Nat sci minerals part1

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Nat sci minerals part1

  1. 1. . :: .r..., ,,-r n r ! ! :, *! i.l tI > ir fd{lut i : : !ti-I1 r /! l" i l-IIIi ffqNERALS Minerals: l" 1. naturallY occurrtng 2. homogenuous,solid : 3. cornPositicn not fixed) a. chenric:l (clefinite but.generally b. PtrYsica 4, orderecl aiorni.c ?fl?rrlerl€fltprrrcersses s. .trtrrrt f :rmel oy ill(lrganic sr"tbstances Mi neral oi rls - natttri:liy occurri n g 4]1ryThgf witrtout crYstalline structure *Tire orderly p.arterns ihat aton:s of elements assume in a rrineral is called iis crystallin u- stru cture br-rt different * Polymorplrs r ntinerals lra"ing the same composition/elernents crystalli;,e struc:t r]es I examPles: ir.-arcasite -; -* - Pvttqano -- -l . I Calcite atrd -.-,ragonite .---__ -^^^nrla I *Alias es: 1. Caiclte - islanl sPa; 2. FYrite - 1os11i clrld 3. Quart;. - ice cnilstals Georgius tgr:cola (Georg Barrer) D",f.q Metallica- , ..,,,, ,,, , ,i, ,, . , Optical Fic;:e*ies; 2- dotrble refrtl;tion :--- rr a sroup oi crvstai rrerar oytlrald unngu*rg"3,; consists fff:1":,oJ11J:1,. to the"j"ll::::,^oj t,,,,"r, Tii;i:*n.f,-nuuu the same relation physical properttes an* s:rintlettv ancl cltsPti ,-th* same chemical
  2. 2. because ;:[l are ui ;.erlain bY Iike atoms in the same geom€ afang€Tlent ex. pr,smatic cubic *Nicolas steno - pointed out that the angles between correspo.nding faces on of a nrine:tai [quartz] are always the same "rfttuft de ILsle * Rome of *Law of consta*cy of Interfacial Angles - angles between equivalent faces crystals of the .ru"l* substance, measured at the same temperature are constant. 2. crystal habit - e.iternal shaPe ex. botrYoidar, iihrous, grar"uiar 3: color - i: ti:e brightr.ess or Carl"ness of a mineral :r-,- -^-.-{-r.. spe -trum _. - resurl of ilie ieflection of light within the visible a. idroch,om:tic - ex. rruscovite (white or c.olorless), azurite (azure blue), rnalachite (green): sulfur (yellow) b. allochr:matic - ex quartz I 4. streak is the color qiven by a pulverized mineral eXa.hernatite:streak=reddish.brown/indianred | : color = red to black b lirronite : streak = Yqllow : color = bl-,wn right that is reflected frcm I re surface of a 5. luster - qual::, 3nd intensity of lnir,eral - can be lrouPed into: r a metailic - luster "rf untarnished rnetal; the usual characteristic of dark and opaque rninerals ex. nylite, golcl h. non-metallic - ir,utatl"rizes the colored nrir erals , , l :, , b. i resitrous - appearance of resin . b.; vitrer-rus - glass u.s ouiil"urti: b.4 adamantiire - diamond b.5 silkY - silklike b.i pearly - iridescent pearl-like lusJer.., grenJv u.z -rpp"ars to be covered wiil. thin layer of oil!iIIIIIx&
  3. 3. A*6. lrarciness - abiliiy of a rninerill to-withstand abrasion or scratching - in .licated in ternrs of the Mohs Scale of Hardnesscalcite qfluorite 14 -r5 diamond 1 hardestPractical scale:CLr-coin r;, specific gravity. - refers to the ratio of the weight of a volumeof material to the weight of an eclual volume of waier - spr:ing scale; hefting the mineral by hand ex.: | 2.65 feld 2.56-2.76 old 19.3 q. cleavage -,i:iers to the characteristic tendency.of mat,minerals tc spiii. c: sepa:ate easily along certain planes - govenred by interrial arrangement _ weak,:lssl a. .ype of brr cring c. boti a and b b. greater alomic sPacing rfect very good at 9C degrees to each other feldspar fair at 90 dectrees I9,n9-.--.--i at 56.dsgleeg !r 124 degree.- amohibole e Perleei-oei-ell A Oegrees; rhomboh perfect _ diamond nerft:ct sphalarite r v F
