GLG 115L - Miami University Midterm PDF

Summary

This is a geology midterm exam covering topics including mineral identification, rock formation, and textures. The questions cover different types of rocks and minerals, and their characteristics.

Full Transcript

GLG 115L - Miami University Midterm Study online at https://quizlet.com/_79esh4 1. What are the sev- Color/clarity, crystal form, luster, streak, hardness, cleav- en ways to identi- age, fractures fy a mineral? 2. How do you know The mineral will scratch the streak plate and make a whi...

GLG 115L - Miami University Midterm Study online at https://quizlet.com/_79esh4 1. What are the sev- Color/clarity, crystal form, luster, streak, hardness, cleav- en ways to identi- age, fractures fy a mineral? 2. How do you know The mineral will scratch the streak plate and make a white when a mineral streak of powder from the streak plate is harder than a streak plate? 3. What does a min- Looks like pages of a book, that split apart along flat eral look like sheets when it has one cleavage? 4. What does a min- Elongated prisms that fracture along short rectangular eral look like that cross sections has two cleav- ages that inter- sect at or near 90? Intersect not at 90? 5. What does a min- Shapes made of cubes and parts of cubes; if not at 90, eral look like that shapes are made of rhombohedrons and parts of rhom- has three cleav- bohedrons ages that interest at or near 90? In- tersect not at 90? 6. What are some of Tenacity, reaction to acid, striations, magnetism, specific the special char- gravity acteristics a min- eral can have? 7. Definition of Rock (heated until liquefied) that exists in isolated bodies Magma below Earth's surface 8. Definition of in- A body of magma that pushes its way into Earths crust trusion 1/6 GLG 115L - Miami University Midterm Study online at https://quizlet.com/_79esh4 9. How does in- When magma intrudes into Earth's crust, it will eventually trusive igneous cool to form coarse-grained intrusive igneous rock com- rock form? prised of visible mineral crystals What is another Plutonic name for intru- sive rock? 10. Definition of Lava Bubbly magma which explodes out onto Earth's surface at volcanoes 11. How does ex- When lava cool's on Earth's surface, forming a fine grained trusive igneous extrusive igneous rock which is comprised of tiny crystals rock form? What and/or glass is another name for extrusive Volcanic rocks? 12. Definition of fel- Light colored minerals, that usually refers to feldspars and sic minerals other silica materials 13. Definition of maf- Generally dark colored, usually refer to magnesium and ic minerals iron in their chemical formulations 14. Describe the col- Felsic or index of ig- Intermediate neous rocks from Mafic lightest color to Ultramafic darkest 15. Order of Texture Pegmatitic, phaneritic, porphyritic, aphanitic, glassy, vesic- from intrusive to ular, pyroclastic/Fragmental extrusive 16. Color Index from Quartz, Plagioclase Feldspar, Potassium Feldspar, Mus- Felsic to Mafic covite Mica, Biotite Mica, Amphibole, Pyroxene, Olivine 17. Describe fine grained texture; rapid cooling aphanitic texture 2/6 GLG 115L - Miami University Midterm Study online at https://quizlet.com/_79esh4 18. Describe phaner- comprised of visible crystals (coarse-grained); magma itic texture cooled slowly which let crystals grow 19. Describe peg- Very coarse grained formed by intrusive event; very slow matite texture cooling rate 20. Describe por- Igneous rocks that have two distinct sizes of crystals; large phyritic texture crystals are called phenocrysts, and the smaller more numerous crystals are called the matrix; Slow cooling followed by rapid cooling 21. Describe vesicu- When gas bubbles get trapped in cooling lava they are lar texture called vesicles; created extrusively 22. Pyroclastic tex- Composed of rocky materials that have been fragmented ture and/or ejected by explosive volcanic eruptions 23. What does a por- Indicates that a body of magma cooled slowly at first (to phyritic texture form the large crystals) and more rapidly later (to form the indicate? small crystals) 24. Glassy texture formed by rapid cooling and/or very poor nucleation 25. 5 characteristics 1) Naturally occurring of minerals 2) Usually inorganic 3) Definite chemical composition 4) Solid substance with specific crystalline structure 5) Distinctive physical properties 26. How are minerals 1) From molten rock formed? (4 ways) 2) From solution 3) Within living cells 4) By recrystallization 27. What are the 1) Euhedral = well developed faces, edges, corners three degrees of 2) Subhedral = partially developed crystallinity? 3) Anhedral = no faces, edges, or corners 28. 3/6 GLG 115L - Miami University Midterm Study online at https://quizlet.com/_79esh4 Definition of Tendency of minerals to break along flat parallel surfaces; cleavage reflects internal structure of the mineral 29. What is the dif- Fracture generally does not follow along a cleavage plane ference between a fracture and cleavage? 30. Sedimentary Burial and compaction rocks form as a result of.... 31. Sediments are.... loose grains and chemical residues of rocks, minerals, plants, or animals 32. How are sed- produced by the lithification of classic and chemical sedi- imentary rocks ment produced? 33. Lithification 1) Loose sediment is deposited process (3 steps) 2) Sediment is buried 3) Sediment is cemented "glued" 34. 3 Types of Sedi- 1) Clastic mentary Rocks 2) Bioclastic 3) Crystalline 35. Definition of Consists of rock fragments and/or mineral grains or both Clastic Rocks Derived from physical and chemical weathering 36. Definition of Bio- Consist of shell fragments and/or organic remains clastic (Biochem- ical) Rocks 37. Definition of Consist of mineral crystals precipitated from aqueous so- Crystalline lutions and/or chemical residues (chemical) Rocks 38. 4/6 GLG 115L - Miami University Midterm Study online at https://quizlet.com/_79esh4 Sedimentary 1) Weathering (physical and chemical) Rock Process(4 2) Transportation Steps) 3) Deposition 4) Lithification 39. Texture has 3 cat- 1) Size --> gravel (large) --> clay (small) egories... 2) Shape = angular --> well rounded 3) Sorting = degree of similarity in grain sizes, shapes, and mineralogy 40. What are the Gravel,sand, silt, clay, microcrystalline, and crystalline grain sizes in or- der? 41. What are the stoss = rounded, flatter part of a hill stoss and lee? lee = drop...side of the slope not moved by the wind 42. Definition of preexisting rocks that have undergone chemical and/or metamorphic physical changes while in a solid state (changes in min- rocks eralogy, texture, or change in composition) 43. What is the term Protolith used for parent rock? 44. Under what Heat (200-800 degrees which increases with depth) two environ- Pressure (4-15 kbar) which increases with depth ments will meta- morphism oc- cur? 45. Contact Meta- Rocks are exposed to thermal energy from a molten ig- morphism neous body Commonly produces non-foliated metamorphic rocks 46. Regional Meta- Rocks are subjected to directed pressures caused by morphism large scale tectonic processes 5/6 GLG 115L - Miami University Midterm Study online at https://quizlet.com/_79esh4 Produces foliated rocks 47. Foliation Refers to any planar (nearly flat) arrangement of mineral grains or structures within a rock; happens when there is equal pressure on both sides 48. Different types of Slaty cleavage = rocks break into thin slabs foliation (4) Phyllitic cleavage = alignment of platy (sheet-like) minerals into a layered structure (can't recognize minerals) Schistosity = refers to alignment of minerals like above where you can recognize the minerals Gneissic = refers t alternating dark and light layers (band- ed appearance) 49. Non foliat- Do not have planar structure (no foliation) ed Metamorphic Rocks Typically form during contact metamorphism Two common: marble and quartzite 6/6

Use Quizgecko on...
Browser
Browser