Blue Spring EarthCache
-
Difficulty:
-
-
Terrain:
-
Size: 
(not chosen)
Related Web Page
Please note Use of geocaching.com services is subject to the terms and conditions
in our disclaimer.
This cache requires a short hike from the parking area.
Two of America’s clearest and most beautiful spring-fed rivers make up the Ozark National Scenic Riverways, the first national park area to protect a wild river system. The Current and Jacks Fork Rivers wind through a landscape of rugged hills and towering bluffs.
Springs are places where water flows out of the ground under its own volition, either as a result of gravity or hydrostatic pressure (hydrostatic head.) Occasionally well drillers will hit a layer of ground water which then flows out without being pumped--this is known as an artesian well.
Springs may be of either fresh water or mineralized water, in which case the spring is then termed a mineral or salt spring. These mineralized waters were early recognized as having great economic value by settlers as sources of salt and other medicinal minerals.
In general, springs can be categorized by their geographic setting. Some springs are seeps, in which the water flows out of sand, soil or gravel with no discernable outlet. Seeps are common along impermeable layers of shale, or porous rocks which hold much water such as through sand, or sandstones. The highly fractured limestone and dolomites of the Ozarks also support seep springs. Much spring water enters Ozark rivers directly from the water table via seeps in the river bottom, which are detectable by the coolness of those areas underfoot, and increases in river flow, with no creeks or surface drainage apparent.
The most common type of Ozark spring is the gravity flow onto the surface of underground streams or conduits, typified by a cave stream. These spring supply passages emerge at ground level, as in a cave with the cave stream exiting at the cave entrance; or above ground level, often along a layer of impermeable rock, creating a waterfall. Depending on the size of the passage and whether or not the passage is partly air-filled, these may be enterable by divers or cavers.
Sometimes completely water-filled underground streams are quite a distance below the surface, and drain relatively large tracts of land. In these cases, the water actually flows "uphill" at an angle of 20 to 45 degrees, coming out under pressure, often through a narrow area called an orifice, or from beneath an underwater bluff. These sorts of springs are of great interest to hydrologists, because they help them learn how groundwater moves in a karst area. Most of Missouri's well-known large springs are of this type.
Blue Spring is located approximately 12 miles east of Eminence on Highway 106. It is one of the deepest springs in the area with a depth of over 300 feet. The spring flows relatively slowly from a very deep cave shaft that is situated at the base of a dolomite bluff. It is deep blue in color because spring water is actively dissolving away limestone as it moves through the earth. This dissolved limestone, along with the influence of the spring's depth and the blue of the sky, impart the blue color. Rainy conditions wash silt into the water and may make springs appear milky or cloudy, or even brown.
Logging Requirement:
To log this cache please post a picture of both you AND your GPSr with the spring in the background, and send me a message via this site with the answers to the following two questions.
a. Visit the upper observation deck, how many pieces of wood that make up the platform you are standing on?
b. What is the current average flow of the spring?
Log your post, stating where you are from and maybe a little about your day of geocaching in this area.
I am aware that cameras break and batteries run out—if this happens, send me an e-mail message via this site and I will not delete your post.
Please visit the Missouri Department of Conservation website (visit link)
***Permission granted by the Missouri Department of Conservation.***
Additional Hints
(No hints available.)