  4. 4. formed by the rreaking in the:g. fracture - refers to the nature.of ir"ofsurr"ce cleavage oir""i"n other than those the -i- quartz) a cort:hcidal (ex b ri;i;;;iitint"Y c irreguar hai;liY d - ^r ^r"^{rrral rnta: ruintiing or- l0.parting-breakingalongp|anesofstructuralweakness;resultoftt pressure nr ll.tenacity-resistarcethatamiiteralofferstobreakingcrushingbendirig tei ring eas.ilY a. brittle - breaks or powders , n tnuiiuuble - hammered into thin sheets with a knife c. sectile - can be cutinto thin shavings cl Cttctile - drawn into wire shape ;;ilL - n*nos but does not return to origina ". elastic f. 12. fluorescence artdt. phosphorescenee 4I magnetism 14. reaction to HCI , 5. taste 16. srnell 1l . striations
  5. 5. . CI.ASSIFICATION OF MINERALIE .I-CCORDING TO CHEMICAL GROUPS native elements old, sulfur, diamond oxides maqnetite, hematite sulfides rite, qalena sulfates carbonates calcite. dolomite hclsphates apatite silicates uartz, feld l- EIGHT MOST ABUNDANT ELEMENTS IN THE EARTHS CRUST 3.63 27.72 2.83 B.13 2.59 5X0 silica Tetrahedron . basic burlding block of the earths crust *polyrnerization Silicates - most abunCant mineral group r Feldspars - rnost abundant mineral (bl Silicon.Oxygen Tctraledron cxpandcd(rl Teuahcdron (d) Top view
  6. 6. Silicate Structuresorthosilcate or (sio4)nesosilicate independent SiOq grousorosilicate (Si2Oz) epidote, hemimorphite lir.king of 2 SiO4cyclosilicate (si6o16): beryl , rinq silicatesirrosilicate chain silicates sinqle chain (Si roxene double chain SjaOrr amphibolephyllosilicate (si2o5)- sheet silicatelectosilicate quartz, feldspar framework t COMMO}{ ROCK-FORMING MI NERALS1. quarlz 6. mica I I2. feldspars3. nephelilg amphibole4. sodalite 9. olivine5. leucite
  7. 7. 4.1 lGNDOus R(Juri"u ,lDefinitions: t ut mrnerals ^r niaterials whiclr maybe conposeo . -*.. cfrnred, r:onsolidated lirlocirs - r1:ltursuv ::il;;i.;;r, glass or a cornbination of these rocxoiganic ttiatter, of and solidification "ig7lf$" fire) - fgrrned by direct crystaUiztrtion Iglteorts roclcs:fLatin nlilgttt Magntu - "l{llr,acled nrixttrrd E l,s gi il ile;tuilssleri$ii - rnol:ih t*.,?f, sases -1,:, ,lTilo",,u*d r:l:?:51 tlissslvecl ii the upPer rnantle cnist: or in rhe upper rnar due to Jtltrtr partial *atiie tqtiwer forr:retl n o "*uti ;;i;;,;ic - iieat,anrl/ot decreasT:.[:Tlfapped the earths cnrst lruithrn on tho earths surla( -;.;,i;;l.placecl -;;,;;n.,,. cltnmbers K, *,*;r{:L::::f;j::,t,# l,"f,fNa - S(Oi - PnllclPat -r ^: uirlo*tv and explosive characteristics - <rjssalvecr gases ;;;ii;:;riiu,*",r 6i]0- 1200C - rilnfie t"nt1t"*tit"J ,f SOz - ,]"rir, LI20-,:aPor, COr, - Xlrvn Lli.ir.r-,j:,Pgg " 50% Si0z n. tltsnltic Inagmfl . t:900-12C0"C highlY fluid eolr6Y, sloa l"t. Grnnitic nraEitna T: lower than B00oC - highlY viscous l.Ld.tiri,--nn{erysldliaglstr . of change" -o;j-"tiy series -c^L^n i:.i.aciion $eries = J- ,1".,-tts Reactiorr Series .,i. , ., is graduallY " r in whish theearlier fornred inrler$s rnrgmafbr ;;i i i; :il:r:; il; #oi;" rm trre "t :; n ll; tthe mineral -*:iiil1: :, : Tf , tt,rti.*. in
