A rhythmic spring (also: ebb and flow spring, periodic spring, intermittent spring) is a cold water
spring from which the flow of water either varies or starts and stops entirely, over a fairly regular time-scale of minutes or hours. Compared to continuously-flowing springs, rhythmic springs are uncommon, with the number worldwide estimated in 1991 to be around one hundred.
Theory
Although the cause of the periodicity in flow is not known for certain, the most accepted theory (first postulated in the early 18th century) is that as groundwater flows continuously into a cavern, it fills a narrow tube that leads upwards from near the base of the cavern, then downwards to the spring. As the water level reaches the high point of the tube, it creates a siphon effect, sucking water out of the chamber. Eventually air rushes into the tube and breaks the siphon, stopping the flow if there is no other source feeding the spring, or reducing the flow if there is a continuous flow from another non-siphon source.
In 2006 the
University of Utah studied the
Intermittent Spring
A rhythmic spring (also: ebb and flow spring, periodic spring, intermittent spring) is a cold water spring from which the flow of water either varies or starts and stops entirely, over a fairly regular time-scale of minutes or hours. Compared to ...
in
Swift Creek canyon
A canyon (from ; archaic British English spelling: ''cañon''), or gorge, is a deep cleft between escarpments or cliffs resulting from weathering and the erosion, erosive activity of a river over geologic time scales. Rivers have a natural tenden ...
in
Star Valley
Star Valley is located in the United States between the Salt River Range in western Wyoming and the Webster Range of eastern Idaho. The altitude of the valley ranges from to . Three major Wyoming rivers, the Salt River, the Greys River and th ...
,
Wyoming, United States. Kip Solomon, a
hydrologist at the University concluded that "The spring water's gas content has now been tested
.. The data strongly suggests the water was exposed to air underground; strong support for the siphon theory."
Notable rhythmic springs
The Intermittent Spring in Wyoming, mentioned above, is the largest rhythmic spring in the world.
The
Gihon Spring in the
City of David in
Jerusalem used to be a rhythmic spring before modern-time overpumping affected the level of the underground water table. It was of great historical, archaeological, and cultural importance because it is what made possible the human settlement in
ancient Jerusalem.
Pliny the Younger – who is famous for his accurate description of the Vesuvius eruption of AD 79 – also accurately described a rhythmic spring in the last letter of Book IV.
Pliny the Younger
Gaius Plinius Caecilius Secundus, born Gaius Caecilius or Gaius Caecilius Cilo (61 – c. 113), better known as Pliny the Younger (), was a lawyer, author, and magistrate of Ancient Rome. Pliny's uncle, Pliny the Elder, helped raise and educate ...
, ''Letters''
4.30
/ref> This rhythmic spring is still acting to the same time scale today (Villa Pliniana
Villa Pliniana is a villa originally built in 1573, on the site of a more modest pre-existing building, in the territory of the municipality of Torno, in the province of Como, on the right bank of the western branch of Lake Como.
Fonte Plinia ...
spring in Como, Italy).
References
*
*
*
*Ognjen Bonacci & Davor Bojanić
Rhythmic Karst Springs
Hydrological Sciences Journal, Feb 1991
External links
Zaganjalka spring
{{DEFAULTSORT:Rhythmic Spring
Springs (hydrology)