Mining Association of Nova Scotia Profile picture
Aug 6, 2020 6 tweets 8 min read Read on X
We love our coasts - especially in this heat! - but don't often think about how they came to be. Here's how #Halifax's #NorthwestArm formed:

#nspoli #cbpoli #novascotia #CapeBreton
@vote4labi @GaryBurrill @bmaguirens @AndyFillmoreHFX @TourismNS Image
Much of peninsular #Halifax’s bedrock is slate. Sediments deposited as deep-sea muds 500 million years ago were compacted into shale 450 million years ago. When North America and North Africa collided 400 million years ago as a result of tectonic plate movement...
#nspoli #cbpoli Image
...the heat and pressure generated by the collision turned the shale into slate. That’s how slate is formed – it’s metamorphosed (transformed) shale.
The #NorthwestArm was formed by glaciers eroding the slate and carving a trough in the bedrock.
#nspoli #cbpoli #novascotia Image
Slate erodes relatively easily because it is layers of sediment. The layers make it easy for water and frost to get in between and break it apart. Mountain building – upward pressure from the continents colliding – also fractured the slate along the Arm.
#nspoli #cbpoli Image
After glaciers removed the fractured rock, the trough filled with water after the last ice age as sea levels rose. (Sea levels are lower during ice ages because so much water is frozen in glaciers).
#nspoli #cbpoli #novascotia #CapeBreton Image
Alternating layers of mud and sediment – the original sediment from 500 million years ago - can be seen in the picture below at #PointPleasantPark's Black Rock Beach.
#nspoli #cbpoli #novascotia #CapeBreton Image

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More from @MiningNS

Feb 25, 2021
@nsgov announced new rebates for electric vehicles yesterday. Mining makes #greentech like electric cars possible because they are mostly made of minerals and metals.
#nspoli @KeithIrvingNS @IainTRankin @NS_Energy_Mines @ns_environment @ChenderMLA @AllanMacMaster @MLAChuckPorter Image
For example, an e-car has 183 pounds of copper wiring in it because copper is used in every major component from the motor to the inverter and the electrical wiring. There is about four times more copper in an e-car than in a car with an internal combustion engine.
There are about 400 electric cars on Nova Scotia roads - a total of over 73,000 pounds of copper!
An electric car uses 25-50 grams of silver, so Nova Scotia’s 400 e-cars contain about 15,000 grams of it.
Read 9 tweets
Sep 23, 2020
The Morris Street Engine House has been declared a municipal heritage property!
#Halifax’s Fire Station #2, as it is also called, was built 1907-08 of reinforced concrete.
Here's the story!
#nspoli @HFXFireHistory @HRMFireNews @hfxfire @HFXFirefighters @hfxgov @MikeSavageHFX
Concrete is a mixture of aggregates and paste. The aggregates are sand and gravel or crushed stone; the paste is water and portland cement. (The terms cement and concrete are often used interchangeably, but cement is actually an ingredient of concrete...
#nspoli
...Cement is the glue that holds concrete together.)
Reinforced concrete means the concrete is poured over a frame, usually steel bars, that give the structure greater strength.
#nspoli
Read 12 tweets
Sep 21, 2020
We love getting questions about mining, minerals and geology! We were asked about sinkholes and whether they are a risk when walking in the woods.
#nspoli #cbpoli #novascotia #capebreton @oxfordsinkhole ImageImage
The short answer is yes, sinkholes are real but no, they are not a major risk and should not prevent you from enjoying outdoor activities.
Most natural sinkholes are caused by groundwater naturally eroding rocks like gypsum, salt and limestone which are water-soluble.
#nspoli Image
The water erodes the rock, leaving an underground cavern. Eventually, the weight of the rock and earth above the cavern causes the sinkhole to form. Sinkholes can form either gradually (i.e. a small depression appears and perhaps grows larger over time) or by sudden collapse. Image
Read 18 tweets
Sep 20, 2020
We love getting questions about mining, minerals and geology! We were asked about the historic #NewCampbellton coal mine in #VictoriaCounty.
#nspoli #cbpoli #novascotia #capebreton #nshistory
@JaimeBattiste ImageImage
The New Campbellton coal mine was opened in 1862 by Charles J. Campbell, a former Member of Parliament, Member of the Legislative Assembly and executive council member. The community had been named Kelly’s Cove but was changed to New Campbellton in 1862 in honour of Mr. Campbell. Image
A sample of New Campbellton’s coal was sent to the 1865 Dublin Exhibition and “was very favorably noticed by the Judges,” according to a report.
#nspoli #cbpoli #novascotia #capebreton #nshistory Image
Read 18 tweets
Sep 19, 2020
Mining built #NovaScotia!
#Halifax was founded in 1749 and its first court house is reported to have been built by 1754 on the northeastern corner of Buckingham + Argyle streets. After the building burned in 1789, the courts were temporarily housed in various buildings.
#nspoli ImageImage
In April 1851 a bill to provide Halifax with a county court house was passed. Mr. H.G. Hill, a prominent #Halifax architect, prepared a plan for a wooden building.
However, since the records of the county, wills, deeds and other papers of public office were...
#nspoli #novascotia Image
...to be stored in the court house, it was important that the building be fire-proof. Also, a number of serious fires in #Halifax in 1857 led to the passage of a bylaw that required large buildings be made of stone or brick, so Hill's plans for a wooden building were abandoned. Image
Read 10 tweets
Sep 18, 2020
The Sullivan Creek #coal mine, before and after!
It's one of several mines reclaimed around #AlderPoint #CapeBreton in the late 1900s/early 2000s - examples of how mining makes temporary use of land and then land can be used other ways.
#nspoli #cbpoli #novascotia @JaimeBattiste ImageImage
The first mine in the area was the Scotia Mine, or #NovaScotia Steel & Coal Company No. 4 Colliery, on Toronto Road, which operated on the Sydney Main (Harbour) Seam from 1915 to 1921.
#nspoli #cbpoli #novascotia @JaimeBattiste ImageImage
Coal quality and structural issues (including water inflow) plague the Harbour Seam west of Florence so upon closure of the colliery, production on the Harbour Seam was limited to the Company’s No. 3 Colliery in Florence, which had opened in 1902...
#nspoli #cbpoli #novascotia ImageImage
Read 19 tweets

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