  8. 8. ex.: plagioclase (Ca-rich torl(rich) f.)iscontinuous Reaction Series : reactiorr in which an early crystallized mineral reacts to form with the remaining licluid which constantly. changes its conrposition during cooling ancther mineral ex.. ii,,,, Enstatite + + Forsterite Melt 2 Mg SiOr MgzSiOa SiOz Magmatic ;lifferentiation : a general piocess in which the original magma with its full .ung. of cornponent elements is separated into rocks of different mineral composition a. fractionation b, filter o:essing. c. assimilation of the wall rock d. magnra-mixing Morlqresl-af.tnsglqa a. external.forces - sqrteezing of rnagma chamber and causs filter pressing b. internal forees - gur **punsion; stoping (magma move along fractures until they engulf the ho$ rock) tgnerrus rocks , - 80% of the mass of the earths crust - Genetically classified into rr| a. plutonio: intrusivb li, volcanie = extrusive I c. liypabyssal - Mineralo$ically: a, felsic - large proportions of K-feldspar and Na-plagiocl456 + quartz b. mafic - Ca-plagioclase, large hmounts of{endrnagnesian mlrerals but little quartz or K-feldspar c. ultramafic - composed entirely offerromagnesiatt rninerals with minor amounts of feldsPars - Major textures Textirre Dcscription Interpretation Phaneritic grains visible to the relatively slow cooling naked eve Aphanitic grains not visible to relatively fast cooling the naked eye _ _ Forphyritic some grans coarse, two cooling rates others line (phenocryst, sioundmass/matrix)
  9. 9. no minerals fonled r id s"tft; co4llg witElgSie eg 9XMost Abundant lgneous Rocks #- Intrusive Extrusive feiric r" ck[ K.ftiltdMptfiioclase, qtr arte, less Granite Rhyolite amountp of biotite or ampbibqle-. -. . Diorite Andesite ffie(30-50% anorthite), a,rnphibole,, (quartz may be present in gqoi*. "tGali,bro- Basalt amounts of olivine s.trapes brrfiirtiilve rock bcdies of its size or shape" Flutoir =any llass of intntsive rrrck regardless a. batholiths b. :tcsks c, dikes d. sills I e. lacolith f. tupolith (mining): gold district imflb rlancb: r.retaliic and non-metallic minerals L. : -" :- i ( 5.1 Yolungoes !- ro!r:n:io : a vdni which connects a reservciir of maguu in the deptlis of tlie earlhs crust with the surface of the earth : ejc"ts lava, fragmentaVpyrociastic rocks and gases : cons (volcanic edifice) A. Lava nffiu that h1S reached the surface of the earth different compositions ancl temperatures iesulted into lavas with a rango of physical - properry (i.e., riscosity) and fcafules. a.. paloeho* riua -:t:glly fluid, T = 1000"c; thin; smooth, biilciwy, ropy suilace b. aa l.vr - fi-il; iini.guq $low moving; seu*rh neters thick;rough : "ibtlu$; jugg*d, sPinose c. pittorv-,ta.iu1"-Iffii;pted under water or ice; (toothpaste-like)
  10. 10. I .fa ,l ll. F!rqginstic materials blown-out from a volcanic vent under pressure or -:il:,:m#*ffffiT$rrue**,smagma the raoidlv expanding gases present in plsstic state - rr*tpoi.d eitfiei+n in solid or of the fragments - classification in telTns of sizes and shapes - older lavas r a, blocks - > 64 mm; pieces of crustal layers or the congealing of blebs tllj:d ..j:a b. bombs - > i4mm; spindle/spherical masses from Iava b"l bowdung "i bz breadcrust b3 armored ,0 c. lapilli -2-64 mrn; saccretionary lapilli 4 ash-<2mm glass) +*r- Pu,nice, scori&, obsidian (volcanic T: .;, of pyroclastic rocks and lava ..:,ts, domppsite/strntevolcnnoes: altemntingla-yers Mont PelptKrakatau ex.. Mt. ttu.ii, V.r,,nius, Stromboli Etnq Mayon : a higtrly hh?