Sasha Says - Shag point Plesiosaur and Coal mining - a podcast by Whitestone Geopark

Today we're gonna be talking about an area down the coast of Otago. It's a place called Shag Point that's not far from Palmerston. So there's a few different things to see down there. So I'd just like to touch on that. First of all I know lots of our listeners out there are really interested in fossils. And down at Shag Point, a number of years ago, there was a plesiosaur fossil pretty much intact that was found in the silt/mudstone down there and it is now on display at the Otago Museum. People can go there and have a look at it. And the reason it's significant is because it was the first mainly intact plesiosaur to be found in New Zealand. So it was an amazing discovery - round about seven meters long and it was discovered and removed by the University of Otago - the Geology Department there. So first of all, there's this Plesiosaur fossil - go and check it out at the Otago Museum. Now, the next thing that's really amazing at this Point, when you are there you can see seals and other wildlife there, which are, you know, incredible all along the coast there. There's incredible wildlife. But we've got a really interesting social story that's attached to Shag Point. And that's when you're walking from the car park, there's little bits of rounded quartz under your feet that kind of roll around. It's not the gravel that was brought in for the road. And when I went there I said to Lisa, "Oh this looks abit like the Taratu Formation" which is a formation that sits on top of the schist basement rock in Otago. And we went round the corner abit and lo and behold, we discover that apparently this area used to be commercially mined for coal. Now there is an old little coal mining wagon there that you can look at in the car park. Now, the Taratu Formation was the first sediment that was deposited on the basement rock. And it's hugely variable in its composition, but it's basically quartz that's been reworked out of the schist and in places you get coal. So the coal tells us that it was terrestrial deposition - that means that it was deposited on the land. So bituminous coal was first discovered here in the 1830s. And in 1862, they realised it was actually commercially viable to mine and it was mined right up into 1972. So it's a pretty recent history, really - long time of mining. And it eventually closed and the shafts, the old coalmine shafts have been flooded. But yeah, it's quite an interesting site. So you've got the plesiosaur and then that was obviously in marine sediments and then you've got this Taratu Formation as well with coal mining. Now, one of the interesting things that I get often asked is if there's a plesiosaur there would have been plesiosaurs swimming around when the limestone was deposited. The answer is no. Okay. So the limestone is around about 25 million years old now this plesiosaur is from sediments around about 70 million years ago. Now the significance with this is around about 65 million years ago. So after the plesiosaur had been swimming around more recent, what you get is called the K-T boundary. And that's a boundary between the Cretaceous time period and the Tertiary time period. World wide it saw a mass extinction of life on earth. Plantlife, animallife, what have you. So the plesiosaur went extinct at that point - it was no longer. And that's when the dinosaurs went extinct as well. A dinosaur is separate from a plesiosaur - a dinosaur is a land animal and plesiosaur swum in the ocean. So it's a really significant discovery in New Zealand to find this plesiosaur in the siltstone. And it's here in East Otago. I just encourage you to get online - I've just written a Facebook post about this and also a podcast about the plesiosaur so get online and have a listen and have a read and we'd just love to hear from people about their experiences out and about in the Geopark.

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