Hey #GeologyMastodon may I get an assist in identifying this rock?! I believe I have hit bedrock about 1 metre down in my #BackyardProject #PoolPond excavation.
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Hey #GeologyMastodon may I get an assist in identifying this rock?! I believe I have hit bedrock about 1 metre down in my #BackyardProject #PoolPond excavation.
It is a light grey to brown but has shiny black surfaces (I thought at first it was a bit of coal!) that can be scraped away with a fingernail. It flakes apart fairly easily but it is quite hard. It's definitely going to be the bottom of my hole!
We are on #VancouverIsland in #PortAlberni
#Geology #Rocks -
martin_fffreplied to Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธ last edited by
@chris pretty sure that's some old refuse or dumped builder's rubble
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Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธreplied to Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธ last edited by
This is what the Google Earth layer from the BC Government โGeological Bedrockโ section says for our area.
I believe the yellow area corresponds to โJurassic to Neogene_sedimentary rocksโ. Third from the bottom in the list.
#GeologyMastodon #BackyardProject #PoolPond #VancouverIsland #PortAlberni #Geology #Rocks
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Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธreplied to martin_fff last edited by
@martin_fff I would be shocked if that's the case!? But maybe?? It seemed pretty darn hard. But it was also under a metre of clay.
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martin_fffreplied to Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธ last edited by
@chris oh, under a metre of clay? what are the chances your back yard has never been disrupted before? No old coal mines pits nearby?
I don't know what it is, but I would havce assumed the blackening was soot
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CatSalad๐๐ฅ (D.Burch) :blobcatrainbow:replied to Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธ last edited by
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Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธreplied to martin_fff last edited by
@martin_fff I believe our house was the first house on this property (built 1940) the middle of the new town so probably the first time it was disturbed? It's reasonably close to the house though.
There were coal mines all over the place around here (though less than the Nanaimo side of the Island).
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Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธreplied to CatSalad๐๐ฅ (D.Burch) :blobcatrainbow: last edited by
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Mat Wrightreplied to Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธ last edited by
our Nanaimo house is 1911, built for the original rail manager (we are right on the line - and it still has the original coal cellar, plus if we dig down into the garden over a meter it's coal residue and stone - we know there is an old shaft underneath so think it's the slag
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Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธreplied to Mat Wright last edited by
@MatWright @martin_fff cool!
ya, I don't think it's coal mine. I've never heard of a mine on this side of town (there is a mine in the hill under Argyle, the hill to the south of us. We're also near the top of the hill. -
Jorge Stolfireplied to Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธ last edited by
Have you hit a continuous layer of that rock? Or just chunks of it embedded in the clay?
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Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธreplied to Jorge Stolfi last edited by
@JorgeStolfi definitely seems like a layer. The hole is 2m wide and I hit it at the same level on both sides of the hole.
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Gib ๐๐๐๐บ๐ฆreplied to Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธ last edited by
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Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธreplied to Gib ๐๐๐๐บ๐ฆ last edited by
@gibbonguru @catsalad lol. SAFETY FIRST
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Jorge Stolfireplied to Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธ last edited by
But is it just solid rock, or a bunch of separate pebbles?
Those samples you showed are smooth with rounded edges. They look like they have been tumbled for some time at the bottom of a river or on a beach.
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Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธreplied to Jorge Stolfi last edited by
@JorgeStolfi Seems like semi solid sedimentary rock. I can only get the excavator bucket teeth into it and scrape layers of it off.. Definitely not pebbles.It crumbles in kind of light grey rubble.
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Mat Wrightreplied to Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธ last edited by
@chris @martin_fff it could still be slag used for foundations, levelling properties
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Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธreplied to Mat Wright last edited by
@MatWright @martin_fff certainly possible!
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Mat Wrightreplied to Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธ last edited by
@chris @martin_fff I've been trying get archive stuff from the Nanaimo museum and city hall, but it's been a slog - so, our property was one of the original farms, given to rail and mine managers, we still have 3 of the original fruit trees
and I do think there is a shaft, probably ventilation, to a mine at the back end of the garden
does VIU have a Nanaimo archive?
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Chris Alemany๐บ๐ฆ๐จ๐ฆ๐ช๐ธreplied to Mat Wright last edited by
@MatWright I believe they do. You could likely call the Library and ask. (I wouldn't recommend doing that next week though... a little crazy the first week back!