{ gas charged with incandescent i nuee srdente (glowine cloud) ,rt porti"ie, ,oitrut i, i"g"*ii*r u *ouile ernulsio--n ydtidense enough to maintain lntact with surface r.ldera - co.llapsed volcano (ex Taaf,Laguna Bay) .;r .:ir comPo$ed of solidified lava flows; b. Shield ".olcailoes - broad, gently sloping.v-;rcantjes rarelY stePPer than,f:dtigrees ex. Mauna Loa : , a il. Cindur cones - volcano that is constructed of loose fragmentilpyroclastics;slopes about 30-33 degrees ex. Parictrtin BELT - PACTFIC RING.OF FIRE/CIRCIJM-PACTTTC Type of Volcanic Eruptions: -rr --^,.-|.^.rri.onh,erl gases .,cq.eq *. influencealfnir"ority of the magma aitd a{nourlf oi dissolved - .iolencs" ,*pii* i, ,rtuit io ,rr" o*gree of fragmentation and the distance "r.n quiet liberation of gases a. Fflaw*iian - ubundant outpouring of lava flows; lava fountains;
  11. 11. and scoria b. Stnoxnholinn - milil, explosive eruption of pasty, incandescent bombsql, accompanied by a white vapor cloud; discrete explosions c. vutrcaninn - btsw-out of solidified cnrsts (over the crater); acbompanied by a great- - lavaflows may ;;;iifl.wei shaped eruption cloud containing an abundanco of ash; issue d. Flininn - eruption of extrerne violence; gas-blast eruption; eruption cloud resembles an spreading out); huge Italian stone pinetree (shooting upward of the column then sustained eruPtion column Felean - extreme explosiveness; nuee ardente Phneatic g F.trreatomagmntic l h. Uliru-Ptiniatr - excessive emission of ash resulting to negative landforms lLE n*Vqlpgnlg-Hazards ( c. lava flows e. caldera collapse a. ieplua fall d. lahars f. tsunami b. pyroclastic fhll lrnportnnt: geothermal energY (ex. Makban, Bacman, Tiwi) s[rMM3nY lava fottntains
  12. 12. :,t,il,i .. j,::, r. i.:r: .il..l_,1 ffi ffi i+:ir :ri,i .i;i b9& oir 5 L)-rr #6p ! I !Ii:r;;i i ?.ii:li,iiii-ig btj;iEln Z .Ei.i.i1.1 Y Iiili$[ 6 0, (s E E z I {}::r li:i; l:i+.i ::: olii :i .E r, l:..ir. i tr...:+i o = d 0) o) o .c. 6@ 7 -rao q LY:t !i:t
  13. 13. ,i iii wil,ATr{rcntruc nivn ER,osnoNiVE,:XI.!!Eit,lNi- is the physical disintegtation arfci r,hernical decontposition by ivhichrocks iire changed upon exposure to "agents" at or near the earths surface, with little orno lranspo;t of loosened or altercd Inateriai *- agents - hydrosllhere, a-tmosphere, biospher-e.4. l4cch*nical Weathering - is the breakdown. of rccks into smaller fiagnents byvatious ph1151"1 stresses - ::tictly a lthysicul ploces:; willxnt a change in chemicalc1tilP)riliott fr4 erhilnicaN Weath ering Frocesscs a. ice wedging/ttost wedging b. salt crystal gror,vth L:. slrceting/unloading - releasc of confining p:ressure exfoliation - fonnation of cprved sheets of rock by release of pressure d. anirnals and plants e. tlrermal expansion and contraction - seasonal/daiiy temperature changestr]. Chenrical Wcattering- is the process"by rvhich chenrical reactions transform rocksand nrinerals into ne;, shemicat cornbinations that are stable under conditions prevaillng ator near the earth"s sur{-ace lioie: more ef-fectittc itt xarmer clintcle:i - lrcat increase,s tlw xtte of ma:;t reucf irnts Chcnricnl Wcatherinq Proccsses a. Flydrolysis - H or Otf of the water anAffinUe ions of the rninerals Ex. I(-ibldspar 2l(Alsi?o8 + 2tt2co3 -F 9FI20 Ortlroclase Carbonic Acid Water Al2iii205(ot-t),r -l- 4l-I4sio4 J- ?tc + 2{-ICo3 Kaolinite Silicic Acid Potassium Ion Bicarbondte l.on {, :--*ffi
