Welcome to Pubnico Point!
Have you ever gone out geocaching and noticed some of the different rock formations around you? I was out recently in the Pubnico area and noticed some different rock outcrops that I haven’t seen very often. Curiosity got the best of me and I did some research.
Pubnico is a small French Acadian community located in Yarmouth County, Nova Scotia on Nova Scotia Trunk 3. It was founded in 1653 by Philippe Mius d’Entremont. While you are in the area, I encourage you to visit the Acadian museum and the Historical Acadian Village and sample a traditional Acadian dish-rappie pie.
This Earthcache is situated on Pubnico Point, Nova Scotia. The view of the Wind Farm on Pubnico Point and Lobster Bay on a nice day is spectacular. While you are there, the new trail system is a pleasant walk with plenty of benches to rest and enjoy the sounds of the sea birds.
The Pubnico Point Wind Farm, a 30.6 Megawatt farm is the 3rd biggest wind energy producer of the Canadian provinces. Each of the 17 Windmills weighs over 600 tonnes. Each of the Windmills is named after the people associated with the project; fourteen are female, three are male. The first one was named Annabelle.
The Geology
Your walk will take you to an outcrop that is a metamorphosed mudstone that has created the growth of a mineral called andalusite. At this location, the crystals are very uniform in shape and size. What makes this site special is that it is really rare to see such a high concentration of this mineral. If you chip a sample of this mineral, you will notice that is has a slightly pink hue.
Metamorphic rocks have been changed (metamorphosed) by extremes of heat and pressure. Under pressure, original features in these rocks are often deformed or partially destroyed. At this outcrop, you can see other minerals in the rock as well. White quartz and feldspar are a couple of examples.
What is Andalusite?
Andalusite is a rock-forming mineral that is mined for use in high-temperature refractories. Gem-quality specimens are cut into faceted gems and cabochons. Andalusite is a group of minerals made of aluminum and silica. They are also a type of silicates.
Andalusite forms during the regional metamorphism of shale. It is found in schist and gneiss at some present and ancient convergent plate boundaries where the rocks have been exposed to the temperatures and pressures needed for its formation.
Physical Properties and Uses of Andalusite
Andalusite has a number of useful physical properties. It has the ability to withstand high temperatures without alteration. For that reason it is used to make high-temperature ceramics and refractories. The white porcelain of many spark plugs is made using andalusite.
Andalusite is one of a small number of minerals that commonly forms prismatic crystals with a square cross-section. This can be important information to help identification.
Andalusite is a common metamorphic mineral which forms under low pressure and low to high temperatures.
Requirements
To successfully accomplish the requirements for this Earthcache, please answer the following questions. If you enjoy this Earthcache, I would appreciate a favourite point.
Pictures are always welcome but they are optional. There is no need to contact me for confirmation before logging this cache but the information should be sent in, either via email or the message system on geocaching.com, in a timely manner. Should there be any difficulty, I will contact you.
1) Find the Andalusite outcrop and using a compass determine the cardinal direction from tip to tip. Does the outcrop run west to east, north to south, south to north, etc?
2) How long is the outcrop at the posted coordinates? I used my GPS to determine the length, but if it is wet, do the measurement from the shoreline. Please do not venture out to the tip, as it can be extremely slippery.
3) What is the width of the largest part of the outcrop?
4) What mineralogy do you find which you on top of the outcrop?
5) In general, what is the average length of the crystal bumps and describe their shape.
6) Post of picture of yourself or your GPS device. (Optional)
--------------------------------------------------------------------------------------------
Information for this Earthcache has been found using the following reference materials:
Martha Hickman Hild, "Geology of Nova Scotia, Touring through time at 48 scenic sites". Royal Boulder Publications, section 28, p. 152-153. ISBN 8-1 978-1-927099-43-8
Arthur B. Busbey III, Robert R. Coenraads, David Roots, Paul Willis, “The Nature Company Guides Rocks & Fossils” Time-Life Books, p. 53, Pages 68-69. ISBN 3 1111 05192 4668
Frederick H. Pough “A Field Guide to Rocks and Minerals” Houghton Miffln Company Boston 4th edition, plate 45, Pages 289-290. ISBN 3 1111 05016 5123
--------------------------------------------------------------------------------------------