The Chemistry of Allanite from the Daibosatsu Pass

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The Chemistry of Allanite from the Daibosatsu Pass winerlogil wgzineD eugust PHHSD olF TW@RAD ppF RHQ±RPQ he hemistry of llnite from the hiostsu ssD mnshiD tpn ID I P I I I wF ryrsxy BD wF uswee DxFxsrshe DeFuyxy DwFrsws exh F eusee I hotorl rogrm in irth ivolution ienesD qrdute hool of vife nd invironmentl ienesD he niversity of sukuD srkiD QHSEVSUPD tpn P ghemil enlysis hivisionD eserh pility gentre for iene nd ehnologyD he niversity of sukuD srkiD QHSEVSUUD tpn efeg he rystl struture of llnite from grniti pegmtiteD the hiostsu ssD mnshiD tpnD hs een refined under the onstrint of hemil omposition determined y eletron miroproe nlysis of rre erth elementsF fkEstteredEeletron imges nd Ery element mps of the llnites show tht eh of their rystl grins hs hemilly homogeneous distriution of mjor elementsF e typil formul for the hemistry isX @g 8 A @v ge r xd m h wn HFWPH HFHVH IFHHH HFPQV HFRRQ HFHRV HFIHH HFHIW HFHRP HFHHV QC PC QC 8 A @el pe i A @el A@pe pe wn wg A @iy A@i y Ay@yrAF HFIHP IFHHH HFTHU HFHUT IFHHH IFHHH HFHSS HFHQU IFHHH R P U HFQIU HFSRQ HFQTS Ê he rystl struture of llniteD monoliniD VFWHS @IAD SFUTHT @SAD IHFIPQ @IA eD IIRFUVë@IAD spe group P GmD a PD hs een refined to n unweighted ftor of QFRT7 for IRSW oserved I refletionsF elthough the r tom position ws not determined on the hiffereneEpourier mpD inspetion of the ond vlene sums demonstrtes tht the r tom is uniquely loted t the yIH tom nd involved in hydrogen ond to yRF e systemti exmintion s to rystl hemistry of llnites suggests tht the isolted iy tetrhedron hs the lrgest distortion of three kinds of the tetrhedron ontining i y R P U groups in the llnite strutureF his oservtion is ommon to the epidote group minerlsD while the lrger distortion of eP sites used y oupny y ii in llnites ontrsts with the smller one of e sites in other epidote group minerlsF sn the llnite groups the ond ngles etween the yIHÿr ond nd hydrogen ond ryR re found to rnge from IUH to IVHëF gompiltion of the hemil ompositions of the title llnite nd the others from grniti roksD tpnD RC QC whih revels hEinorportion s the oupled sustitution of Qh C 8 @vnyA b Rii D provides n explntion for the oservtion tht higher h onentrtions hrterize llnites from the islnd rsF he ternry el y Epe y Eii digrm illustrtes tht llnites re groupedD ording to their P Q P Q originsD into three lsses suggestive of tetoni kgrounds for the rystlliztion lolitiesY @IA introntinentlD @PA islnd r nd @QA ontinentl mrginF uiyhX llniteD tpnD hemistryD tetoni settingD rystl strutureD iweF nd is found in gluophne shist @fnnoD IWWQA sntrodution nd grnet lherzolite s well @ng nd inmiD vvexsiD n epidote group minerl e PHHQAF here re lso llnite phenorysts in id e w i y @yrAX e a gD geY w a elD peD is P Q Q IP volni roks @eFgF whood nd rildrethD IWVQY known s hrteristi essory minerl in ghesner nd ittlingerD IWVWAF he lssi®tion of grniteD grnodioriteD monzoniteD syeniteD skrns irit @PHHPA permits llnites to e groupedD nd grnite pegmtite @eFgF heer et lFD IWVTY ording to their mjor ii ontentsD into qines et lFD IWWUY qiere nd orensenD PHHRAD llniteE@geAD llniteE@vA nd llniteE@AF wost llnites preferentilly