Tidal Chart: https://www.tide-forecast.com/locations/Pistolet-Bay-Newfoundland/tides/latest
The Hare Bay Allochthon Melange of millennia ago and the Vikings of 1,000 years ago have a lot in common -- both came from the east, made landfall at the tip of the northern arm of Newfoundland, and both left traces for generations far in the future to wonder about.
Logging Requirements:
1. Which primary cardinal direction are the Melange of rocks leaning? This would show you which direction the allochthon was heading.
2. Which of three tree types of deformation did you see the most of at GZ? (See description below)
The Hare Bay allochthon is the dominant geological feature between this point and Pistolet Bay. You will get to examine the rock features as you visit this quiet beach located between the Norsteed Village and L’Anse aux Meadows National Historic Site Parks Canada. In fact, for some it would be walking distance from Norsteed Village, although parking coordinates for a closer approach are provided. Please don’t block entrances or other vehicles in the very tiny parking area at the posted parking coords.
MELANGE: A melange is a mixture of larger rocks (large enough to be mapped) that are mixed into a matrix of smaller rocks or gravel/sand. In reality this means large volcanic or metamorphic rocks that have been incorporated into sedimentary matrix.
How do rocks get into a melange? THere are two methods.
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Easily deformed sediment may squeeze into cracks in adjacent rocks fracturing them and then carrying those pieces along as movement continues
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Fragments of rock fall into soft sediment from above (volcanos for example)
There is no container at this site, since it is an earthcache. Please make observations and send answers to the logging requirements to me via GC Messenger.
The Hare Bay allochthon is the dominant geological feature here. It is a series of thrust slices pushed on the ancient continent of Laurentia from the ancient Iapetus ocean’s floor. “At L’Anse aux Meadows a tectonic melange -- the rock unit along which the Hare Bay allochthon traveled -- occurs along the shore” (Hild, 62) and is easy to access at GZ.
At this site you are looking for easily deformed rocks surrounding more resistant rock fragments. The matrix that surrounds the blocks was once just a muddy sediment. As the Hare Bay allochthon travelled (logging requirement #1 asks for you to identify which direction), over the blocks, the matrix deformed, flowing and squeezing in response to the pressure and movement (Hild, 64).
You should be able to see at least one of the following types of modification. WHich one(s) you see are logging requirement #2. Modification variations are a result of the fluid in the rock while it deformed as well as the strength of the block materials.
A. Fresh looking blocks with clean and straight edges
B. Worn, broken and rounded off blocks
C. Blocks and matrix that have been flattened and stretched.
References:
Hild, Martha Hickman. "Tectonic On Ramp: L'Anse Aux Meadows Melange." Geology of Newfoundland: Touring through Time at 48 Scenic Sites ; Field Guide. Portugal Cove-St. Philip's: Boulder Publ., 2012. N. pag. Print.
"Mélange." Wikipedia. Wikimedia Foundation, 24 June 2012. Web. 17 July 2017.