GLGY 209 Lecture Notes - Lecture 12: Calcium Carbonate, Orthorhombic Crystal System, Mollusca
Document Summary
Study of ancient ecosystem involving the reconstruction of the habitat or environment in which organism or communities of organism lived. Polar bears, penguins kingdom in future as fossils for polar climate. Trilobites: marine environment from late cambrian to permian ( 520 ma to 240 ma) Study of the spatial relationship with the development of distinct environment. Study of fossil distribution in space and time. It involves sediment dating and layer correlation based on fossil content. Study of the ancestor-descendant relationship between fossils species and correlation with events in earth"s geologic history. Geologic event correlation with morphology or absence of organism. Processes that lead to the preservation of organism hard parts (bones, shells). Fossilization processes tissues are lost through organic matter decay. Partial or complete change in shell mineralogical composition after death of organism. Mineralogical composition changes, but chemical composition remains the same. Aragonite (orthorhombic caco3) shells in mollusc change to calcite (rhombohedra caco3)