EARTH 7 Lecture Notes - Lecture 2: Permineralization, Absolute Dating, Lithification
Document Summary
He spent a lot of class talking about his trip to madagascar. There, he discovered the jaw of a massive crocodile-like amphibian. South america used to be an island before 3 million years ago when a small land bridge formed. It was genetically isolated for a while, allowing for the formation of many diverse mammals. Places where infrastructure is not great, or just where humans haven"t been, you"re likely to find many new fossils and even new species. It depends on where fossils are likely to form, and more importantly how they form. Sedimentary (the rocks where fossils are most likely to form. ) They form from sediments (rock debris like cobble, sand, mud). Rocks that form directly from melted earth which eventually cools down to become solid) Metamorphic (when sedimentary of igneous is squeezed and/or pressurized causes a change to chemical structure) With igneous rocks, we can determine their absolute ages, but they only rarely preserve fossils.
