Sometimes it is hard to believe certain rock formations are natural… and this is definitely the case with a place in Tasmania called the Tessellated Pavement. It is named this due to the tessellated (i.e. tiled-like) appearance of the rocks along the water. This little tourist spot is near Eaglehawk Neck, on the way to the famous Tasman Peninsula, and only about an hour drive from Hobart. Not only is the Tessellated Pavement a spectacular sight (and photographer’s dream), but it also is a unique geological phenomenon…
Cracks and salt (how it formed)
The rock that comprises the Tessellated Pavement is mostly siltstone that formed in the Permian (about 300 million years ago), by sediments that accumulated on a relatively low-lying area. The sediments eventually got compacted and lithified to form the solid siltstone. Local stresses at the Earth’s surface then caused the siltstone to crack and fracture in certain directions, this is called jointing. There are three mains sets of joints; ENE, NNW, and NNE. The fact that they are mutually cross-cutting without off-set each other is a key observation that tells you the joints formed at the same time. The way they criss-cross each other is what creates the tiled-like appearance.
But wait, the story doesn’t end there… time and water also played (and continue to play) a role in creating this site.
The rocks are currently on an intertidal seaward platform, and thus years and years of erosion (i.e. since sea levels stabilised in the area ~6000 year ago), has exaggerated the tessellation appearance (Leaman, 2001). The constant action of the salt water splashing over and partly covering the rocks with changing tides has lead to the accumulation and percolation salt water on the rocks, particularly within the joint. As the water gets evaporated by the sun, salt crystals forms and as they grow they exert pressure on the rocks causing rocks and joints to flake away and be more susceptible to erosion.
The salt crystallization mostly occurs in the joints, however, water that pools on the top of the rocks furthest away from the ocean dries the fastest and salt crystallization is more intense on the rock surface there, causing the depressed, or “pan-like” tiles.
The opposite occurs for rocks closer to the water, and therefore only the joint really are visibly depressed, creating the “loaf-like” tiles (Banks et al., 1986; Leeman, 2001).
Final thoughts
The Tessellated Pavement is a stunning sight that sparks curiosity of visitors… the reason I checked it out is that actually a friend of mine asked me what it was, as it looked man-made to her! Jointing in rocks is not an uncommon thing, but the special circumstances with salt crystal formations and increased erosion really enhanced this pattern. I would highly recommend stopping by this neat place on the way to the Tasman Peninsula, I hope it sparks your curiosity about rocks as well!
-Stephanie
Thanks for reading! Please subscribe for more posts via email, and/or leave a comment, share this post, or follow me on Twitter (@stephsykora) or Instagram (@stephaniesykora)
[…] Apparently, “The rock that comprises the Tessellated Pavement is mostly siltstone that formed in the Permian (about 300 million years ago), by sediments that accumulated on a relatively low-lying area. The sediments eventually got compacted and lithified to form the solid siltstone. Local stresses at the Earth’s surface then caused the siltstone to crack and fracture in certain directions; this is called jointing. There are three main sets of joints: east-northeast, north-northwest and north-northwest. The fact that they are mutually cross-cutting without off-setting each other is a key observation that tells you the joints formed at the same time. The way they crisscross each other is what creates the tiled-like appearance.” […]
Helped alot in my assignments when I was in need of help in bibliography, thank you for making this!
Thanks for this wonderful site. It really helped with my assignment
Thank you very much 🙂
Thanks for the pics with the explanations. The part about the pans & loaves is really interesting 🙂
You’re welcome, I’m glad you found it interesting and thanks for stopping by my blog. Cheers, Stephanie.
Hello,
my friend & myself very much wanted to see the tessellated pavement in Tasmania.
would you give us some guidance how to travel there from Travellodge Hobart, or any recommendation on Day Tour from Hobart
Hi Stella. Yes, visiting the Tessellated Pavement it pretty easy to do from Hobart. If you rent a car it is only an hour drive south towards Port Arthur. The site is near Eaglehawk Neck. I am not sure if there are any guided tours leaving from Hobart, but likely there are. I suspect there are some that stop here on the way to Port Arthur. Cheers! Stephanie.
[…] Much of this trail segment is lined with boardwalk, making it a very easy walk between beaches. The first bit of it, up from Putty Beach, has some cool-looking rock to ogle and a patch of tessellated pavement. […]
This was really interesting. Thanks for sharing.
Thanks for reading! 🙂
Really awesome. I learn a lot of interesting informations on each new post 🙂 And continue to follow your blog.
I wish you success on your work.
Greetings from Turkey.
Thanks a lot! I’m glad you enjoy my blog and continue to follow along 🙂 Greetings from Tasmania, Australia!
Very cool. It reminds me of the Bimini Road. From what I know of the Bimini Road’s formation, it began in some similar fashion to this Tessellated Pavement, as part of the shore line, and was gradually submerged and experienced further development underwater.
Hmm, I’ve actually never heard of Bimini Road until just now, but I had a look and it does visually look a bit similar. From my brief reading, it sounds like Bimini Road is a sedimentary rock that had cracks further enhanced by erosion before it was fully submerged underwater. So I guess some similar processes with erosion on the shoreline by the ocean.
I love this part of Tasmania, Hopefully I’ll be back down this way over the weekend and get to visit the Tessellated Pavement once again. 🙂
Yes it is one of my favorite spots in Tassie as well, that and the southwest wilderness. Hopefully you can get a chance to swing by the Tessellated Pavement soon, now armed with a bit more knowledge on why it looks like that and how it formed!
I always enjoy your blogs. This one on tessellated pavement is quite unusual!
Bob (USGS geologist/retired)
Hi Bob, that’s very kind of you, I’m glad you enjoy my blog and thanks for commenting. The Tessellated Pavement is quite an odd looking site indeed… I see you worked with the USGS, I always thought it would be great experience, especially with field mapping, to work for one of the government surveys at some point. I hope you enjoyed your time with them. Cheers!
This is awesome, I cannot wait to watch the video!
Thanks Billy 🙂 And yes, the video will be out soon!