Mrs. Giorgianni/Physical Setting Earth Science UNIT II: EARTH’S MATERIALS AND GEOLOGIC HISTORY Main Concepts/Ideas: Matter is made up of particles whose properties determine their characteristics. Minerals have physical properties determined by the internal arrangement of their atoms. Rocks are composed of one or more minerals; the type of rock formed is determined by its origin. Geologic History can be reconstructed by observing fossils and correlations in the rock record. The age of rock materials is determined by analyzing the regular of decay (half life) of radioactive isotopes. Key Questions: How are minerals identified; and what gives them specific characteristics? What are the three main types of rocks and how does each of them form? How can we use the rock record to determine the relative age of rock outcrops? How are radioactive isotopes used to calculate the absolute age of rock materials? When did Earth begin to have an oxygen-rich atmosphere? Why? Vocabulary: Minerals Chemical Composition Chemical Properties Cleavage Crystal Fracture Hardness Luster Streak Igneous Rocks Extrusive/Volcanic Felsic Intrusive/ Plutonic Mafic Texture Volcano Sedimentary Rocks Cementation Clastic Composition Crystalline Structure Evaporites Fossils Organic Metamorphic Rocks Banding Foliated Intrusion Regional Metamorphism Contact Metamorphism Rock Cycle Classification Process Event Formation Geo History Correlation Half-life Index Fossil Unconformity Lab Activities: Observing Earth Materials Mineral Identification Igneous Rocks Sedimentary Rocks Metamorphic Rocks Sequence of Events Matching Rock Layers Radioactive Decay Homework Assignments: Week #4: Week #5: Week #6: Week #7: Week #8: Vocab: Minerals/Igneous Rocks, Castle Learning: Minerals Vocab: Sed Rocks/Met Rocks; Castle Learning: Rock Cycle/Rocks Vocab: Rock Cycle/Geo History; Castle Learning: Sed/Met Rocks No vocab; Castle Learning: Rock Cycle Review No vocab; Castle Learning: Geo History [ESRT pgs 8 & 9] Quizzes/Unit Test: Vocab quizzes will be given weekly based on the previous week’s vocabulary assignment. Quizzes will be given after each sub-unit: Minerals Igneous Rocks Sedimentary Rocks Metamorphic Rocks Correlation Radioactive Decay Earth Materials/Geologic History Unit Test o 25 Multiple choice questions – BRING A PENCIL o 5 Short answer questions Great spirits have always encountered violent opposition from mediocre minds. ~ Albert Einstein Giorgianni ~ Unit II Outline 2013/2014 UNIT II: EARTH MATERIALS/GEOLOGIC HISTORY Main Concept Review Minerals and Rocks 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. Minerals are identified by color, luster, streak, and crystal structure. Cleavage is determined by the internal arrangement of atoms. Density is Mass/Volume, and helps determine the identity of a mineral. V=M /D. The hardness of glass is about 5.5 The last page of ESRT has a mineral chart, including characteristics and uses of minerals. Note that the chart is divided into metallic and non-metallic minerals. Igneous rocks solidify from molten material, quickly with small or invisible crystals at the surface (extrusive) or larger crystals inside the earth, (intrusive). Igneous minerals are Mafic (dark) or felsic (light). See ESRT. Sedimentary rocks are formed from various sized sediments, and are classified on ESRT. Sedimentary rocks can form from deposition, burial, compaction, cementation OR precipitation. Deposition of various sediments, and therefore the formation of rocks, relates to water velocity. Obsidian is a glassy FELSIC igneous rock formed quickly at the earth’s surface. Pumice also forms this way, with air pockets within. Recrystallization and foliation are terms associated with metamorphic rocks. Metamorphic rocks are sometimes banded or very dense. Metamorphic rocks form from Heat and Pressure, either very deep within the earth (regional) or in contact with igneous intrusions (contact). It’s very important that you can use the rock ESRT’s for the three types. There is also a rock cycle ESRT, showing how rocks can change from one type to another. The only type of rock that contains fossils is sedimentary. Parent rocks are the rock type from which a metamorphic rock comes from. Again, read ESRT! Geologic History 20. The earth is approximately 4.6 billion years old, which is approximately the same as the half-life of Uranium. 21. The Geologic Time scale is based on fossil evidence. So is the theory of Evolution. 22. The Precambrian Era is sooo long compared to the others. The Cenozoic is pretty darn short. Humans have been around for far less the 1% of Earth History. 23. Half-life means the amount of time it takes for half of a sample of radioactive atoms to decay. Can you solve problems on this, and understand line, pie, or bar graphs? 24. Index fossils exist for a SHORT period of time, over a WIDE area. 25. Earth’s atmosphere began to have oxygen about 2 billion years ago during the early proterozoic as a result of photosynthesis in simple bacteria. Giorgianni ~ Unit II Outline 2013/2014