Current Science

Open Access Open Access  Restricted Access Subscription Access

Spectral Response of Few Important Textural Variants of Chromitite and its Potential in Estimating Relative Grades of Chromitite – A Case Study for Chromitite of Nuggihalli Schist Belt, India


Affiliations
1 Geosciences Group, National Remote Sensing Centre, Indian Space Research Organization, Balanagar, Hyderabad 500 625, India
2 Department of Geology, University of Calcutta, 35 Ballygunge Circular Road, Kolkata 700 019, India
 

We have collected, processed and analysed the reflectance spectra of representative chromitite samples of spot type, clot type and disseminated type textural variants to understand the diagnostic spectral features of each of these samples. We have found that the reflectance spectrum of each textural variant is distinct from the spectra of other variants despite having few common absorption features. Spectral features of chromitite samples are governed by the spectra of two dominant minerals, chromite and chlorite. Spectral features of chromitite at 550 nm and 1100 nm are governed by electronic transition process in Fe3+ and crystal field effect in Fe2+ ions present in chromite structure respectively. On the other hand, spectral features at 1400 nm, 1900 nm and 2300 nm are related to the vibration of O–H, H–OH and metal hydroxide bonds in chlorite. Amongst these features, the spectral feature at 1100 nm (due to Fe2+ in chromite grains) is common to all three major textural varieties of chromitite samples studied here. Electron probe micro analysis (EPMA) data of chromite and chlorite grains of each texture are used to relate the presence and abundance of Fe2+ (in chromite grains) with absorption feature. Width of the 1100 nm feature has a correlation value 0.95, while depth of the same feature has a correlation value 0.94 with the abundance of chromite mineral estimated using modal analysis of chromite samples. Therefore, spectrometric parameter of 1100 nm spectral feature of chromitite can be used as proxy for estimating modal abundance of chromite in chromitite samples after estimating deposit specific correlation coefficient.

Keywords

Chromitite, Electronic Processes, Modal Analysis, Spectral Feature, Texture, Vibrational Processes.
User
Notifications
Font Size

  • Hunt, G. R. and Salisbury, J. W., Visible and near-infrared spectra of minerals and rocks: II. Carbonates. Mod. Geol., 1971, 2, 23–30.

  • Clark, R. N. and Roush, T. L., Reflectance spectroscopy quantitative analysis techniques for remote sensing applications. J. Geo-phys. Res., 1984, 89(B7), 6329–6340.

  • Clark, R. N., Spectroscopy of rocks and minerals, and principles of spectroscopy. USGS spectral laboratory; http://speclab.cr.usgs.gov/spectral-lib.html (accessed 7 December 2011).

  • Clark, R. N., King, T. V. V., Klejwa, M. and Swaze, G. A., High spectral resolution reflectance spectroscopy of minerals. J. Geo-phys. Res., 1990, 95(B8), 12653–12680.

  • Cloutis, E. A., Hyperspectral geological remote sensing: evaluation of analytical techniques. Int. J. Remote Sensing, 1996, 17(12), 2215–2242.

  • Clark, R. N., Swayze, G. A., Heidebrecht, K., Green, R. O. and Goetz, A. F. H., Calibration to surface reflectance of terrestrial imaging spectrometry data: comparison of methods, summaries of the fifth annual JPL airborne geosciences workshop. Jet Propulsion Laboratory Special Publication, 1995, pp. 41–42.

  • Guha, A., Chakraborty, D., Ekka, A. B., Pramanik, K. and Chatterjee, S., Spectroscopic study of rocks of Hutti-Maski Schist Belt, Karnataka. J. Geol. Soc. India, 2012, 79, 335–344.

  • Guha, A., Rao, A., Ravi, S., Vinod Kumar, K. and Dhananjaya Rao, E. N., Analysis of the potentials of kimberlite rock spectra as spectral end member – a case study using kimberlite rock spectra from the Narayanpet kimberlite Field (NKF), Andhra Pradesh. Curr. Sci., 2012, 103(9), 1096–1104.

  • Carli, C. and Sgavetti, M., Spectral characteristics of rocks: effects of composition and texture and implications for the interpretation of planet surface compositions. Icarus, 2011, 211(2), 1034–1048.

  • Dennis, K. M., Spectral properties (0.4 to 25 microns) of selected rocks associated with disseminated gold and silver deposits in Nevada and Idaho. J. Geophys. Res.: Solid Earth, 1986, 91(B1), 2156–2202.

