We were going to see some kin folk in Goodspring, Tennessee and decided to grab a cache along the way.  The cache is near a nice spring coming out of the rock walls.  Gave us the idea to place an earthcache here for everyone's enjoyment.  Couldn't get any history on the town name but I am sure this spring has something to do with it.  Don't confuse it with Goodsprings, Tennessee which is in McMinn County.

The area you are standing is at the edge of the Outer Nashville Basin and the Western Highland Rim ecoregion of Tennessee.  It is a region consisting of higher elevations with Mississipian era limestone and Devonian era shale.  With this diverse karst topography, areas of water collects underground and when the aquifer fills to capacity the extra runoff has to find a way out.  This formation is called a spring.

So, what is a Natural Spring? A spring is a point where groundwater flows out of the ground, and is thus where the aquifer surface meets the ground surface. Springs may be formed in any sort of rock. Small ones are found in many places. In Tennessee, the largest springs are formed in limestone and shale in the karst topography of the central part of the state. Both shale 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.

There are three types of springs; seepage, fracture and tubular springs. The term seep refers to springs with small flow rates in which the source water has filtered through permeable earth.  A fracture spring discharge from faults, joints, or fissures in the earth, in which springs have followed a natural course of voids or weaknesses in the bedrock. A tubular spring flows from underground caverns.

Springs are classified by the volume of water they discharge.  The largest of springs are "first magnitude", that's defined as flowing at a rate of at least 2800 liters or 100 cubic feet (2.8 m³) of water per second, down to 8th magnitude with a flow rate of less than 1 pint a minute.  The following is a chart to explain the classifications of springs.

Obtaining Credit for this Earthcache

To obtain credit for this earthcache please send the following answers to our message or email link.

1.  In your opinion, what type natural spring is this? Explain.

2.  Using the chart above, estimate the magnitude of this spring at the time of your visit.

3.  (OPTIONAL) Please post picture of you and your GPSr at the natural spring.

Plenty of parking on both sides of the road but please be careful.

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