NATR - Rock Spring EarthCache

The Natchez Trace Parkway is a 444-mile drive through exceptional scenery and 10,000 years of North American history. Used by American Indians, "Kaintucks," settlers, and future presidents, the Old Trace played an important role in American history. Today, visitors can enjoy not only a scenic drive but also hiking, biking, horseback riding, and camping. For more information about the Natchez Trace Parkway visit:
Website: www.nps.gov/natr
Facebook: www.facebook.com/NatchezTraceParkwayNPS
Phone: 1-800-305-7417.

The posted coordinates will take you to the parking area and trailhead of Rock Spring on the beautiful Natchez Trace Parkway in extreme northwest Alabama. I hope you learn about the area and enjoy your hike at this wonderful place.

Rock Spring is a very tranquil area with some beautiful scenery. This EarthCache will require you to take the short walk on a nature trail that makes a circle, taking you back to where you began. When you take this walk, you will come upon signs along the way that will tell you about the spring and what the spring creates for this area. Be sure to read the signs and take in what nature has to offer us.

Springs may be formed in any sort of rock. Small ones are found in many places. Larger springs in this area are formed in limestone and dolomite. Both dolomite and limestone fracture relatively easily. When weak carbonic acid (formed by rainwater percolating through organic matter in the soil) enters these fractures it dissolves bedrock. When it reaches a horizontal crack or a layer of non-dissolving rock such as sandstone or shale, it begins to cut sideways, forming an underground stream. As the process continues, the water hollows out more rock, eventually admitting an airspace, at which point the spring stream can be considered a cave. This process is supposed to take tens to hundreds of thousands of years to complete.

Dolomitic limestone is a type of rock that includes up to 50% dolomite. Normal limestone is primarily made up of calcite and aragonite, but dolomite forms in the stone when the calcium ions in the calcite part are replaced by magnesium ions — this process is called dolomitization. This type of rock was once referred to as magnesian limestone in the United States Geological Survey publications, but is now known as dolostone, dolomite rock, dolomite limestone, or dolomitic limestone. Dolomite is a mineral that contains large amounts of calcium and magnesium, which makes it a good fertilizer for nutrient deficient soil.

To get credit for the find simply answer the following five questions and send them to me in a message:

Question #1: Name one of the two types of rock where springs in this area are formed.

Question #2: Can the water from the spring be seen coming out of the ground into the pond? If so, where is it located?

Question #3: Dolomite largely contains what two elements?

Question #4: The United States Geological Survey once referred Dolomite as what?

Question #5: Describe the rock that makes up the stream bed that comes from the pond.

Once you have sent the answers of the five questions in a message, please post a photograph of yourself with the Rock Spring behind you. The photograph is NOT required.

A spring is usually the result of layered rocks where surface water has infiltrated the Earth's surface, becoming part of the area groundwater. The groundwater then travels through cracks and openings ranging from inter-granular spaces to large caves. The water eventually emerges from below the surface, in the form of a spring.

While on this trail around the spring and surrounding area, you will see signs of different types of wildlife. The spring, and stream that it creates, attracts an abundant variety of animals for food and water alike. Dams are created by a variety of sources: animal activity such as beaver: fallen trees and other accumulated plant matter: or a build-up of stream sediment after a heavy rain. Whatever the source, damming obstructs the current enough to allow deep pools to form which support plants and attract insects. In turn, these insects attract other aquatic organisms and their predators.

The slow moving water that is produced by the stream drops sediment it has carried, creating a perfect home for burrowing worms and mussels. Along the quiet edges of the stream, plants gain a foothold in the mud. These plants offer a place for algae to grow, which in turn provides food for tadpoles, turtles and fish. With the sun and water in ample supply, plants fill all available space. Fallen plants and dead animals decay and quickly recycle back into the community, encouraging more growth.

As you emerge from the forest to the opening of the stream side, hear the bubbling of the water. Think about where the water comes from and how it affects every living thing around it. Think about the changes water can bring to an area, the many forms it takes, and how it results in habitats supporting different animals and plants. Reflect on the diverse and changing areas you visited along this trail and how imported change is to a healthy environment.

Water accumulates in underground reservoirs called aquifers. Occasionally an aquifer will touch the surface and the water will flow out in the form of a spring. Rock Spring flows year-round and creates the slow-moving water environment you see pictured below.