Turnpike Bluff facts for kids
Turnpike Bluff (80°44′S 30°4′W / 80.733°S 30.067°W) is a cool rock formation found in Antarctica. It was first mapped in 1957 by a group of explorers called the Commonwealth Trans-Antarctic Expedition. They named it "Turnpike Bluff" because it was like a tricky toll booth or entrance to a very difficult area.
This area was full of deep cracks in the ice, called crevasses, on the Recovery Glacier. The expedition's special vehicles had a really tough time getting through this part on their way from Shackleton Base to the South Pole in 1957. Turnpike Bluff is located about 9 kilometers (5 nautical miles) southwest of Mount Homard, right at the very end of the southwest part of the Shackleton Range.
What is Turnpike Bluff Made Of?
The rocks at Turnpike Bluff are part of something called the Turnpike Bluff Group. These are sedimentary rocks, which means they formed over millions of years from layers of sand, mud, and tiny bits of other rocks. You can see these rocks on the southern side of the Shackleton Range.
The oldest rocks at the bottom are made of clastic materials (broken pieces of other rocks) and a hard rock called quartzite. Above these, there are more clastic rocks that contain carbonate, which is a mineral often found in shells or limestone. These layers even have signs of ancient life called stromatolites, which are like layered mounds made by tiny living things from the Riphean age, a very long time ago!
On top of these layers, there's over 1 kilometer of greywacke and quartzitic arenite. These are types of sandstone, and they are mixed with layers of pelite, which is a fine-grained rock like shale.
These sedimentary rocks sit on top of even older rocks. These older rocks are from the Archean time, which was about 1.4 billion years ago! They are a type of granitoid rock, which forms from cooled magma deep inside the Earth. Over time, about 526 million years ago, these rocks also changed due to heat and pressure in a process called Metamorphism.
