| A | B |
|---|
| What did James Hutton do? | Father of Uniformitarinism |
| Uniformitarianism | Idea that forces shaping earth, change earth slowly |
| Catastrophism | Idea that geologic change occurs suddenly |
| What did Charles Lydell do? | combined Uniformitarianism and Catastrophism |
| Modern Geology | A "happy medium" between uniformitarianism and catastrophism |
| Explain the meaning behind "Happy Medium" | Earth is changed by gradual forces, and occasionally catastrophic forces |
| What is Palentology? | study of past life |
| What do Paleobotanists study? | study of past plant life |
| What is Relative Dating? | Determining whether an object of event is older or younger than other objects or events |
| Describe the Principle of Superposition. | Younger rocks lie above older rocks in undisturbed sequences |
| Examples of Disturbing Forces | Folding, Faulting, Tilting, Intrusion, Weathering and Erosion |
| What is an unconformity? | a surface that represents a missing part of the geologic column, representing a time not recorded in the rock |
| Two ways unconformities can form. | Nondeposition and Erosion |
| What is a disconformity? | A missing layer of horizontal sedimentary rock |
| What is a nonconformity? | A missing layer of igneous or meta rock |
| What is an angular unconformity | A missing layer of rock in rock layers that have been tilted or folded |
| What is absolute dating? | The process of establishing the age of an object by determining the number of years it has existed |
| Isotopes | Atoms of an elements that have a different number of neutrons than the regular element. |
| Radioactive decay | When unstable isotopes break down into stable atoms |
| Radiometric dating | determining the age of a sample by looking at the ration of parent to daughter isotopes |
| Parent isotope | the unstable isotope that wants to become stable |
| Daughter isotope | the stable isotope that is produced when the parent isotopes decays |
| half life | the time it takes one half of a radioactive sample to decay |
| Carbon 14 Dating | method of radiometric dating used on samples that were or are made of material that was once living |
| K-Ar, U-Pb, Rb-Sr | Methods of radiometric dating |
| Fossil | remains or physical evidence of an organism preserved by geologic processes |
| Petrifaction | the process in which minerals replace an organisms tissues |
| Trace fossil | Any naturally preserved evidence of animal activity |
| mold | a mark or cavity made in sedimentary rock by a shell or other body part |
| cast | a type of fossil that forms when sediments fill in the cavity, or mold left by a decomposed organism |
| Index fossils | fossils of organisms that lived during a relatively short period, well defined period of time, used to date rocks and other fossils |
| Eon | the largest division of geologic time |
| Era | a unit of geologic time that includes two or more periods |
| period | a unit of geologic time into which eras are divided |
| epoch | a subdivision of a geologic period |
| extinction | the death of every member of a species |
| Geologic Time Scale | The standard method used to divide the Earth's long natural history into manageable parts |
| Cenozoic Era | Age of Mammals |
| Mesozoic Era | Age of Reptiles |
| Paleozoic Era | Age of Fish |
