Engulfed in mountains, West Virginians get a science lesson daily. All around us looms 300 million years of geology. It's clear evidence of the mammoth crumpling of Earth's crust, before the era of dinosaurs, followed by long eons of erosion.

Each time you drive through a highway cut or look upward at a soaring cliff or downward into a deep mountain gorge, you glimpse part of the planet's history. Trying to grasp the immense time periods that produced these spectacles can be overwhelming.

Sometimes it surprises me to realize that green mountains aren't as organic as they appear. They're simply colossal rocks, covered by an extremely thin skin of dirt and trees. In fact, mountains are harder rock that didn't wash away, while softer formations around them slowly eroded, leaving valleys.

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James Haught

The opposite side of the Sideling Hill cut displays large upturned strata, dwarfing the four-lane highway below.

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The marvel stemmed from plate tectonics, once called "continental drift." Gargantuan granite and basalt segments of Earth's crust actually float on denser, pliable rock in the planet's mantle. The plates move ceaselessly, perhaps 2 to 4 inches a year, too slowly for humans to notice. Most scientists think the plate movement is impelled by heat currents in the plastic underlayer, and by gravity's downward pull on mile-high new lava ridges in mid-ocean. A few think Earth's rotation and the moon's pull are factors.

A good geology book, "Landprints," gives this account of the Appalachians:

The North American plate once was flat. More than 400 million years ago, eroding sand and pebbles bonded into immense layers of sedimentary rock near shorelines. Seashell debris mixed in to create sections of limestone. (When you enter a limestone cavern today, you're inside an ancient seabed.)

About 250 million years ago, tectonic movement gradually jammed the eastern edge of North America into western Africa and Europe as plates merged into a monster landmass called Pangea. The slow-moving collision had such force that plate edges ruptured and buckled. Who can grasp such a titanic notion as America's entire eastern border crumpling?

"It is hard to imagine deformation on so huge a scale," the book says. "Some folds were pushed completely over on their sides so that older layers lay over younger ones. The result was a mighty mountain range, largely built of sea-floor slabs. ... Sheets of sedimentary rock on the Appalachian Plateau were shoved farther and farther west, some of them almost as far as the Ohio River."

Each time you drive through a highway cut or look upward at a soaring cliff or downward into a deep mountain gorge, you glimpse part of the planet's history. Trying to grasp the immense time periods that produced these spectacles can be overwhelming.

Sometimes it surprises me to realize that green mountains aren't as organic as they appear. They're simply colossal rocks, covered by an extremely thin skin of dirt and trees. In fact, mountains are harder rock that didn't wash away, while softer formations around them slowly eroded, leaving valleys.

Originally, gravity caused rock strata to be formed flat, layer upon layer, during vast eras. But some Appalachian rock isn't flat. It twists upward at bizarre angles along exposed roadsides. When I see mountain layers tipped upright, I'm boggled by the incredible pressure that caused such a marvel.

The marvel stemmed from plate tectonics, once called "continental drift." Gargantuan granite and basalt segments of Earth's crust actually float on denser, pliable rock in the planet's mantle. The plates move ceaselessly, perhaps 2 to 4 inches a year, too slowly for humans to notice. Most scientists think the plate movement is impelled by heat currents in the plastic underlayer, and by gravity's downward pull on mile-high new lava ridges in mid-ocean. A few think Earth's rotation and the moon's pull are factors.

A good geology book, "Landprints," gives this account of the Appalachians:

The North American plate once was flat. More than 400 million years ago, eroding sand and pebbles bonded into immense layers of sedimentary rock near shorelines. Seashell debris mixed in to create sections of limestone. (When you enter a limestone cavern today, you're inside an ancient seabed.)

About 250 million years ago, tectonic movement gradually jammed the eastern edge of North America into western Africa and Europe as plates merged into a monster landmass called Pangea. The slow-moving collision had such force that plate edges ruptured and buckled. Who can grasp such a titanic notion as America's entire eastern border crumpling?

"It is hard to imagine deformation on so huge a scale," the book says. "Some folds were pushed completely over on their sides so that older layers lay over younger ones. The result was a mighty mountain range, largely built of sea-floor slabs. ... Sheets of sedimentary rock on the Appalachian Plateau were shoved farther and farther west, some of them almost as far as the Ohio River."

Originally, the Appalachians were perhaps 8 miles high, taller than the Himalayas, but eons of erosion wore them down to a mile or so.

After the mountain-building phase, mantle currents impelled plates of the Western Hemisphere away from Africa and Europe - and lava upwelled through a fault-line between them, creating the ever-spreading floor of the Atlantic Ocean. Inch by inch, century by century, eon by eon, the spread became 3,000 miles of seabed. Today, lava still rises in the mid-Atlantic as North America creeps westward at about the pace of hair or fingernail growth. Along the West Coast, according to the U.S. Geological Survey, the North American plate wedges atop the rotating Pacific plate. Over the past 170 million years, the USGS says, this collision created the continent's western mountains, presumably buckling the Rockies far inland.

It's awesome to contemplate something so vast as North America relentlessly moving and reshaping the planet, too imperceptibly to notice.

But part of the tale can be seen in many Appalachian hillsides. Creation of interstate highways and Appalachian Corridors required excavations that turned mountains into geology displays. Every schoolchild can see rock layers that took millions of lifetimes to form, then more millions of lifetimes to twist out of shape.

West Virginia has many such displays, but the grandest in this region is just across the state line in western Maryland about five miles northwest of Berkeley Springs. It's the Sideling Hill cut on I-68.

Slicing through the mountain exposed a U-shaped rock fold called a syncline. The 340-foot-high spectacle is so intriguing that visitor centers were built on both sides of the freeway to let travelers gaze at the natural wonder.

Amid today's endless distractions of politics, warfare and other hassles of daily life, it's good for people to stop and ponder a reality that grew a quarter-billion years before humans evolved.

Haught, the Gazette's editor, is author of "Science in a Nanosecond" for youthful readers. He can be reached by phone at 348-5199 or e-mail at hau...@wvgazette.com">hau...@wvgazette.com. Maryland geologist James Reger helped assure accuracy of this article.