Mineral Analysis
The Canadian Mineralo gist Vol. 32, pp. 919-933 (1994)
MINERALRECOGNITIOINDIGITALIMAGESOFROCKS:
A NEWAPPROACHUSINGMULTICHANNECLLASSIFICATION
PATRICKLAUNEAU* ANIDALEXANDERR.CRUDEN DepartmenotfGeol,ogEy,rinilnteCollegeU,niversitoyfTorontoM,ississaugOa.ntariPISL1C6
IEAN-LUCBOUCHEZ
LaboratoiredePCtrophysiqucet Tectonique,Universit€Paul Sabatier, 38.ruedzTrente-Sit-Ponts3,1400ToulouseCedetFrance
AssrRAcr
Digital image-analysisis usedfor counting(modalanalysis)andmeasuringgrains(textureandfabric analysis). Traditionally, minerals are visually recognized and manually outlined prior to digitizing aud subsequentanalysis. This limitation can be overcomeby using multichannelmethodsoi classification,in which the minerals in multichanneldigital i-agesareaccuratelyrecogpi;donthebasisoftheiruniquespectralorelementalsignaturese,stablishedbyatrainingstage prioi to classificatioir.fnJtecnnique is appliedherefor ttremoAAanalysisof three-color,electro-opticalimagesdigitized usingCCDvideocamerasandscannersa,ndmulti-elementalX-raymapsacquiredwithanelectronmicroprobe.I,1allthree casJstudiesof the analysisof plutonic igneousrocks, the resulting mineral modesare sufficiently preciseto identify signifi- cantcompositionalheterogeneitiebsetweengroupsof samplesand in thecaseof X-ray elementmaps,to quantifythedegree andtypeof alteration.
Keywords:digital images,multichannelclassification,electro-opticaldevices,electronmicroprobe,X-ray elementmaps, modal analysis.
So\aM^q'IR.E
L'analysed'imagesnum6riquesderochesestutjlis6epour calculerdessurfaces(analysemodale),compt?rdesgtains (granulom6trie),meJurerleur forme et leur orientation(analysede textureset de fabriques).Habituellement,les min6raux d"oivent6treaupr6alableidentifi6setdessin6sparl'op6rateuravantd'Ctrenum6ris6spourI'analyse.A cetteidentification longueetlaboriiuse,il estpr6f6rabled'utiliserdesclassificationsmultispectralessemi-automatiquesr,apidesetobjectives.
MINERALRECOGNITIOINDIGITALIMAGESOFROCKS:
A NEWAPPROACHUSINGMULTICHANNECLLASSIFICATION
PATRICKLAUNEAU* ANIDALEXANDERR.CRUDEN DepartmenotfGeol,ogEy,rinilnteCollegeU,niversitoyfTorontoM,ississaugOa.ntariPISL1C6
IEAN-LUCBOUCHEZ
LaboratoiredePCtrophysiqucet Tectonique,Universit€Paul Sabatier, 38.ruedzTrente-Sit-Ponts3,1400ToulouseCedetFrance
AssrRAcr
Digital image-analysisis usedfor counting(modalanalysis)andmeasuringgrains(textureandfabric analysis). Traditionally, minerals are visually recognized and manually outlined prior to digitizing aud subsequentanalysis. This limitation can be overcomeby using multichannelmethodsoi classification,in which the minerals in multichanneldigital i-agesareaccuratelyrecogpi;donthebasisoftheiruniquespectralorelementalsignaturese,stablishedbyatrainingstage prioi to classificatioir.fnJtecnnique is appliedherefor ttremoAAanalysisof three-color,electro-opticalimagesdigitized usingCCDvideocamerasandscannersa,ndmulti-elementalX-raymapsacquiredwithanelectronmicroprobe.I,1allthree casJstudiesof the analysisof plutonic igneousrocks, the resulting mineral modesare sufficiently preciseto identify signifi- cantcompositionalheterogeneitiebsetweengroupsof samplesand in thecaseof X-ray elementmaps,to quantifythedegree andtypeof alteration.
Keywords:digital images,multichannelclassification,electro-opticaldevices,electronmicroprobe,X-ray elementmaps, modal analysis.
So\aM^q'IR.E
L'analysed'imagesnum6riquesderochesestutjlis6epour calculerdessurfaces(analysemodale),compt?rdesgtains (granulom6trie),meJurerleur forme et leur orientation(analysede textureset de fabriques).Habituellement,les min6raux d"oivent6treaupr6alableidentifi6setdessin6sparl'op6rateuravantd'Ctrenum6ris6spourI'analyse.A cetteidentification longueetlaboriiuse,il estpr6f6rabled'utiliserdesclassificationsmultispectralessemi-automatiquesr,apidesetobjectives.