Ridgeley Sandstone facts for kids

The Ridgeley Sandstone is a type of rock found in the Appalachian Mountains of the United States. It is mostly a sandstone, which is rock made from tiny grains of sand, or sometimes a quartzite, which is a very hard rock made mostly of quartz. This rock formed during the Devonian Period, a very long time ago.

You can find the Ridgeley Sandstone in states like Pennsylvania, Maryland, West Virginia, and Virginia. This rock is usually fine-grained, meaning its particles are very small. It's also siliceous, which means it's rich in silica, a common mineral. Sometimes, its lower layers are calcareous, meaning they contain calcium. You might even find fossils in it, or small pebbles.

The Ridgeley Sandstone can be anywhere from 12 to 500 feet (4 to 150 meters) thick. Over time, it slowly wears away into white quartz sand. This sand can then be carried away by wind or water. However, sometimes it builds up in large piles where the rock sticks out of the ground. When you break a fresh piece of Ridgeley Sandstone, it looks white. But if you see it outside, it often has yellowish stains from iron oxides, which are like rust.

A wide view of a road cut through the Ridgeley Sandstone near Shirleysburg, Pennsylvania.

Where Does Ridgeley Sandstone Get Its Name?

The Ridgeley Sandstone was first described and named in 1913. It got its name from a place called Ridgeley, West Virginia. This town is located across the North Branch of the Potomac River from Cumberland, Maryland.

The exact spot where it was first studied, called the type locality, was set at the town of Ridgeley in Mineral County, West Virginia. For a while, there was some confusion about whether the Ridgeley Sandstone was the same as other sandstones, like the Oriskany Sandstone from New York or the Monterey Sandstone from Virginia.

Later, in 1940, a geologist named Butts helped clear things up. He explained that the Ridgeley Sandstone was indeed the same as the Oriskany Sandstone and the Monterey Sandstone. Because of the rules for naming rock layers, the name Oriskany Sandstone was officially chosen for these rocks.

Where Can You See Ridgeley Sandstone?

The Ridgeley Sandstone is very strong and doesn't wear away easily. This means it often forms tall ridges and hills in the Ridge and Valley area. You can easily spot these rock formations from south-central Pennsylvania, through western Maryland and eastern West Virginia, all the way to Craig County in western Virginia.

For example, the Ridgeley Sandstone helps form parts of famous mountains like North Fork Mountain, New Creek Mountain, and Wills Mountain. These mountains are part of a large geological fold called the Wills Mountain Anticline. However, it's important to know that the very top of the main ridge of this structure is usually capped by an even harder rock called the Tuscarora Quartzite, which is older.

Other cool places where you can see the Ridgeley Sandstone sticking out include Caudy's Castle (also known as Castle Rock) and Ice Mountain. Both of these interesting spots are in Hampshire County, West Virginia.

Special Uses of Ridgeley Sandstone

At Berkeley Springs, West Virginia, warm water naturally flows out of the ground from mineral springs located in the Ridgeley Sandstone. These springs are found along a ridge called Warm Springs Ridge. People have used these warm waters for spas and relaxation for a very long time. Today, these spa facilities are part of Berkeley Springs State Park.

Sometimes, the Ridgeley Sandstone is also dug up, or quarried, and then crushed into sand. This special quartz sand is used to make glass. There is one such quarry near Berkeley Springs that uses the Ridgeley Sandstone for this purpose.