Presentation on theme: "PreQuiz Describe the strength of bonds between atoms in a solid."— Presentation transcript:
1PreQuiz Describe the strength of bonds between atoms in a solid. What is a mineral?True or False: Only eight elements make up the bulk of the minerals found in Earth’s crust.What is the most common mineral group?carbonates b. silicates c. oxides d. halidesWhat are rock-forming minerals?What are some common properties of minerals?
23.1 The Rock Cyclerock- any solid mass of mineral or mineral-like matter that occurs naturally as part of our planetMixtures of minerals and sometime nonmineral material3 major types of rocks:IgneousSedimentarymetamorphic
4Summary QuestionsUse your own words to describe the sequence of processes that result in igneous rocks. Describe a specific example of a sedimentary rock becoming an igneous rock.Use your own words to describe the sequence of processes that result in sedimentary rocks. Describe a specific example of a sedimentary rock becoming a new type of sedimentary rock.Use your own words to describe the sequence of processes that result in metamorphic rocks. Describe a specific example of a sedimentary rock becoming a metamorphic rock.
5Igneous Rocks Formation Intrusive Igneous Rocks Rocks that form when magma hardens beneath Earth’s surfaceMagma- molten material below earth’s surfaceExtrusive Igneous RocksRocks that form when lava hardens on Earth’s surfaceLava- molten material on or above earth’s surfacegraniterhyolite
6Texture of Igneous Rocks Igneous Rocks are classified by texture and compositionTexturesCoarse-grained- slow cooling results in large crystalsFine-grained-rapid cooling results in rocks with small, interconnected mineral grainsGlassy- cools so quickly that ions cannot arrange themselves into a network of crystalsGlassy does not mean they look glassy!!! (pumice)Porphyritic- rocks experience different rates of cooling, so they have different sizes of crystals in the same rock
9Sedimentary Rocks Formation (5 major processes) Weathering- breaks rocks into sedimentsSediments- smaller pieces of rocks and mineralsErosion- movement of sedimentsAgents: water, wind, ice, or gravityDeposition- dropping of sediments because agent lost energyCompaction- squeezing or compacting of sedimentsCementation- dissolved minerals are deposited in the tiny spaces among the sediments
10Classification of S.R. Classified according to the way they form Clastic sedimentary rocks- made of weathered bits of rocks and mineralsGrouped according to the size of the sedimentsConglomerate- rounded, gravel-size or largerBreccia- angularChemical sedimentary rocks- forms when dissolved minerals precipitate from water solutions
11Features of S.R.The many unique features of sedimentary rocks are clues to how, when, and where the rocks formedLayers show the order in which the rocks formedFossils hidden in sedimentary rocks show evidence of past life formsRipple marks and mud cracks
12Examples of S.R.ConglomerateBrecciaSandstoneLimestoneRock salt
13Metamorphic Rocks Metamorphism- to change form Formation Agents Changes occur at elevated temperatures and pressuresConditions are found a few kilometers below Earth’s surface and extend into the upper mantleAgentsHeat- provides energy needed to drive chemical reactions, which may cause minerals to recrystallizePressure- may cause the spaces between mineral grains to close or cause the mineral to recrystallizeHydrothermal Solutions- hot water solutions promote recrystallization by dissolving original minerals and then depositing new ones
14Classification of M.R. Classified by texture and composition Texture Foliated-rocks with layered or banded appearancesFormed when rocks undergo intense pressures causing the rock to be more compact or even recrystallize the rockNonfoliated- rocks without banded appearancesContain only one mineral
15Contact vs. Regional Contact Metamorphism Regional Metamorphism When magma intrudes rockProduces low-grade metamorphism = minor changesEx: MarbleRegional MetamorphismDuring mountain building, rocks are exposed to extreme pressures and temperaturesProduces high-grade metamorphism = intense changes
16Examples of M.R.Parent rock- original rock before metamorphism takes placeMetamorphic RockParent RockSlateShaleGneissSchist, GraniteMarbleLimestoneQuartziteSandstoneSchistPhylliteAnthraciteBituminous Coal