great day for New Mexico," the former senator said.

Bingaman knows whereof he speaks. National monuments not only offer environmental and cultural protections for the areas they embrace, they have also been known to prove economically beneficial for surrounding communities.

According to the nonprofit independent research group Headwater Economics, after 1987 when President Reagan established the El Malpais National Monument in Cibola County, population in the nearby area increased by 15 percent, jobs grew by a whopping 98 percent, and per capita income shot up by 67 percent.

Some 12 years later, after President Clinton set aside fully 1.7 million acres in southern Utah to create the Grand Staircase-Escalante National Monument, the economic impact in the region was much the same, not only in population and job growth but in real personal income, which increased by 40 percent.

It happened again in 2000 when Clinton designated a swath of southwestern Colorado for the Canyon of the Ancients National Monument, with job growth hiking up by 10 percent and personal income increasing more than 15 percent.

Suffice it to say, civic and business leaders in economically hard-pressed Taos and Rio Arriba counties, where the Rio Grande del Norte is located, are hoping for a similar boost from the president's designation of the new national monument.

Chances are they won't be disappointed. By all reckonings, national monuments become significant tourist destinations, and with increased tourism comes sorely needed entrepreneurial and employment opportunities.

But in this reporter's opinion, it will be (as long has been the case) the visitors who will benefit most from their Rio Grande del Norte experience.

The geology, alone, is arresting and it expands the mind.

Most of us, when we enter a canyon or gorge and look down to the river running below, ponder the eons it took those running waters to slowly erode away dirt and rocks until at last it carved the course that would take it to some lake or sea or ocean.

But visitors to Rio Grande del North witness nothing so patient.

Theirs is the opportunity to imagineor try to imagine--what the violent earth must have been like almost 30 million years ago as it ground relentlessly upon itself, belching up billions of tons of lava and rock, lifted itself upward some 5,000 feet and wrenched its parts in two until it left behind this pathway through which a river now flows.

It is a wonder.

Hal Rhodes is the founder of New Mexico News Services and a longtime TV journalist on the public television station KNME in Albuquerque.