Australia

Geology Photo of the Week #28

Matt Herod April 2, 2013

Happy April Fools/Easter everyone! I know that I am a day late, but yesterday was a holiday in Canada. Spring is also in the air, not today actually since it is -7 currently, but we have no more snow, and we had a few nice days over the Easter weekend. It is therefore appropriate for the photo of the week to be something eggy.

A piece of Pleistocene emu egg shell. Found near an ancient aboriginal campground in South Australia. (Photo: Matt Herod)

This photo is of a fragment of Pleistocene age emu egg shell that was found in Port Augusta, South Australia.

Bonus Photo: The duck-billed platypus, a monotreme and one only two types of egg laying mammal in the world.

Platypus (Photo: Matt Herod)

Cheers,

Matt

Geology Photo of the Week #17 – Jan 6-12

Matt Herod January 7, 2013

Happy New Year everyone! I hope that you all had relaxing and enjoyable holidays. I sure did. It is time to start off the new year with the 17th edition of the photo of the week. Here in Ottawa it is a balmy -19 degC with the wind chill making it feel like -28 degC right now! Happily I am toasty and warm inside…for now. If you’re curious the coldest place in Canada at the moment is Eureka, Nunavut at -40 degC and a windchill of -46 degC!!!

To overcome the inevitable chill you just got reading that last sentence the photo below is of a more balmy place that we can say with certainty was extremely hot at some point due to its volcanic origin. It is not obvious at first glance, but if you look a little closer you can see that the cliff the falls are pouring over is made of columnar basalt. Columnar basalt forms when a thick lava flow cools. As the flow cools, stresses build, and in order to accommodate these stresses cracks form resulting in columns with a polygonal shape. As you can see Milla Milla falls, which are located near Cairns, Queensland, are pouring over a cross section of a lava flow. By the way, the temperature in Cairns tomorrow is 33 degC!!

Milla Milla falls in the Atherton Tablelands, Queensland, Australia. (Photo: Matt Herod)

Zooming in at the Milla Milla falls to see the columnar basalt. (Photo: Matt Herod)

Thanks for reading and stay tuned for lots of a new posts in upcoming weeks!

Cheers and stay toasty my friends!

Matt

Geology Photo of the Week # 10 – Nov 4-10 – A Mysterious Monster!

Matt Herod November 5, 2012

I apologize for the delay posting this. I was in Washington DC earlier this week to take in a Supreme Court hearing that never actually happened due to Hurricane Sandy. My flight out was also delayed and thus many other things in my life are delayed right now including this post.

This photo poses a bit of a conundrum…since I don’t have a clue what it is! I have an idea, but I’d like to get other opinions as well. I apologize for the poor quality of the photos. I had to climb up a 5m cliff and then take the photo of the overhang above me at full zoom with my little point and shoot. The rock is a reddish sandstone and is the bottom of a rippled bedding plane. You can kind of see the ripples at the right side of the photo. As for scale I don’t have an exact one but it is approximately 10-15cm long and 5cm wide. The location is the southern end of the Flinders Ranges in South Australia, about an hour’s drive north of Port Augusta (see the map below).

So here is your challenge: what do you think that oval-like shape is? It appears to be a fossil of some description, but what is it? I am not ashamed to admit that I don’t know. Please guess in the comments section below.

(Photo:Matt Herod)

Approximately where I was staying just north of Port Augusta on the sheep and cattle station of some friends. The Flinders Ranges are just to the east.

As I said I have a suspicion what this could be although I am not sure. I believe it is an Ediacaran fossil that dates back between 635 and 545 million years ago. Indeed, the Flinders Ranges are home to a little village called Ediacara only a few hundred kilometres north of where I was and the namesake of the Ediacaran.

I suspect that these impressions are possibly of the Ediaracan creature Spriggina or maybe Dickinsonia? It appears to have bilateral symmetry and is reasonably large and ~10 cm long and 5 cm wide.

Spriggina Floundensi (Image: Wikipedia)

The other possibility that I have been considering is Dickinsonia. Dickinsonia is classified as likely an animal of an unknown kingdom. Regardless of its affiliation, or lack thereof, it also has bilateral symmetry and can be quite large. Indeed, the species D. lissa has been found up to 15 cm. It can also have similar morphology to my mysterious fossil as D. lissa can have an elongate shape.

Dickinsonia species and their morphologies. (Image: Wikipedia)

So I leave it to you to figure this out. Please let me hear your opinions since I certainly am no paleo expert, but I’d love to get to the bottom of what this mysterious fossil is.

Thanks for reading,

Matt