inorporte the rdiotive elements h nd D s minor elements @heer et B iEmilX hossyUITdrsiFgeoFtsukuFFjp lFD IWVTAD nd so llnite often ours in the hysX IHFIIVHGHHPTRTIHSTWRHPSW 5 PHHS he winerlogil oiety wF ryrsxy i evF xgshimD IWTHAD exept for grniti llnite metmit stteF rowever report y roltstm et @uzuki et lFD IWWHA nd metmorphi llnite lF @PHHQA onluded tht nonEmetmit nd @ki et lFD IWVRY fnnoD IWWQAD were reported unltered ferrillniteE@geA from the fstÈs PC QC efore initil use of iweF everl uthors peEguEii deposit in wedenD gegpe elpe @udovkin nd ytenkoD IWTSY hollseD IWUIA @iy A@i y Ay@yrAD ontins neither h nor F R P U hve rried out struturl determintions of nonE feuse of the very lose sping of the Ery metmit llnites sine the ®rst re®nement of the lines in the v spetr of the iisD urte rystl struture of llnite y ed @IWSSAF eletron miroproe nlysis @iweA of iiE roweverD euse of the lk of urte iwe ering minerls is experimentlly hllenging of ii @eed nd fukleyD IWWVY xishid et lFD @eed nd fukleyD IWWVY xishid et lFD IWWWAF IWWWAD struturl re®nements of llnites hve not he modi®ed methods devised through reful een ttempted under the ®xed onstrint of their mesurement of these Ery lines hve improved hemil ompositionsF the qulity of the ii dt olleted y iwe he ims of this study re @IA to determine @eed nd fukleyD IWWVY xishid et lFD IWWWAD urte hemil ompositionsD resolved y where elerting voltge of PS k is pproE iweD of llnites from grniti roksD prite for quntittive nlysis of iiF reviously tpnese islnd rD @PA to de®ne rystl hemE pulished ompositions of llnites from tpn istry hrteristis of llnitesD nd @QA to provide @eFgF rsegwD IWSUY xgshim nd psqF IF yurrenes of llnite in tpnF RHR griws yp evvexsi geohemil kgrounds of tetonis on ourE renes of llnitesF ixperimentl methods yurrene nd rystl informtion he hiostsu ssD in northest mnshi refetureD tpnD omprises ertiry peliti hornfels @xgshim nd xgshimD IWTHA @pigF IAF ellnite ours s orseEgrined lk prismti rystl in the grniti pegmtite intruding into those roks together with qurtz nd few plgiolses @pigF PAF xery dykes ontin sheeliteD epidote nd ilmenite @xgshim nd xgshimD IWTHAF ome llE nites ompletely enlosed y qurtzD presumly less permele to ¯uidD tend to e in nonEltered nd nonEmetmit stteD ut this grniti pegmE psqF PF hotogrph of the unltered nd nonEmetmit tite is rdiotiveD s determined y qeigerE llnite rystl inluded in qurtz in grniti pegmtite wuller ounterF È from the hiostsu ssF elX llniteY zX qurtzY he llnite rystls rnge in size from lX plgiolseF IHTIHTPS mm to PTPTSmmFpigureQ shows the morphology of llnites from the urrentF he methods for seletion of the ii hiostsu ss nd the introntinentl region pek position reommended y xishid et lF @heer et lFD IWVTAF he introntinentl morpholE @IWWWA were pplied to the present nlysisX the u ogies of llnites @with some unertinty in the series of Ery spetr ws used for mjor minerl identi®tionA show tulr hit @rintzeD elementsY the w series for hY nd the v series IVWUY hnD IWIIY qoldshmidtD IWPHY roÈgerD for iiF wesurements of the v lines for D vD IWUIY heer et lFD IWVTAD wheres llnites from ge nd xd nd the v lines for rD mD qd nd the hiostsu ss re regulrly prismti nd hyD required no pekEoverlp orretionsF he euhedrlF present method for