  14. 14. . ,1; l). ulSSOllltl0n - Fr2U -- --Llnlversat solvent Ex. b.l NaCl T HzO Na -F CI 1- FLO b.2 FITO COz -,----+ HzCOr CaCOr T FizCOr ------+ Caun F 2HCO:- c. Oxidation * is the cornbiration of oxygen ioris ivith cations Ex. 2FeSz + 7O:r + zHzO F 2Fe- + 4SOt + 4F-t+ 4Fe* -t- oz {- 4# -_|4FErrr + 2H?Ogl&qlar dalrygolbstlqg or "onion-skin weathering" -- produces spheroidal boulders ofrelat ively untveathertd materialX{.esults/f roducts: a. regolirlr - fragincntal and uncor.rsoiidated rocl< material that has coarse grains rvith angular edges and a composition sinrilar to the unweathered rock " b. very large increase in the surface area of the v/eathered rnatedal , f,,. soluble rnaterialsXlilr:tons afTccting the nntes o{ weathering:I. susceplibility otthe consl-ituertt roirrurals to rveatltering - Goldich Stability Series -- nrinerals forrned at liigher temperatures and pressures tend to be less stable in uveathering environment than those formed at lower temperatures2. climale or intensity of the weathering processes -- total amount of precipitation - intensity olrain -- sr:asonal variations -- infiltration -r -- run-ofland rate of evaporation -- teulperaturerwnnn, hunrirlclimate Vs. coid clirnaLe -J. amount olsrrrface exposecl to the atmosphefe f,i?0$/Ory - forcehrl physical removal of material frorn ihe parent rock, alwa.gs acconrparried by transportat.ion and eventually end in deposition a. running vrater d. ivind f- mass wasting: : b. grouncl water €.waves ald currents g. oigarric activi c. glaciers
  15. 15. " n Dcpositio n itrtti [ix.hiticatiorl : I I l-- Lithifliq:ation - is the term for p group of processes tlrat conrreft loose sediments into sedirlen.rarr/ rocks u. C1:me6talion - the process by which sediments are convefted ilt<i roclr by the cliemical precipiiation of rnineral material / cqment among the grains of the sediment I + silic.r, carbonates and irolt oxides t{ is tlie loss in over-allvolunie and pore space as sedinrent t-, . Ccrnpactittn = particles are packed closer together by the weiglt of, overlying rnaterial Cry:;tallization - refers to crystal developmelit and growth by precipitation fiom solution; no cement; grains are held together by inierloclcing crystals Ser{inrept:ltion - tlre process of fornring sedinqnt in layers, including ttre separation oi rocli partioles fitlnr the palerrt Inaterial, transportation of these pa.rticles to the site o.l deposirir:n, actual cleposition/setiiing, litlrification and consolidaticn into rock,
  16. 16. . SEDIMEhITARY ROCKSSedimentarY Rocks:- Latin woi-d, sedimentum = "settling"- formed from consolidation of materials from pre-existing rocks, fromprecipitation and from secretion of organismsSediments - finely divided matter consisting of mineral grains and organic processes,.transported bymatter derived from pre-existing rocks and from lifeand deposited from alr, water or ice - origin: (1) weathering and erosion of pre-existing rocks izi cnemical prebipitation from solution (3) secretion of organisms Ocean = ultimate destination Partlcie size classification for sediments [dden-Wentworth Common Size Glass . Sedimenf Narne Particle Name Gravel or Rubble 1116-2 1/256-1/16 Two Maior Textures of Sedimentary Rocks . and particles 1. clastic [Greek k/asfos, "broken"] = discrete fragments crystal pattern 2. non-clastic texture = minerals forming an interlocking .
