TELERILEVAMENTO E FOTOINTERPRETAZIONE
Learning outcomes of the course unit
To provide tools for geologic interpretation and mapping by integrated spectroscopic and stereoscopic remote sensing. The tools are: 1) spectroscopic analysis of minerals and rocks, both in the laboratory and RS hyperspectral images for mineralogical analysis of the Earth and extraterrestrial planets surfaces; 2) 3D image analysis to interpret post depositional tectonic structures and stratigraphic sequences both in “passive” geodynamic areas and syntectonic basins. The activity results are compositional and photogeologic maps preliminary to the subsequent field work.
Advanced geologic, petrographic and mineralogical knowledge
Course contents summary
1) Reflectance spectroscopy of minerals and rocks; 2) analysis of remotely sensed hyperspectral images for interpretation and mapping of the surface composition; 3) 3D image interpretation to delineate and mapping tectonic structures and stratigraphic sequences.
1) Remote sensing reflectance spectroscopy for analysis of mineral and rock compositions
1.1) fundamentals of reflectance spectroscopy: optical processes, electronic and vibrational interactions; sensors and methods of data acquisition; multi- and hyperspectral data processing;
1.2) absorption feature variability; 1.2.1) in minerals: position, intensity and width variation in electronic and vibrational bands; 1.2.2) in pure mineral powder mixtures: surface and volume scatterings, grain size effects; 1.2.3) in rocks: textural and composition effects, effects of Fe,Mg mineral mode and chemistry, presence of opaques, amorphous minerals, alteration minerals;
1.3) analysis of absorption bands: parameterization, deconvoluizione;
1.4) Laboratory 1 : analysis of lab spectra of minerals, mineral mixtures, siliceous and carbonate rocks (software: ORIGIN, MGM, EGO);
1.5) data structure: image structure, pixel structure, calibration, correction of the atmospheric effects;
1.6) methods of analysis and classification of hyperspectral images
1.7) Laboratory 2: AVIRIS e MIVIS image analyses (software: ENVI)
2) 3D remote sensing for structural and stratigraphic analyses
2.1) Principles of analogic photogammetric survey: photo frame geometry (central projection; scale, projection axis orientation, object geometry), geometry of the stereogram; stereoscopic survey: analogic cameras; aerial coverage, flight corrections: stereoscopic model: geometric stereo model, optical model, model orientation;
2.2) digital survey: survey geometry; technical characteristics; scale concept for digital images;
2.3) the sensors
2.3.1) photographic sensors: characteristic curve, resolving power, image resolution, spectral characteristics;
2.3.2) electro-optical sensors: CCD, radiometric sensibility, spectral sensitivity, rsolution
2.4) analysis and interpretation of 3D images:
2.4.1) analysis of physical parameters (ddefinition, characteristics, origin, methods of analysis, significance) : tone and texture, erosional profile of strata and strata surfaces;
2.4.2) definition of photostratigraphic units, reconstruction of post-depositional tectonic structures (discussion of selected examples), stereoscopic and spectroscopic data integration,
2.5) Laboratory 3: analysis of syntectonic stratigraphic sequences: analogy between photostratigraphy, physical- and seismic-stratigraphy; photohorizon concept, recognition of photostratigraphic unconformity surfaces e relative chronostratigraphic significance; photofacies concept and significance; delineation of photostratigraphic units in syntectonic basins.
2.6) Laboratory 4: aerial photo analysis of geologically complex areas, photohorizon delineation, compilation of photogeologic maps with phtostratigraphic logs and sections.
Siegal, B.S., and Gillespie, A.R., Remote sensing in Geology. John Wiley & Sons Inc., New York, 1980; Lillesand, T.M., and Kiefer, R.W., Remote sensing and image interpretation. John Wiley & Sons Inc., New York, 1979; Pieters, C.M., and Englert, P.A., Remote geochemical analysis: elemental and mineralogical composition. Cambridge University Press, 1993; Sgavetti, M., Note del Corso 2012-2013.
Lectures, individual exercises, individual laboratory and training
Assessment methods and criteria
evaluation through reports about the work accomplished during exercices and laboratories, e final oral exam