iwe of iiD exept for xdD hs een developed from tht dopted y ing et ghemil omposition lF @PHHQAF ilements deteted with qulittive nlyses ellnites were nlysed for mjor nd minor were mesured y quntittive nlysesF ellnite elements using the iwe @teEVTPIY tiyvA grins were nlysed quntittively for mjor equipped with three wvelengthEdispersive speE elements @iD iD elD peD nD wnD wgD gD hA t trometersF ulittive nlyses were mde using voltge of PS kD em urrent of IH neD nd PS k elerting potentil nd PSH ne em psqF QF worphology of llnites from @A islnd r nd @A introntinentl settingsF RHS wF ryrsxy i evF efvi IF tndrd mterils used for wvelength dispersive eletron miroproe nlysisF tndrd ghemil omposition element @wtF7A i iy @IHHFHA P i iy @IHHFHA P h hy @IHHFHA P el el y @IHHFHA P Q pe pe y @IHHFHA P Q n iy @QQFIIAD ny @TTFVWA P wn wny @QHFUTAD pe y @TWFPRA P Q wg wgy @IHHFHA g iy @SIFUQAD gy @RVFPUA P iy @SRFQAD el y @IPFUAD gy @PHFSAD y @IIFVA P P Q P Q v iy @SRFQAD el y @IPFUAD gy @PHFTAD v y @IIFSA P P Q P Q ge iy @SRFPAD el y @IPFVAD gy @PHFRAD ge y @IIFWA P P Q P Q r iy @SRFHAD el y @IPFUAD gy @PHFTAD r y @IPFPA P P Q P Q xd iy @SRFRAD el y @IPFVAD gy @PHFVAD xd y @IIFVA P P Q P Q m iy @SRFVAD el y @IPFWAD gy @PHFVAD m y @IIFPA P P Q P Q qd iy @SRFVAD el y @IPFIAD gy @PHFUAD qd y @IPFIA P P Q P Q hy iy @SRFUAD el y @IPFSAD gy @PHFTAD hy y @IPFHA P P Q P Q ground in n gte pestle until their powders were ount times of PH sF gonentrtions of ii were judged to e of suf®iently smll grin size to mesured t PS k with SH ne em urrentD nd ount times of PH sF foth em urrents were orreted with the followingX efvi PF hetils of dt olletion nd re®nement of llnite from the hiostsu ssF sntensity @speimenA u sntensity @stndrdA fem urrent @stndrdA hiffrtometer inrfExonius gehR fem urrent @speimenA Ê velength woEu rdition @l a HFUIHTW eA omposition @stndrdA emperture PWT u grystl size HFITHFITHFI mm here were two types of mesurement for the n mode oGPy present nlyses euse the nlytil error Ê VFWHS@IA e would e gret if ll elements were nlysed t Ê SFUTHT@SA e the sme em urrent @ hiym et lFD IWUPAY Ê IHFIPQ@IA e list of the stndrds used in this study is presented IIRFUV@IAë Q Ê in le IY nd ll dt were orreted with RUHFU@PA e pe group P Gm ep9 mtrixEorretion progrmF I P Py UH mx Ery powder diffrtion otl refletions SSSU nique refletions IRWV he degrees of metmitiztion for llnites were vlue HFHI int exmined y Ery powder diffrtion @hA nique p b IRSW H nlysisF mples were Eryed with guEu I Rs@p A H rdition @RH kD QH meA using igku p@HHHA SRWFS qeiger¯ex system with ¯t grphite monoE vlue QFRT7 hromtor nd Ië divergene slitF hole ptterns w vlue IHFRW7 qoodness of fit IFPV from S to TSëPy were snned t HFIëPy steps nd ÿI m UFVU mm the re¯etions in the PRFSÿPTFH nd QHFHÿQIFSëPy rnges t HFHIëPy stepsF he llnite smples were RHT P efvi QF etomi oordintes nd equivlent displement prmeters @eÊ AF etom x yz eq II PP QQ PQ IQ IP eI HFUSVS@PA HFUS HFISIS@PA HFHPIW@RA HFHPUP@WA HFHIWH@VA HFHPPI@VA ÿH HFHIPV@UA ÿH eP HFSWQUS@TA HFUS HFRPWPR@SA HFHPQQ@QA HFHPIS@QA HFHPSR@QA HFHPIT@QA ÿH HFHHUS@PA ÿH wI H H H HFHPRT@RA HFHPQI@VA HFHPQV@WA HFHPTH@VA ÿHFHHHP@TA HFHHWR@TA HFHHHQ@TA wP H H HFS HFHPHT@SA HFHIVR@WA
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