| A | B |
|---|
| Fossils | Remains or evidence of a once living thing |
| sediments | small pieces of rocks (gravel, sand, silt, or clay), shells, and other materials that were broken down over time. |
| sedimentary rock | hardening of layers of sediments |
| metamorphic rock | Sedimentary or Igneous rocks changed by heat, pressure, or chemical reactions |
| igneous rocks | cooling and hardening of magma |
| petrifaction | occurs when minerals replace an organisms tissues |
| mold | empty spaces left when an organism decays |
| cast | Created by molds filled in by sediments which harden |
| imprints | Thin materials like leaves and feathers leave their impression in soft sediment which hardens |
| freezing | Preserved the woolly mammoth |
| tar pits | Preserved bison, camels,giant ground sloths, wolves, vultures & saber-toothed cats |
| amber | Preserves whole insects |
| trace fossils | Marks or evidence of animals tracks, trails, footprints, or burrows |
| amber | Hardened tree sap |
| examples of fossils | bones, shells, pollen grains, seeds, and imprints of an organism |
| Igneous rock | Does not contain fossils |
| Metamorphic rock | Does not contain fossils |
| Sedimentary rock | Contains Fossils |
| What do fossils tell us? | Appearance and activities of extinct organisms |
| What do fossils tell us? | How living organisms have changed over time |
| What do fossils tell us? | Earth's climate has changed |
| What do fossils tell us? | Earth's surface has changed |
| What do fossils tell us? | Many different life forms have existed at different times in Earth's history |
| Preserves entire organism fossils | Asphalt (Tar pits), freezing (Ice), and amber |
| Permineralization | Type of petrifaction in which the pore space in an organism's hard tissue is filled with minerals |
| An example of petrifaction | Petrified wood |
| Erosion | Process of moving sediment from one location to another |
| Forces of Erosion | Running water, wind, glaciers, and gravity |
| Weathering | Break down of rock into fragments |
| Rock Cycle | The continual process by which new rock froms from old rock material |
| Erosion | Exposes fossils that have been preserved in rock |
| Fault | Break or crack along which rocks move |
| Intrusion/Intrusive Igneous Rock | Magma which cools and hardens in rock layers within the earth |
| Erosion | Exposes igneous intrusions formed within sedimentary rock layers |
| Extrusion/Extrusive Igneous Rock | Magma which cools and hardens on the Earth's surface |
| Principle of Superposition | In undisturbed rock layers, younger rocks normally lie on top of older rocks |
| Index fossil | Fossils of organisms that lived during only one or part of a period of time |
| Index fossils of the same organsim found in rock layers in different regions of the world | Indicate that those rock layers are the same age |
| Radiometric Dating | Method used to determine the absolute age of a fossil or rock |
| Radioactive Isotopes break down into | Stable Isotopes |
| Radioactive Decay occurs at | a constant rate |
| Half-life | Unit used to measure the rate of decay of a radioactive isotope |
| Half-life | The time it takes for half of a radioactive isotope to decay |
| Deposition | Process in which sediments are laid down |
| Observation | Based on using your 5 senses: sight, hearing, smell, touch, and taste |
| Inference | Conclusion based only on observations not experimentation |
| Replacement | Type of petrifaction in which the organism's tissues are completely replacted by minerals |
| Uplifted | Rock inside the earth is moved to the earth's surface |
| Composition | Chemical makeup of a rock |
| Texture | Quality of a rock that is based on the size, shape, and positions of the rock grains |
| Felsic Magma | Contains SILICON, aluminum, potassium, and sodium |
| Felsic Magma | Thick and Slow Moving |
| Felsic Magma | Produces light colored rocks |
| Felsic Magma | Examples are Granite and Rhyolite |
| Mafic Magma | Contains magnesium, iron, and calcium |
| Mafic Magma | Thin and fast moving |
| Mafic Magma | Produces dark colored rocks |
| Mafic Magma | Examples are Gabbro and Basalt |
| Intrusive | Produces rocks with large crystals and a coarse texture |
| Intrusive | Cools slowly producing large crystals |
| Intrusive | Examples are Granite and Gabbro |
| Extrusive | Produces rocks with small or no crystals and a fine or glassy texture |
| Extrusive | Cools quickly producing small or no crystals |
| Extrusive | Examples are Basalt, Rhyolite, Obsidian, and Pumice |
| Clastic | Type of sedimentary rock formed when rock/mineral fragements are CEMENTED together |
| Chemical | Type of sedimentary rock formed when solutions of dissolved minerals and water |
| Organic | Type of sedimentary rock formed from living organisms |
| Clastic | Examples include conglomerate, sandstone, and shale |
| Chemical | Examples include limestone and halite |
| Organic | Examples include fossiliferous limestone and coal |
| Contact Metamorphism | Occurs when rock is heated by nearby magma |
| Regional Metamorphism | Occurs when pressure builds up in deeply buried rock or when the Earth's crust collide with each other |
| Foliated | Mineral grains in metamorphic rocks are arranged in bands or layers |
| Foliated | Examples include slate and gneiss |
| Non-foliated | Mineral grains in metamorphic rocks are arranged randomly |
| Non-foliated | Examples include marble and quartzite |
| rock | Naturally occuring solid mixture of one or more minerals and organic matter |
| Charactieristics of an Index Fossil | Widespread, Abundant, and Easy to identify |
| Index Fossil | Used to determine relative age of rocks and fossils |
| Relative Dating | Process of determining if an object or event is older or younger than other objects or events |
| Geologic Column | Ideal sequence of rock layers containing all known fossils and rock formations on Earth. |
| Absolute Dating | Process of determining the actual age of an object |
| Isotope | Atoms of the same element, same number of protons, but a different number of neutrons |
| Stable | Isotope that stays in its original form |
| Unstable | Isotope that breaks down into stable isotopes |
| Unstable Isotope | called radioactive |
| Radioactive Decay | Process in which a radioactive isotope breaks down into a stable isotope |
| Half-Life of the Radioactive Isotope and Ratio of Radioactive Isotope to Stable Isotope | Need to know in order to determine the absolute age of a rock or fossil |
| Number of half lives a specimen went through is 1/8 is radioactive an 7/8 is stable. | 3 Half-lives |
| Number of half lives a specimen went through is 1/4 is radioactive an 3/4 is stable. | 2 Half-lives |
| Number of half lives a specimen went through is 1/2 is radioactive an 1/2 is stable. | 1 Half life |
