Rock City Educational Resource Guide
Follow the links below for a specific portion of the Geology section.
Underlined words defined in Geology Vocabulary
Lookout Mountain is a landform with amazing geological phenomena. The top of Lookout Mountain is where you will find Rock City Gardens. Rock City Gardens is an amazing journey through time. The massive rocks of the garden tell the story of Lookout Mountain that many people do not know.
The beaches became something different. Ocean waves and currents deposited sand on the beaches. Over time the sand was compressed to form sandstone. Sandstone is a sedimentary rock that is made of tiny
At the same time the sandstone of Rock City was forming, Lookout Mountain itself was being born. Tectonic movements of the earth’s plates caused a series of powerful earthquakes. The plates pushing against each other buckled, pushing rock upwards to form what is called a folded mountain. You know these folded mountains as the Appalachian Mountain chain. The limestone of the sea formed the heart of Lookout Mountain and the sandstone beaches are at the top.
The sandstone atop Lookout Mountain has undergone erosion. Erosion is the process through which rocks are broken down and carried away. Water, wind, plants, or ice can do this. Water can break down a rock as it flows over it or as waves wash upon the rocks. As the water passes the rocks, it carries it away bit by bit. Wind erosion is more common in dry areas like deserts. Wind blows dust and sand at rocks and the abrasive actions sculpt the rocks into amazing shapes. Plants can erode rocks as their roots work their way down into the cracks of the rocks breaking them apart. Ice is a very powerful force of erosion. Glaciers gouge out valleys and can completely remove a hill as they travel through an area. Ice can form in saturated pore spaces and crack the rocks. The rocks at Rock City have most likely been eroded by water that was flowing through the area millions of years ago. Also the roots of the plants on the trail are contributing to this erosion. A great example of an eroded rock at Rock City is the Mushroom Rock. Looking at Mushroom Rock you can see the layers in the rock that characterizes it as a sedimentary rock made of
Crystals and Coral
at Rock City Gardens
Walking through Fairyland Caverns you will see crystals across the ceiling. The crystals you will see are not natural to the area but were brought in. Crystals are solids that form in a regular repeated pattern and have the same arrangement of particles over and over throughout the entire structure.
You will also see rocks that seem to glitter. These silvery rocks are made up
Underlined words defined in Geology Vocabulary
Sedimentary rocks are formed when sediments are deposited in layers, or
strata. These layers are pressed down until the particles become cemented together. Sandstone rock is a type of sedimentary rock and contains the
mineral quartz. Rock City Gardens has boulders and rocks made of sandstone rock. Sedimentary rocks like sandstone form layers that are visible and may contain fossils. While at Rock City you can examine the different sediments of quartz that formed the sandstone.
Metamorphic rocks are formed from sedimentary, igneous, or other metamorphic rocks. The rocks are formed by changes in pressure or changes in temperature.
The rock cycle is a continuous
process that changes old rocks into new rocks. The chart
shows how the cycle works.
Environmental Education: Soil Erosion
Not all erosion happens the way it should. Soil erosion is a natural process
where soil is moved by wind or water. In recent years, accelerated soil
erosion has become a problem. Deforestation is a major cause of soil erosion. Trees have deep roots that hold the soil in place. When the trees are
removed, the soil is loosened and can easily be washed away. Extensive
farming also causes soil erosion. Land that has been farmed too much is
easily eroded away and loses nutrients. After land has been farmed too
much, even if it is not eroded away, it is no longer able to sustain plant life.
Building homes and roads also damages soil. During construction the land is left bare to rain and wind, making it easier to become eroded.
Soil erosion (and degradation) can leave devastating effects. Excessive rain
in areas that have been eroded can result in landslides or mudslides.
Farmers lose land that is used for producing food. Silt and mud can be washed down streams and build up downstream causing problems for people in
that area. Silt and mud can be washed into the ocean where it settles on the
bottom. Organisms that live in the ocean are killed by the change in their
Landform A feature on the earth’s crust. Examples of landforms aremountains, valleys, plains, and plateaus.
Metamorphic Rock Rock formed when other types of rock (sedimentary and igneous) are exposed to heat and pressure.
Sedimentary Rock Rock formed from sediments that have been pressed together over time to make solid rock.
Strata Layers of sediment that are pressed together to make sedimentary rock.