  17. 17. Iypes of Sedlrrientary Kocr(sa. Detrital sedimentary rocks.particle size is the primary basis UOOenlWentworth Common Detrital Rock Size Class Sediment (Particle Namq)- Name Boulder Gravel Conglomerate UI Cobble Rubble Breccia Pebble Granule Sand Sand Sandstone sitt Mud siltstone Shale or mUdstone Clay clavstone precipitation of minerals b. chemical sedimentary rocks: formed by direct from solution. *Precipitation occurs in two.ways: (1)lnorganicprocessessuchasevaporationandchemica| actirTity can produce chemical sediments - iximprei: dripstone and halite (salt) (2) Organic processes of water-dwelling organisms form biochemical sediments Texture Composltton Rock Name Group Clastic or non- calclte, u?uu3 Limestone clastic Non-clastic Dolomite, Dolomite (Dolostone) lnorganic CaMq(COs)z Non-clastic MicrocrYstalline Chert quartz, SiOz Halite, Rock salt Non-clastic NaCl Gypoum, RocK gYPsum Non-clastic CaSOo2HzO Clastic or non- Calciie, CaCOg Limestone Organic clastic Non-clastic MicrocrYstalline Chert ouartz, SiOz Torc6sttc Altered Plant Coal remains
  18. 18. -..SedimentarY $tnuctu res environment*provide additional information with regard to the depositional :rmed as bedding or stratificationl1, l-aYering [also t( :l layer is 1 cm or more 1.1 strataor bed: thickness of tftu l.2taminafion:thicknessofthelayerislessthanlcm (e.g., change in *may result from differences,Qetween |ayers in texture color or cementation grain sizeiti*iui tomposition -beddingptanes.=flatsurfaces.alongwhichrockstendtoseparate and the beginning of e end of one episode of sedimentation another (b)pauseindepositioncanleadtothecreationofbeddingplanes 2Ripp|emarks.=smatlridgesofsandformedbymovingwindorwater 2,lCurrentripp|emardE:lfairorwaterismovingessentiallyinone direction 2.2oscillatoryripplemarks:Resu|tfromtheback-and-forth movementofsurface*.u"inshal|owwaterenvironments 3Cross.beddingisanarrangementofsmallbedsatanangletothemain sedimentarY laYering by a Progressive 4. Graded bedding is a tYPe of bedding characterized through the bed decrease in grain size upwaid 5Mudcracksarepolygonul",.u.k,thatformwhenmudshrinksasiidries
  19. 19. fiNETAMOffiFffiC RCCKS Metarnorphic rocks = rocks resutting from changes in temperature and pressLtre ancl frotr changes in the chemistry of tlreir poie fluids. = can be formed from igneous, sedimentary, or previor-rsly nretanrorphosed rockb. = solid-state .reaction = consist of a fabric of irrterlocl<ing crystal grains, usually with preferred grain orientation. *Changes new minerals, textures and structures -,,.t.* -) occur in the solid rock; witltout melting of rock I. Principal agents of metamonphisrn a. lentperature - rarely below 200oC, upper limit is ihe meltingtemperature of tlte tock b. Pressurcil b.1 confiping/static = pressLr-e applied equrally on all surface of tlre BT5r"r, ecl/dynamic - pressLrre applied unequally on the surface of a body b.2.1 compressive - flattens objects perpendicular to applied pfessLl[e b.2.2 shearing flattens objects parallel to tlre applied pressLlre *Fcrliation parallel arrangement of textural or structrrral features - in apy type of rock; planar structure that results from flattening of tlre constituent grains of a metamorphic rock c. Chentically active/migrating f/uids - loss and gain of ions and atoms - snrall arnir-rnt of pore fluid provides an inrportant medir-rrn of transPotl Mletasornatisln

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