This was our first visit to the Sculpture Park...and look what we found! The boys loved it - we hope you do, too! As it turns out, this is my 20th EC. Enjoy!
NOTE: GROUP responses will not be accepted; please send as an individual response. This EC is not available at night, or in heavy snow. You will need some height to get the best view of the EC.
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As of January 3, 2021: I've done some additional research and now recognise the following which will be reflected in a title change:
Let us settle something right away. Often what we consider an ‘inukshuk’ is actually called an inunnguaq.
An inunnguaq (ᐃᓄᙳᐊᖅ), meaning “imitation of a person,” is a stone sculpture that is shaped to look like a body or person and has spiritual meaning with practices related to it.
An inukshuk (ᐃᓄᒃᓱᒃ), meaning “that which acts in the capacity of a human,” is more of a general vertical mound of rocks that stand as a directional guide or landmark on a hillside to follow.
After further reflection and some feedback, I've upped the D by a 0.5 point. I hope that doesn't upset anyone unduling.
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This EC will have you examining the geology of the Inuksuk. Please give yourself enough time to answer all questions. General responses (e.g. "it's sedimentary because it has layers") will not be accepted. We don't expect you to be a geologist, but we do expect you to read the lesson, think about what you see, and apply some new learning in your responses.
Please submit complete answers to the given questions as soon as you complete the EC, and preferably through the messaging service rather than sending via email. I will read and reply to all answers submitted. Insufficient/inaccurate/missing answers may result in a deleted log.
Finally, group responses will not be accepted. If in a group, each person must supply their own answers and post their own photos. Thanks!
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The Lesson - Geodes, Nodules and Crystals
Inuksuk means “that which acts in the capacity of a human” in Inuktitut, the language of the Inuit. An inuksuk can be small or large and consists of several rocks balanced on each other. Because it is built from whatever rocks are on hand, each one is unique. (Please note: according to the research I did, both spellings - Inuksuk and Inukshuk - are apparently acceptable. In Inuktitut, the spelling is "inuksuk".).
A geode is a rock formation that combines materials to form a hollowed-out rock lined with crystals. While the crystals in this example mostly are gone, we are able to find a few that remain intact and others that still have remnants. It can take thousands to millions of years for a geode to form. Geodes that are completely filled with crystals (leaving no space or void) are called "nodules".
Geodes initially are formed as a hollow bubble inside a rock layer. They are formed from volcanic rock; as the lava cools and air bubbles appear, they become covered with more volcanic rock and a geode may form. The air bubble must remain hot for a geode to form, and rain (water) events need to happen. Water is absorbed into the rock, and chemicals are released from the rock to the water. The water then passes through the outer, rocky hard layer and becomes trapped in the inside of the bubble. Eventually, crystals form, and the deposition of mineral crystals continues. Crystal size and shape are influenced by how long formation takes place, as well as the water flow through the air bubble.
It should also be noted that geodes can also form in sedimentary rocks, such as limestone, dolomite, and calcareous shale. In these deposits, a gas-filled void can serve as the opening for geode formation. Shells, tree branches, roots and other organic materials often decay away to leave a void for the formation of mineral materials. These cavities can be filled with quartz, opal, agate or carbonate minerals. They are generally smaller than the geodes formed in volcanic rocks.
Crystal colour is determined by the type of rock within which the geode forms, the types of minerals that are trapped and heat. Most geodes have quartz or calcite forming the crystals, because 90% of the Earth's crust is formed of silicates. Minerals such as magnesium (purple - will lead to amethyst formation), iron (red or purple), manganese (pink), titanium (blue) and nickel, chromium and copper (green) are also possible. Silicon dioxide will create a clear/white and/or grey hue.
Questions - group answers will not be accepted, so please send as individual responses.
1. AT GZ: look up at the top of the Inuksuk
a) Looking at the crystals: what colours and minerals are represented here? Provide an approximate % of each mineral.
b) Choose at least 3 distinctive crystals and describe the size and shape. Submit the photos with your responses (do NOT POST the photos).
c) Is what you are looking at a geode? Explain, using geological principles, why or why not.
2. AT GZ: look at the base of the Inuksuk
a) Find a nodule - measure the length and width (in cm) and send a photo with your answers (do NOT POST the photo).
b) What colour is the nodule? What is the likely chemical composition? Refer back to the lesson.
c) Looking at the rock surrounding the nodule and geodes, what type of rock is it and why do you think so? Provide specific evidence from GZ.
3. MANDATORY: To demonstrate that you were on site, take a photo of you/your GPS standing in front of your sculpture (from the nearby sculpture park) of choice. Not the Inuksuk. Please post this with your log.
Thanks for visiting! I look forward to reading and replying to your answers and seeing your photo. NO spoilers (logs/photos), please!