  • Guha, A., Vinod Kumar, K., Ravi, S. and Dhanamjaya Rao, S., Reflectance spectroscopy of kimberlites – in parts of Dharwar Craton, India. Arabian J. Geosci., 2015, 8(11), 9373–9388.

  • Khan, S. D. and Mahmood, K., The application of remote sensing techniques to the study of ophiolites. Earth Sci. Rev., 2008, 89, 135–143.

  • Khan, S. D., Mahmood, K. and Casey, J. F., Mapping of Muslim Bagh ophiolite complex (Pakistan) using new remote sensing and field data. J. Asian Earth Sci., 2007, 30, 333–343.

  • Pournamdari, M., Hashim, M. and Pour, A. B., Spectral transformation of ASTER and Landsat TM bands for lithological mapping of Soghan ophiolite complex, south Iran. Adv. Space Res., 2014, 54, 694–709.

  • Rajendran, S. et al., ASTER detection of chromite bearing mineralized zones in Semail Ophiolite Massifs of the northern Oman Mountains: exploration strategy. Ore Geol. Rev., 2012, 44, 121–135.

  • van der Meer, F., Analysis of spectral absorption features in hyperspectral imagery. Int. J. Appl. Earth Observ. Geoinfor., 2004, 5, 55–68.

  • Tangestani, M. H., Jaffari, L., Vincent, R. K. and Maruthi Sridhar, B. B., Spectral characterization and ASTER-based lithological mapping of an ophiolite complex: a case study from Neyriz ophiolite, SW Iran. Remote Sensing Environ., 2011, 115, 2243–2254.

  • Mukherjee, R., Mondal, S. K., Rosing, M. T. and Frei, R., Compositional variations in the Mesoarchean chromites of the Nuggihalli schist belt, Western Dharwar Craton (India): potential parental melts and implications for tectonic setting. Lithos, 2010, 160, 865–885.

  • ASD, I., Field spec specification, 2012; www.asdi.com.

  • Blom, R. G., Abrams, M. J. and Adams, H. G., Spectral reflectance and discrimination of plutonic rocks in the 0.45–2.45 μm region. J. Geophys. Res., 1980, 85(B5), 2156–2202.

  • Walter, L. S. and Salisbury, J. W., Spectral characterization of igneous rocks in the 8–12 μm region. J. Geophys. Res.-Solid Earth, 1989, 94(B7), 2156–2202.

  • Cloutis, E. A., Sunshine, J. M. and Morris, R. V., Spectral reflectance-compositional properties of spinels and chromites: implications for planetary remote sensing and geothermometry. Meteor. Planet. Sci., 2004, 39(4), 545–565.

  • Mitra, S. and Bidyananda, M., Evaluation of metallogenic potential of the Nuggihalli greenstone belt, South India. C. R. Geosci., 2003, 335(2), 185–192.

  • Ramakrishnan, M., Precambrian mafic magmatism in the western Dharwar craton, Southern India. J. Geol. Soc. India, 2009, 73, 101–116.

  • Radhakrishna, B. P. and Vaidyanathan, R., Geology of Karnataka, Geological Society of India, Bangalore, 1994, p. 298.

  • Devaraju, T. C., Viljoen, R. P., Sawkar, R. H. and Sudhakara, T. L., Mafic and ultramafic magmatism and associated mineralization in the Dharwar craton, southern India. J. Geol. Soc. India, 2009, 73, 73–100.

  • Droop, G. T. R., A general equation for estimating Fe3+ concentrations in ferromagnesian silicates and oxides from microprobe analysis, using stoichiometric criteria. Mineral. Mag., 2011, 51, 431–435.

  • Ghosh, B. and Konar, R., Chromites from metaanorthosites, Sitampundi layered igneous complex, Tamil Nadu, southern India. J. Asian Earth Sci., 2011, 42, 1394–1402.

  • Milton, E. J., Schaepman, M. E., Anderson, K., Kneubahler, M. and Fox, N., Progress in field spectroscopy. Remote Sensing Environ., 2009, 113, S92–S109.

  • Baldridge, A. M., Hook, S. J., Grove, C. I. and Rivera, G., The ASTER spectral library version 2.0. Remote Sensing Environ., 2009, 113, 711–715.

  • Nicodemus, F. F., Richmond, J. C., Hsia, J. J., GIinsberg, I. W. and Limperis, T. L., Geometrical considerations and nomenclature for reflectance In National Bureau of Standards Monograph (ed. Office, D. C. U. S. G.), Washington, 1977, p. 20402.

