In chapter two of 'Your inner fish', Shubin talks about the removal process of of fossils. Using research from the internet/books, explain in detail the multiple ways one can take out fossils and clean them efficiently without damaging the fossils. Do you believe these are the best ways to get a fossil out? Why or why not? Would you recommend the use of explosives on hard rock?
Nikhil Pereira
nikhil.pereira3@gmail.com
The general procedure for fossil removal is very straight forward. The first step in the process is to remove the overburden, which is any substance that covers the top of the fossil. This process can be as simple as dusting the fossil off and can be as complex as using dynamite to blowup a part of a mountain. It all depends on the size and position of the fossil. The next step is to isolate the fossil itself. This is done by carefully excavating around the edges of the fossil so the fossil is isolated on a pedestal of rock, or whatever substance it is in. Next, isolated fossil is covered in wet paper towels, and then plaster-coated burlap strips are applied to the paper towels. The paper towels prevent the plaster from adhering to the fossil, which can potentially damage the fossil. The plaster dries into a hard shell that acts as a jack to protect the fossil. Then the substances underneath the fossil are carefully dug through so the fossil can be removed from its initial burial. A lot of substance is left on the fossil, but it will be later removed by preparators, skilled fossil cleaners. The fossil is then removed and rolled onto the previously-plastered side. The exposed half of the fossil is then covered the same way the other half was so the entire fossil is encased in a large shell of plaster that protects it on its trip to a lab for further study (Museum of the Rockies.org)
ReplyDeleteI believe the methods of fossil removal Shubin described are the best ways to get fossils out of hard rock. One of the main purposes Shubin was looking for a fossil was so he could find tangible, concrete evidence that there was, in fact, a link between the transition of animals from water to land. How would a bunch of broken-up pieces of bone be able to undoubtedly support Shubin’s theory that he found an animal that has never been discovered before?
Using explosives can be good and bad. If a significant amount of rock is needed to be removed in order to, then I think explosives should be used in a very careful manner, making sure the fossil isn’t harmed during the explosion. This is a very efficient and easy way to remove layers of hard rock that would take a lot of work to remove using manual tools like jack hammers and shovels. Explosives obviously shouldn’t be used to remove hard rock if there is very little rock to remove in the first place. Explosives can be rather unpredictable in terms of how the blast will affect the surrounding walls of rock. One miscalculation can ruin a paleontologist’s expedition.
Mikey Ling (mikeyling@ymail.com)
Mikey described the two extremes of digging up fossils. The option to use explosives is very risky and the dust off technique can be time consuming. The following method I researched includes a few extra details and variation from the two methods listed above.
ReplyDeleteAfter the site has been analyzed, bulldozers rather than explosives are used to move large chunks or rock and soil. Paleontologists then use shovels, drills, hammers, and chisels to get the fossils out of the ground. The scientists dig up the fossil and the rock around it in one big lump. They must be careful not to break the fossil as they dig. While digging up the bones the scientists constantly take pictures as it will help them study the history of the fossil in the laboratory. What is unique to this method is that the bones that stick out of the rock are sprayed or painted with a special glue that helps make the fossil strong. This allows the paleontologists to remove the fossil without it breaking easily. After the bone is extracted, as Mikey described, the fossil is wrapped in bandanges and placed in crates with soft padding. These crates help protect the fossils from breaking.
Although explosives may seem extreme, many fossils are located in hard rock that can span up to 40ftx10ft and 6ft deep. The explosives are not extremely strong as they are only used to crack the rock so it can be removed easily. "It's not standard and it's not usual, but it's not experimental," says Dan Chure when referring to the explosive technique, Dinosaur's staff paleontologist. " Dan Chure uncovered many fossils of sauropod using this technique in the Rocky Mountains. Overall, explosives do not need to be used because the fossil is in softer rock than in the Rockies and it doesn't span large areas. Although Mikey said that explosives can be unpredictable, the current technology is so advanced that the paleontologists don't have much to worry about. I bet that in the near future we will be searching for fossils in areas where it's hard to use the dust off method and the old means for using tootbrushes will be outdated.
Eryk Fundakowski- arthur2446@comcast.net
http://www2.scholastic.com/browse/article.jsp?id=4744
http://www.nationalparkstraveler.com/2009/05/fire-hole-dynamite-used-uncover-fossils-dinosaur-national-monument