13 Self- directed Exercises Lecture a ternary phase diagram PDF

Preview

Summary

Download 13 Self- directed Exercises Lecture a ternary phase diagram PDF

Description

Reading a ternary phase diagram Aternarydiagramisatriangle,witheachofthe threeapexesrepresentingacomposition,suchas sandstone,shale,andlimestone.ForthemomenttheyarelabelledA,B,andC.Wearegoingtotake thediagramaparttoseehowitworks.  Thedrawingtothelefthasonlytheskeletonofthetrianglepresent as we concentrate on point A. Point A is at the top of the heavy vertical redline(arrow).Alongthis lineisindicatedpercentofA.A point plotted at the top of the vertical line nearest A indicates 100%A.Ahorizontalbaratthebottomoftheline(farthestfromA) represents0%ofA.Anyotherpercentagecanbeindicatedbyaline appropriately located along the line between 0% and 100%, as shownbythenumbersofftotheright.  Thehorizontallinesthatrepresent various percents of A can beof anylengthsince theyrunparalleltothebaseline andremainthe same distance from the bottom and top of the triangle. The lines are projected out to the right of the red arrow line just as far as where the imaginary side of the triangle will be, and their percentageabundanceswrittenalongthe rightsideofthetriangle. By doing this the right side of the triangle becomes the scale for percentabundanceofA.  To be complete the horizontal lines also extend to the left until theycontactthe leftsideof theimaginarytriangle,but nopercent abundancesarewrittenthere.Inthefinalternarydiagramthered verticalarrowisremoved.  Point B is at the lower left apex of the triangle. We construct a percentabundancescaleforBbyrotatingtheheavyred scaleline 120degreescounterclockwisesothatitrunsfromtherightsideof the triangle to the lower left corner. The right side of the triangle nowbecomes thebaselinefor thepercentscaleforB,andaseries ofredlineshavebeendrawnparalleltothetriangle'srightsideto markoffthepercentages.Theselinesareprojectedout totheleft and bottom sides of the triangle, and the percent scale for B laid outalongtheleftside.  PointCisatthelowerrightapexofthetriangle.Weconstructthe percentabundancescaleforCbyrotatingtheheavyredscaleline another120degreessothatitrunsfromthe leftsideofthetriangleto the lowerrightcorner,and thepercentscalelinesandpercentabundancenumbersrotatewithit.  Thesumresultistheternarydiagramtotherightwithallthescalespresent.Notethattheheavyred lines are not included in this final triangle. Also observe that the ternary diagram is read counter clockwise.  

So,somepractice.Notethenumbers1‐4onthediagram.The compositionforeachofthesepoints isshownbelow.Seeifyouagree.  1.60%A|20%B|20%C=100% 2.25%A|40%B|35%C=100% 3.10%A|70%B|20%C=100% 4.0.0%A|25%B|75%C=100%  

   However,incommonuse,ternarydiagramsusuallydonothavethe"AScale","BScale","CScale"on them. Also, even the percent numbers are absent. So, you must learn to read these diagrams withoutallthoseaids.                Reference:http://csmres.jmu.edu/geollab/fichter/SedRx/readternary.html...