  • Biggar, S. F., Labed, J., Santer, R. P. and Slater, P. N., Laboratory calibration of field reflectance panels. In Proceedings of SPIE – The International Society for Optical Engineering (ed. Slater, P. N.), Orlando, Florida, 1988, pp. 232–240.

  • Bruegge, C. J., Chrien, N. and Haner, D., A spectralon BRF database for MISR calibration applications. Remote Sensing Environ., 2001, 76, 354–366.

  • Crowley, J. K., Visible and near-infrared spectra of carbonate rocks reflectance variations related to petrographic texture and impurities. J. Geophys. Res., 1986, 91(B5), 5001–5012.

  • Okada, K. and Iwashita, A., Hyper-multispectral image analysis based on waveform characteristics of spectral curve. Adv. Space Res., 1992, 12, 433–442.

  • van der Meer, F. D., Basic physics of spectrometry. In Imaging Spectrometry: Basic Principles and Prospective Applications (eds van der Meer, F. D. and de Jong, S. M.), Springer, Dordrecht, 2006, pp. 3–16.

  • Trude, K. V. V. and Clark, R. N., Spectral characteristics of chlorites and Mg-serpentines using high-resolution reflectance spectroscopy. J. Geophys. Res.: Solid Earth, 1989, B10, 13997–14008.

  • Jafri, S. H., Khan, N., Ahmad, S. M. and Saxena, R., Geology and Geochemistry of Nuggihalli Schist belt, Dharwar craton, Karnataka, India. In Precambrian of South India (eds Naqvi, S. M. and Rogers, J. J. W.), Memoir Geological Society of India, 1983, vol. 4, pp. 110–120.


Abstract Views: 231

PDF Views: 84




  • Spectral Response of Few Important Textural Variants of Chromitite and its Potential in Estimating Relative Grades of Chromitite – A Case Study for Chromitite of Nuggihalli Schist Belt, India

Abstract Views: 231  |  PDF Views: 84

Authors

Arindam Guha
Geosciences Group, National Remote Sensing Centre, Indian Space Research Organization, Balanagar, Hyderabad 500 625, India
Biswajit Ghosh
Department of Geology, University of Calcutta, 35 Ballygunge Circular Road, Kolkata 700 019, India
Sukanya Chaudhury
Department of Geology, University of Calcutta, 35 Ballygunge Circular Road, Kolkata 700 019, India
Komal Rani
Geosciences Group, National Remote Sensing Centre, Indian Space Research Organization, Balanagar, Hyderabad 500 625, India
K. Vinod Kumar
Geosciences Group, National Remote Sensing Centre, Indian Space Research Organization, Balanagar, Hyderabad 500 625, India

Abstract


We have collected, processed and analysed the reflectance spectra of representative chromitite samples of spot type, clot type and disseminated type textural variants to understand the diagnostic spectral features of each of these samples. We have found that the reflectance spectrum of each textural variant is distinct from the spectra of other variants despite having few common absorption features. Spectral features of chromitite samples are governed by the spectra of two dominant minerals, chromite and chlorite. Spectral features of chromitite at 550 nm and 1100 nm are governed by electronic transition process in Fe3+ and crystal field effect in Fe2+ ions present in chromite structure respectively. On the other hand, spectral features at 1400 nm, 1900 nm and 2300 nm are related to the vibration of O–H, H–OH and metal hydroxide bonds in chlorite. Amongst these features, the spectral feature at 1100 nm (due to Fe2+ in chromite grains) is common to all three major textural varieties of chromitite samples studied here. Electron probe micro analysis (EPMA) data of chromite and chlorite grains of each texture are used to relate the presence and abundance of Fe2+ (in chromite grains) with absorption feature. Width of the 1100 nm feature has a correlation value 0.95, while depth of the same feature has a correlation value 0.94 with the abundance of chromite mineral estimated using modal analysis of chromite samples. Therefore, spectrometric parameter of 1100 nm spectral feature of chromitite can be used as proxy for estimating modal abundance of chromite in chromitite samples after estimating deposit specific correlation coefficient.

Keywords


Chromitite, Electronic Processes, Modal Analysis, Spectral Feature, Texture, Vibrational Processes.

References





DOI: https://doi.org/10.18520/cs%2Fv114%2Fi08%2F1721-1731