Posted by : Emily | On : September 30, 2015


Decided to visit Economy River Falls yesterday for some exercise, a nice drive, and 750 Ma Geology…



The Canadian Shield is a massive piece of the earths crust that has been geologically stable for at least 1000 million years. However, the margins of this plate have been the location of collisions, faults, and separations (rifts) with adjoining plates, resulting in hills and valleys as well as forming mountains and seas. With the passing of a few tens of million years, mountains would erode and fill in sea basins, resulting in more rocks which could then be deformed and faulted with the further movement of the plates.

The Appalachian (geologic) Province forms a very wide band of rocks immediately southeast of the Canadian Shield and the majority of the eastern seaboard of North America, from Texas all the way to Newfoundland! Geologists are fond of these rocks because they record direct evidence of at least three major plate collisions resulting in three major mountain-forming events (orogenies). This is where the rocks of Economy River Falls come in.

The rocks creating the falls were originally part of a mountain chain that formed a microcontinent in the seas between two plates that rifted apart around 900 million years ago. The plates then reversed their direction, closing the sea, and sandwiched the mountain chain some 730 million years ago. Geologists call the mountain chain Avalonia (after the Avalon peninsula in Newfoundland) and call the collision event the Acadian Orogeny. Today the rocks show deformation characteristic of major crustal convergence (folding, faulting, and stretching) resulting in gneisses and mylonites (pictured below).


The most amazing part of the story is that Avalonia rocks can be found on three continents! The original plates that squashed Avalonia have drifted apart and are now separated by the Atlantic Ocean. They carried pieces of Avalonia with them and can be found in Europe (Great Britain, Germany, and Spain) and in Africa (Morocco).

To learn more about the geology of Nova Scotia (including the Economy River Falls), pick up a copy of Geology of Nova Scotia at your local bookstore!



Posted by : Emily | On : June 2, 2013

Amethyst Cove IMG_3094

A gorgeous day for rock-hounding at Amethyst Cove in Nova Scotia. Steep terrain led us down to a beach covered in basaltic rock littered with mineralized vesicles and agate nodules. Only the tides will limit your exploration – you must be up and down a 3km beach within 3 to 4 hours, before the mighty tides of the Bay of Fundy force you back up the cliff! Our initial visit revealed crystalline amethyst, quartz, natrolite (+/- tomsonite and stilbite) as well as massive magnetite, hematite, chert and agate. The next visit will yield some more-spectacular agate and amethyst…




Click here for more information on the mineralogy of Nova Scotia.



Posted by : Emily | On : May 18, 2013

Cunard's Beach

Had a fantastic day prospecting around Ovens Natural Park near Lunenburg, Nova Scotia. Discoveries in the area spurred on a gold rush in 1861 that yielded approximately 5800 ounces of gold in six months, without the aid of machinery . We didn’t get a chance to do any panning on the beach this time, but found some spectacular arsenopyrite crystals and a great display of the complexity of the Halifax Formation!

NS Arsenopyrite Arsenopyrite crystals



Posted by : Emily | On : March 31, 2013

A visit to Nova Scotia’s South Shore for rocky inspiration: