Harrison´ s cave

Harrison´s cave and park is located in the central uplands of the island in the parish of St. Thomas, a famous tourist location. It is situated at 214m above the sea level. Tourists are taken in an electric powered `tram`along an underground roadway that follows the former course of underground streams. These caves were mapped in 1974 by Ole Sorensen, an engineer and cave adventurer from Denmark, who was assisted by Barbadians Tony Mason and Allison Thornhill. The government of Barbados opened these caves to the public in 1981.
The entrance to the cave is through the Boyce Tunnel, named in honour of equipment operator Noel Boyce, the first member of the construction team to break through the bedrock and into the natural passageways of Harrison’s Cave.

Harrison’s Cave is named for Thomas Harrison, who owned much of the land in the area in the early 1700s. In 1733, Harrison established a school that is today’s Harrison College. It’s not clear whether Mr. Harrison ever entered the cave that bears his name — but others certainly did.

There are a series of caves that were developed within the Upper Coral Rock and are only about 1km south of the edge of the Scotland District ad close to the highest point of the island, Mount Hillaby. The thickness of the crystalized limestone in this area varies between 52 and 56m. A variety of speleothems like stalactites, stalacmites and flowstones beautify these caves. The cave has flowing streams, falls and water pools of various sizes. Harrison´s cave is an active stream cave system at least 2,3km long. Its largest cavern called the "Great Hall" is 15m high. The interior temperature is an average 27 degrees Celsius. The stalagmites in the cave are growing by less than the thickness of a piece of paper each year — but that’s very fast in geological terms!

What is an active stream cave??
Corrasional or erosional caves are those that form entirely by erosion by flowing streams carrying rocks and other sediments. These can form in any type of rock, including hard rocks such as granite. Generally there must be some zone of weakness to guide the water, such as a fault or joint. A subtype of the erosional cave is the wind or aeolian cave, carved by wind-born sediments. Many caves formed initially by solutional processes often undergo a subsequent phase of erosional or vadose enlargement where active streams or rivers pass through them.

To log this earthcache, send me the answers to the following tasks:

1.Look at the biggest stalacmite you see in the cave. What do you think how long it took to grow 10cm? And how long it took, to became that size??

2. When you look at the "river" inside the cave, how much is the flow rate? Do you think the flow rate of the river is related to the size of the cave? Explain!

3. Optional: It would be great, if you can take a photo at GZ and upload it, but it is only optional!