Red Rocks / McGahey Brook (Cape Chignecto - Advocate Harbour)


I've been catching up on a lot of past trips I made in the Maritimes that I didn't have time to post on my blog. One such trip was a rockhunting trek in Nova Scotia in the Advocate Harbour area, West of Parrsboro.

Site (circled in red), Isle Haute (bottom left)

The topography of the southern Chignecto region is very faulted, showcasing the collision of this part of the continent with North Africa some 400 million years ago, forming the ancient Supercontinent Pangaea. The Carboniferous strata of this regions has been folded and faulted in spectacular fashion, neighboring Jurassic (Early) age basalts from North Mountain, which you can see at Cape d'Or and other locations along the Minas Basin, and rhyolites in the West (ie. Spicer's Cove). Cape d'Or is especially known for its natural copper deposits, once mined in the early 1900s.

1- Actual Location (C-H Carboniferous, Early - Horton Group)
CC - Carboniferous, Late - Cumberland Group (ie. Joggins)
2- Cape d'Or, Copper deposits, basalt lava flows, major fault
3- Jurassic, Early - North Mountain basalts (various overlapping lava flows)

Isle Haute, composed mainly of basalt (Jurassic)

Since the last ice age about 11,000 years ago, the area was uplifted. The land rebounded, leaving raised beaches on top of the cliffs with layers of glacial till.


Because the region was involved in this tectonic tug of war, whatever fossils found in the rock has been worked mostly beyond recognition. There are some rare fossils that escaped this calamity, but they are very scarce indeed. Sandstone and other types of sedimentary rock had been metamorphosed, pulled apart and pressed, warped, and molded.

Beading, sandstone under tectonic stress

Tremendous pressure applied to these rocks introduced minerals such as quartz (quartzite). The shales and mudstone are practically pulverized, ground into a very fine material, resulting in this dark sand all over this beach.



Glacial striation or fault scarring?

Horsetail (related to ancient club mosses, lycopsids)

Nice folding!

Folding and faulting

Sedimentary strata changed under incredible stress






Morphology drastically being modified in several episodes


This area is very fascinating and exciting. Here is a place where you can witness the continent being pushed around and shaped over and over during a very long period of time, in various ways, due to harsh and extreme forces exerted by the tectonic activity at the time of continental push and separation over 400 million years. The scale of it is amazing on the grandiose scale to the micro level of change. This shows that rocks can be very malleable under great stress. What doesn't bend, eventually breaks.

Cheers!
Location: Advocate Harbour, NS B0M, Canada

Comments

Post a Comment

Most Popular Posts

Martin Head (Southern New Brunswick)

Image
There's a place, called Martin Head, located just West of Fundy Park that people having been going to for a very long time. I've been talking to people and every time I mention camping sites, people would ask me: "Have you gone to Martin Head yet?". As it turned out I hadn't, so thus became an item that went up in my 'To do' list. Martin Head is a mash up of very old and not as old rocks. The 'island' which goes by the name Martin Head is made up mostly of Cambrian rocks, or even older. The basalts are mixed with some sedimentary rocks of about the same age, and some mineral deposits (I couldn't find which type of minerals occurred). The section between the island and the beach which includes some sections of the cliffs are of younger age, dating close to the Late Triassic. Click here for information about the fossilized Sand Dunes of Martin Head. These are mostly buff or reddish sandstones. There is a small section that juts out fr
Read more

Amethyst Cove (Blomidon, Nova Scotia)

Image
This past Summer I talked to people about collecting local minerals to add to my collection, and several people mentionned Amethyst Cove. Amethyst Cove is a section of Blomidon Provincial Park, near Canning, Nova Scotia. This location is quite difficult to get at as the options to get there are slim. You can access Amethyst Cove either by boat (preferably from Parrsboro at high tide), by walking around Cape Split or from White Water (which could take half a day or more, making it quite fucking impossible), or by repelling down a cliff 300 to 400 feet high, by shaky ropes. I talked to Matt about going to Amethyst Cove someday and didn't think that I would have made it this year. Matt offered to take me there. He was very familiar with the area as he has gone there several time. We picked September 24th to go down. I left Moncton at around 6:30AM and made my way to Halifax to pick up Matt and his buddy Chris. From there we proceeded to drive North towards Wolfville on the 101. (1
Read more

Rock Hunting in Halifax (Nova Scotia, Canada)

Image
Me and my buddy Matt went for a trip to Halifax, Nova Scotia this past Saturday (November 26th, 2011) to snoop around the city and try to collect rocks and minerals. Why snoop around a big city for minerals? Halifax lies on top of a granitic pluton, a mass of magma located under the surface which has slowly cooled. The batholith intrusion was exposed over a long period of time, over several million years. The granite that you see on most road cuts leading in and out of the city was part of that feature. With igneous rock comes the chance to find interesting crystals. The area is known for its quartz (smoky), feldspar (K-feldspar), tourmaline, pyrite (fool's gold), and gold among other things. When we arrived in Halifax, we had driven by some road cuts that had yielded several minerals. We parked the car close-by so that we could go take a look before going for a bite to eat. We took some of our gear and headed out to check the outcrops. The granite contained fine to bigg
Read more