ITALIAN TRAVERTINE IN DOWNTOWN EDMONTON
If you travel to Rome, you will undoubtedly want to visit many famous sights that have earthcaches associated with them- the Spanish Steps, the Trevi Fountain, St. Peter's Square, the Fontana dei Quattro Fiumi in the Piazza Navona. What they each have in common is travertine rock. Even the train station has a travertine earthcache. If you are an earthcacher in Rome, you will learn more about travertine rock than you've ever thought possible. This earthcache will save you a 14 hour flight and a bunch of money- you are essentially seeing the same thing here, after all. Right?
Travertine is a type of limestone (a calcium-rich rock composed primarily of the CaCO3 minerals calcite and aragonite) which forms by chemical precipitation from certain types of shallow or surface waters, such as springs and rivers. The trigger for the precipitation is usually gain or loss of carbon dioxide (CO2), which causes a pH change and changes the solution chemistry so that CaCO3 precipitates. This gain or loss of CO2 usually happens very close to the Earth’s surface as the CO2 is lost to or gained from the atmosphere. The waters that produce travertines are usually very acidic (low pH) or very alkaline (high pH). Often, travertines precipitate from acidic hotsprings; as these areas are often lush with vegetation, finding impressions of plants in travertine is common. As a type of limestone, travertine is particularly succeptible to chemical weathering- such as weathering by acid or salt. Testing has found that, despite the many holes that can be found in travertine, it is not porous- likely because the holes are not interconnected. This helps travertine resist weathering from water alone.
Most travertine, including the travertine at the posted coordinates, comes from Italy. In Italy, well-known travertine quarries exist in Tivoli and Guidonia Montecelio, where the most important quarries since Ancient Roman times can be found. The Guidonia quarry has major historic value, as it was one of the quarries where Bernini selected material from which to build the Colonnade of St. Peter's Square. (colonnato di Piazza S. Pietro) in 1656–1667. Michelangelo also used travertine as the material for the external ribs of the dome of St. Peter's Basilica. Travertine derives its name from the former town, known as Tibur in ancient Roman times. The ancient name for the stone was lapis tiburtinus, meaning tibur stone, which was gradually corrupted to travertino (travertine).
The travertine at this location can be found at the former Paramount Theatre of Edmonton. The facade is constructed of black marble, Tyndall Stone, and Italian Travertine. The Paramount Theatre opened in 1952, but has not been used as a theatre since 2003. From 2007-2014, it was used as a church building. It is now listed on the National Trust for Canada's "Top 10 Endangered Places List". In other words, come check out this earthcache and fine Italian stone while you can.
To log this earthcache you will need to answer the following questions, and post a photo:
(1) Look at the photos of any of the Italian landmarks listed as "travertine" earthcaches above. This will allow you to identify what travertine looks like. Based on this information, describe where on the the Paramount Theatre you can find travertine stone? (answer should be more specific than "on the front")
(2) Do you think that the travertine on the front of the Paramount is succeptible to weathering? Why or why not?
(3) From the writeup above, you will note that the various holes in the travertine rock are not internally connected. Look at the holes in the travertine. How large are these holes? Are they uniform sized on each stone or do they vary?
(4) Take a photograph of you, your GPS, or a trackable, in front of the Paramount Theatre with travertine in the background. Italian themed photographs get extra bonus kudos! In light of the June 2019 revised earthcache guidelines, this is a mandatory component of this earthcache. Logs without a photo may be deleted.
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This earthcache has been placed for CARW2020
1. This CARW2020 cache will be published about 6pm on Thursday, February 20, 2020.
2. This earthcache has been placed for the CARW event with the intention that it not be located prior to 9:00 a.m. Saturday February 22, 2020. The caches for the CARW event are released early so that the geocaching community has an opportunity to plan their routes and strategies prior to the event start.
3. Should you hunt and find this cache before the event start, it will not count for the event, and FTF points are only valid as of 9AM February 22nd.
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Sources:
Acidic Weathering of Carbonate Building Stones: https://scholarcommons.usf.edu/cgi/viewcontent.cgi?article=1043&context=geologia
Travertine, Wikipedia: https://en.wikipedia.org/wiki/Travertine
Paramount Theatre, Edmonton: https://archive.nationaltrustcanada.ca/issues-campaigns/top-ten-endangered/explore-past-listings/alberta/paramount-theatre
Earthcache Pages for caches GC71Q8V, GC7Q0XC, GC71RGF, GC6PMXC
Now that you've seen travertine, you can skip this....
