Correlation characteristics among mineralogical parameters in porphyritic granite bodies around Raghunathpur, Purulia District, West Bengal

The porphyritic granite bodies occurring around Raghunathpur have been stud ied petrographically to find out correlation characteristics among several mineralogical parameters with the help of systematic grid-sampling and moda l analyses. Q-A-P diagram clearly suggests that the porphyritic granite bod ies belong either to tonalite or quartz-rich granitoid. The quartz-rich gra nitoids of porphyritic granite bodies are found to have distinct spatial co ntrol. Average mineralogical composition of porphyritic granite bodies and nature of correlation amongst significant parameters have been worked out f ollowing statistical procedures. The correlations among different mineralog ical parameters however, yield poor values indicating the effects of assimi lation/granitisation/magma mixing. A fair degree of silica enrichment, impo sed on the crystallising magma parental to the porphyritic granite, has bee n suggested for its genesis, which is also corroborated by textural evidenc es.