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Fossil Forms. Types of Fossilization. Amber Petrification Tar Seeps Freezing Natural Mummification. Amber. How does it work?. Soft resin is secreted from a tree. The resin hardens and the organic molecules begin to cross-link and polymerize.
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Types of Fossilization • Amber • Petrification • Tar Seeps • Freezing • Natural Mummification
How does it work? • Soft resin is secreted from a tree. • The resin hardens and the organic molecules begin to cross-link and polymerize. • The hardened resin is called copal which is known as a subfossil. • The copal continues to polymerize and lose volatiles through evaporation. • The process takes millions of years and then the hardened resin is called amber. • Some organisms become trapped in this sticky substance and they are preserved.
Under what conditions does it occur? • Molecular polymerization is a process that needs heat and pressure to be completed. • The whole process may take millions of years.
Where are specimens of this type commonly found? • Most of the trees produce resin for protection against diseases and infections, so amber can be found in many parts of the world, however, it’s commonly found in the Baltic region. • The Baltic region has the suitable circumstances for the formation of amber. • Exposure to sunlight, rain and extreme temperatures lead to the break-down of resin before it hardens.
What types of organisms are commonly preserved in this way? • Insects • Plants • Lizards • Frogs • Crabs • Snails
A 23-million-year old lizard fossil was found preserved in amber! • This is how amber is used to determine the ages of organisms. • Paleontologists use Absolute Dating to determine the age of this fossil and therefore the age of this lizard. • Since this fossil is 23 million years old, Uranium-238 was used to date this specimen. • The soft tissue remains of the lizard have been preserved.
Bibliography • http://en.wikipedia.org/wiki/Amber • http://www.businessinsider.com/a-23-million-year-old-lizard-fossil-was-found-preserved-in-amber-2013-7 • http://www.museumoftheearth.org/planyourvisit.php?page=tempexhibitions/amber/Paleo-processes • http://webecoist.momtastic.com/2011/09/13/windows-on-the-past-7-amazing-creatures-preserved-in-amber/
How does it work? • Trees end up being covered by layers of sediment and buried by sand or ash after they get cut off or die. • Water with a lot of dissolved minerals enters into the wood and deposits minerals inside the tree’s cell. • Over time, all of the cells become filled with minerals while the organic matter decomposes. • The water evaporates and minerals slowly work their way in to wood and fill the cells taking on the exact shape of the old cell and the resulting stone loos exactly the same like the tree.
Under what conditions does it occur? • When trees decompose in certain areas and mineral solution such as groundwater come over. • Mineral solutions should contain petrifying minerals like silica, calcite or pyrite.
Where are specimens of this type commonly found ? • Petrified wood is found on every continent except Antarctica. • Areas with a large number of petrified trees include: Australia, Germany, Brazil, Canada, China, United Kingdom and many other countries
What types of organism are commonly preserved in this way ? • Trees
How does it occur • Subterranean asphalt leaks to the surface • Creates a large area of natural asphalt • Animals fail to escape when they fall in
Under what conditions does it occur • Material reaches the surface • Lighter components vaporize • Leaving only thick asphalt
Specimens are commonly found at • Tar seeps occur anywhere where oil is naturally found
Organisms that are preserved • Mammoths • Bears • Wolves • Cats • Fossils • Elephants • Bacteria
Fossilization: Freezing By: Miral and Heba
Why is this elephant frozen? You will find out in the rest of this presentation.
Freezing Mummification • The low temperatures of frozen soil and ice can protect and preserve organisms. Because most bacteria cannot survive freezing temperatures, organisms that are buried in frozen soil or ice do not decay.
Cold Temperature • The reason that the organisms’ bodies don’t decay is because bacteria and fungus cant survive in the cold temperature. • There is nothing to decay the bodies.
Locations • Alaska and Siberia • Northern latitudes • All frozen fossilslived in cold climates.
Fun Fact: ‘The Maiden’ • This is a 500-year-old frozen Incan girl • Also known as ‘the Maiden’ • Suffering from a bacterial infection when she died • First time a disease has been diagnosed in an ancient body • She was sacrificed on the Argentinian volcano Llullaillaco, 22,100 feet above sea level
Natural Mummification • A process in which an organism is preserved naturally based on the climate or conditions which are usually dry, cold, icy, or swampy places.
How does this occur? • This occurs from the weather condition where there is less bacteria, which means the body will not be able to decompose • There are different types of natural mummies • Extreme coldness • Acid • Salinity • Desiccating dryness
Extreme Coldness • Ötzithe Iceman • Well preserved body but only stomach was missing • Ice Maiden • Buried during a ceremony in a wooden chamber • Llullaillaco child mummies
Acid • Tollund Man • Incredibly preserved body
Salinity • Salt Man • Scientist would know what people ate at that time from their organs
Desiccating Dryness • Tarim mummies • These mummies die due to dryness in this city
Where are specimens of this type commonly found? • These specimens are usually found in: • Deserts • Very cold places like Greenland • Swamps
What types of organisms are commonly preserved in this way? • Stomaches • Bones • Liver • Most of the body
Video • http://www.youtube.com/watch?v=kluH9ahe4aM