GEOL 102 Lecture Notes - Lecture 13: Thought Experiment, Sulfur, Abiogenesis
Document Summary
By the late hadean and early archean, earth had. Oceans which were nearing modern levels of salinity. Boundary between the hadean and the archean- 3. 8 bya. Earliest undisputed fossils are from 3. 5 bya. The first organisms would have been prokaryotes. Prokaryotes are organisms whose genetic material is not contained in a cell nucleus. Difficult to differentiate groups in the fossil record. Some of the oldest definitive body fossils have been found in south africa and date to 3. 5 bya. Isotopically light carbon is produced by photosynthetic organisms and methane producing members of archaea. Abiogenesis- the chemical processes by which life arises from abiotic sources. Many scientists have attempted to replicate the chemical origins of life in laboratories. We will covering some of the most important experiments and theories. Remember, hypotheses can never be proven only disproven. Experiments are designed to falsify the hypotheses they test. Based on their concept of the early atmosphere.
