Welcome to my Earthcache! An Earthcache is a special type of geocache where there is no container to find - instead you are looking for a unique geological feature of the area and need to answer questions, as well as posting a picture, in order to claim the find. The goal of this Earthcache is to educate visitors about differences between Speleothem and Calthemite, and assist in the identification of samples located at GZ.
The samples are located near the Pymatuning Spillway near Meadville, PA. The vieweing area for the spillway is wheelchair accessible and is open from 7am until 5pm daily.
EARTHCACHE REQUIREMENTS
As with all of my ECs, I am not looking for PhD thesis level responses, but I am hoping that you take some time to enjoy the area and learn something new. Please include a list of all cachers with your answer, if answering for more than one caching name. There is no need to send individual answers.
To claim a 'find' for this Earthcache you must answer the following questions and send your answers in a message or email to the owner using the link at the top of the page. You can log your find with a photo at GZ. Send your answers to the tasks. I will be in contact if there is a problem, no need to wait for a response as long as the required photo is included in your log.
Observational Task
At GZ, you find a large spillway. Look inside the spillway, and you will find white growths on the inside of the tunnel. You can find more information about these growths in the description below. Theese growths are what you will need to observe in order to answer the questions.
Questions to Answer
1. Read the below description and state, in your own words, the major difference between speleothem and calthemites.
2. Looking inside the tunnel, you will see several sections of growth. Choose one and describe it - is it wet? dry? smooth? shiny? bumpy? slimy? what colour is it? is it made up of many sections, or one large growth?
3. Based on the below description and your observations, what would you classify these as?
4. Mandatory: Include a photograph of yourself, your GPS, a signature item, thumbs up, etc at the spillway. You do not need to show your face in the photo, but your photo must be unique to you.
Please send me the answers using the Geocaching Message Center or send me an email with your answers to the above questions, then go ahead and log this earthcache. You do not need to wait for my response to log. I will contact you if there are any issues with your answers. Feel free to post additional pictures as well, but please do not post your answers with your log.
Strange, Beautiful Structures
Speleothems are mineral formations in limestone caves, such as stalactites, stalagmites, and flowstones. Many unique structures – including stalagmites and stalactites – form inside both man-made and naturally occuring caves as water seeps through the limestone to create carbonic acid, which drips through cave roofs and onto their floors. Structures inside a cave may require millions of years to develop.
Some of the geological structures that may develop inside a cave include:
Speleothem
“Speleothem” is a general geological term for a deposit of calcium carbonate in a cave, including formations such as stalactites, stalagmites and flowstones.
Flowstone
Flowstones are speleothems (deposits of calcium carbonate) on the walls or floor of a cave formed from a gradual flow of water over a relatively broad area.
Stalactite
The term stalactite comes from the Greek work stalaktos, which means “dripping”, because these other-worldly formations “drip” from the roofs of limestone caves. Essentially, water reacts with carbon-dioxide to form carbonic acid. It then seeps slowly through the roof of the cave, depositing calcium carbonate, which hardens and builds up over time to form a stalactite.
Stalagmite
Stalagmites are corresponding formations on the floor of caves to stalactites. Stalagmites rise from the floor in a build-up of calcium carbonate over time, from mineral-bearing water dropped from the roof of the cave. The term stalagmite comes from the Greek word, stalagma, to “drop”.
Column
Sometimes, stalactites and stalagmites meet, forming a pillar or column of rock-hard calcium carbonate.
Helictite
A formation of calcium carbonate in a cave that grows in a twisted, curled fashion, like a helix (hence the name), seemingly defying the laws of gravity.
What is a Calthemite?
Calthemite is a secondary deposit, derived from concrete, lime, mortar or other calcareous material outside the cave environment. Calthemites grow on or under, man-made structures and mimic the shapes and forms of cave speleothems, such as stalactites, stalagmites, flowstone etc.
Calthemite stalactites can form on concrete structures and "artificial caves" lined with concrete (e.g. mines and tunnels) significantly faster than those in limestone, marble or dolomite caves. This is because the majority of calthemites are created by chemical reactions which are different to normal "speleothem" chemistry.
Calthemites are usually the result of hyperalkaline solution seeping through a calcium-rich man-made structure until it comes into contact with the atmosphere on the underside of the structure, where carbon dioxide from the surrounding air facilitates the reactions to deposit calcium carbonate as a secondary deposit.
Calthemites are generally composed of calcium carbonate which is predominantly coloured white, but may be coloured red, orange or yellow due to iron oxide seeping rust along with the calcium-rich deposits. Copper oxide from copper pipes may cause calthemites to be coloured green or blue. Calthemites may also contain minerals such as gypsum.
This EarthCache has been prepared by a proud:
