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1、实习五岩浆岩（一）中酸性岩目的：1、学会岩石的鉴定和描述方法2、掌握岩浆岩的结构、构造类型3、认识几种主要的岩浆岩类岩石内容：1、观察并描述：花岗岩、似斑状花岗岩、花岗斑岩、流纹岩、伟晶岩、浮岩等2、观察：细晶岩、黑曜岩、珍珠岩、花岗闪长岩等岩石Rocks岩石：矿物的天然混合物或集合体。RocksarenaturalmixturesoraggregatesofmineralsHowtoIdentifyRocksRockscanbeclassifiedasigneous,metamorphic,orsedimentaryaccordingtothemannerinwhichthe
2、ywereformed.Theirspecificcharacteristicsdependonthemineralsthatconstitutethem.Basedonthisinformation,itispossibletoknowhowrocksgainedtheircolor,texture,andcrystallinestructure.Withalittleexperienceandknowledge,peoplecanlearntorecognizeandidentifysomeoftherocksthattheyoftensee.ColorThecolorof
3、arockisdeterminedbythecolorofthemineralsthatcomposeit.Somecolorsaregeneratedbythepurityoftherock,whereasothersareproducedbytheimpuritiespresentinit.Marble,forinstance,canhavedifferentshadesifitcontainsimpurities.TextureTexturereferstothesizeandarrangementofgrainsthatformarock.Thegrainscanbet
4、hick,fine,orevenimperceptible.Therearealsorocks,suchasconglomerates,whosegrainsareformedbythefragmentsofotherrocks.Thetextureisasmall-scalepropertyofarock,butdeterminedmanyofitslarge-scaleproperties.MineralCompositionRocksarenaturalcombinationsoftwoormoreminerals.Thepropertiesofrockswillchan
5、geinaccordancewiththeirmineralogicalcomposition.Forinstance,granitecontainsquartz,feldspar,andmica;theabsenceofanyoftheseelementswouldresultinadifferentrock.TheThreeGreatRockFamilies三大岩类：Sedimentary：沉积岩Hasobviousstratification层理Verysoft(easilyscratchedbyaknife)软Obviouslymadeofparticlescement
6、edtogether碎屑被胶结在一起Containsfossils化石Igneous-Volcanic火山岩Containsnumerousbubble-likecavitiesthatmayormaynotbelinedwithminerals气孔Hasobviousbubblyorfrothytexture气孔Isfine-grained,uniformintexture,andhard细粒、均匀、坚硬GlassyorhighlyvesicularrocksarealmostalwaysigneousIgneous-Plutonic侵入岩Madeofdiscretemine
7、ralgrainslockedtogether(maybeloosenedbyweathering)Containslargecrystalsinafiner-grainedmassRockmassobviouslycutsacrossotherrockstructures.Metamorphic变质岩Hasafinetexturewithanobviousdirectionalgrain(foliation)定向Hasobviousbands,streaksorclumpsofdiffer
