My Dad recently asked me to show him more pictures of rocks. Anyone who knows me knows that I never have a shortage of rock photos, something exploited in a drinking game we made up in undergrad. But my Dad's earnest request was well timed. I was just about to go off on another of my geological jaunts across Newfoundland. This one was in the form of the MUN SEG Student Chapter Spring fieldtrip. The MUN SEG Student Chapter is a sub-society of the Society of Econominc Geologists, and is run by the students, myself included, here at MUN. The Chapter had been dead in the water for the last couple years, something my colleagues and I saw as a great shame, what with all the fabulous economic geology research that is done here at Memorial. So we revamped and got it up and going again. This year we've had a trip to the Bell Island Iron Mines, a Bowling Night with AAPG, and numerous exciting guest speakers. But we had bigger plans. And that's how this trip came about.
The gang down the Bell Island Iron Mine in October 2013.
The weather you would expect going to Bell Island in October.
The majority of the (hard rock) people that live on the 5th floor of the Murray Building are economic geologists, specifically ones that work on VMS (volcanigenic massive sulphide) deposits. These are volcanic hydrothermal systems near the sea floor (akin to black smokers) that form big deposits of metal sulphides (metals like copper, lead zinc, sometimes gold). I've been taught the basics behind how they work in class. I've been to seminars from all my colleagues who dissect the individual bits of the system, from the magmatic heat sources, to the muds on top of them, to the deposit itself. Yet I've never actually seen one "in the wild" as I like to call it. And that's why I was so excited about the trip. Add to that the fact that it was my colleagues that were running it, showing us the rocks they have dedicated so much time to, and that we were going further west than I had ever been on this island, I knew it was going to be a good weekend. We started the trip by heading 6 hours west to the Duck Pond Mine, via an overnight stop in Grand Falls-Windsor. After a detailed intro to the rocks we got ready to go underground. This required a number of sexy accessories including white overalls, helmets, headlamps, emergency oxygen packs, safety glasses and hi-vis jackets. I've been underground before in coal and salt mines, but we went down via elevator shaft. It is a completely different experience driving down the ramp in complete darkness, 300m into the earth, with the hustle and bustle of other trucks and machinery around you.
Having a look at the rocks underground.
The gang dolled up after we returned to surface.
Safely back at the surface, laden with tonnes of shiny sulphide-bearing rocks we had lunch and then proceeded to look at drill core from the Boundary and Lemarchant mines, as well as looking at the "scrap" pile, in hope of discovering some goodies.
Found some Au (albeit in core)! It helps when its circled for you through...
Some replacement style VMS textures.
Big diggers.
We then went up to the Baie Verte Peninsula and the Dorset Museum that was to be our home for the next 2 nights. We arrived in the settlement of Fler de Lys to a spectacular sight of broken up sea ice with the most incredible dusky lighting. Me and Eddie were raring to go with our cameras set before the vans had even stopped. My photos don't do it justice.
I upped the saturation a lot but I don't even care.
Why wouldn't you kayak through the ice?
Lovely sunset.
The only Soapstone (talc-schist) outcrop in North America that preserves Paleoeskimo (~1600 yrs ago) vessels being carved out of the rocks.
Next day and we were off the to Ming deposit where again we looked at core and got to pick up shiny samples from the ore pad. We also got to go to the milling facility where those very same metalliferous rocks are concentrated into a product that is shipped off elsewhere in the world for further refinement. This is done by the froth flotation method, by which ore is crushed and then mixed into a slurry. Then the slurry is foamed up to create a froth on the top which holds the metals you're concentrating, which leaves the gangue material you don't want at the bottom. You then skim off the metals from the top using paddles. Watching it in action is surprisingly mesmerising, looking like a bubbling golden cauldron of heavy metals.
A rock like this...
Gets turned into a moving slurry like this...
That gets swept off like this.
As well as the mine site visits we wanted to explore why these mines were there; what geologically allowed these deposits to form. I'm not going to try and explain that to you here, primarily because I'm not even sure myself what was going on. Cool rocks are cool rocks regardless as to whether I can wrap my little brain around a hugely complicated tectonic story. Along the way we stopped at Tilt Cove to see some of the ophiolite sequence, rare seafloor rocks that have been thrust up to the earth's surface. We stopped at Coachman's Cove to see some highly deformed and folded rocks that record crashing together of landmasses. And we saw the locally famed "virginite outcrop", an awesome, striking green rock that went through some strange geochemical processes producing some really odd chromium-rich minerals. Then we finished up at a fabulous roadside outcrop that showing a great number of complexly intruding molten rocks of all different size, colour and composition. All parts of the puzzle that people much smarter than me are trying to put together.
Leftover core pile. Population of Tilt Cove in 1901 = 1370. Population of Tilt Cove in 2011 = 5.
Brecciated pillow basalt at Tilt Cove.
The gang at Coachman's Cove.
Deformed wavy rocks and sea ice.
Another triumph for Miniature Mode.
Green colour in the virginite coming from fuchsite, a chromium-rich mica.
At least 4 phases of intrusion seen in this particular part of the Paul's Lake Dyke Swarm.
My fellow SEG committe members worked their socks off to put on this trip and I and everyone else are very thankful for that. I'm chuffed I finally got to see a VMS in the wild. A lot of golden shiny sulphide samples were taken. A lot of card games were played. A lot of miles were driven. And a lot was learned. Let's hope that the MUN SEG Student Chapter can keep going from strength the strength.
PS. Dad, was that enough rock photos for you?
PPS. If it wasn't, check out the video I put together to commemorate the trip;
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