Role of REMOTE SENSING applications in MINERAL exploration and - PowerPoint PPT Presentation

Role of REMOTE SENSING applications in MINERAL exploration and sustainable development in OMAN Rajendran Sankaran* and Sobhi Nasir** * Department of Earth Sciences, Sultan Qaboos University, Oman ** Earth Science Research Centre, Sultan Qaboos University, Oman. E-mail: rajendra@squ.edu.om

Spectra of minerals:

Remote Sensing capability to map minerals • Hyperspectral images can be analyzed in ways that multispectral images cannot

ASTER spectral bands Absorptions Figure Shows the spectral absorptions of major minerals rocks stacked from the USGS Spectral Library for minerals (Rajendran and Nasir, 2015).

Economic Mineral Resources of the Sultanate of Oman (Ministry of Commerce and Industry, Oman. 2012). Fig. 1. Minerals occurrence map of the Sultanate of Oman

Significance: Satellite data and Mapping of minerals of the Sultanate of Oman • Applications of remotely sensed satellite data are wide and unique in mapping of different lithologies, mineral resources and ore deposits. • Oman has potential occurrence of the industrial minerals and ore deposits which are mostly occurred in inaccessible mountains and deserts regions where it is difficult to do conventional geological mapping. • The technique is low-cost and save time in mapping and exploration of such resources and well suitable and applicable to Oman and arid region.

Spectral bands Absorption characters of ASTER and Image processing Methods • This work shows t he absorption characters of spectral bands of Advanced Space borne Thermal Emission and Reflection Radiometer (ASTER) and • Selected imaging processing methods namely decorrelation stretching, band ratios, linear spectral unmixing (LSU) and Mixture Tuned Matched Filtering (MTMF) • To understand the sensor has capability to map several mineral deposits and different rock lithologies in Oman • It includes copper, chromite, awaruite, and manganese deposits, and limestone, listwaenites, carbonatites, metamorphic zones rock formations of different parts of the Sultanate of Oman.

CASE STUY 1: ASTER detection of chromite bearing mineralized zones in Semail Ophiolite Massifs of the northern Oman mountain Rajendran et al. (2012) Ore geology reviews, 44, 121-135.

d. N a. b. 56º15' 56º25' N AL Shinas LEGEND Mq-Maqoum formation Wadi Fizz Dh- Dhera formation Hf- Halfa formation Gulf of Oman Ex- Oman exotics * HD-Hamrat Duru group of formations * * * Wa-Wahrah formations E- Basic extrusive mostly * * 24º 24 * spilites with pillow lava or * * 35' * * º conglomerate * 35' * Hasaifi D- Diabase dyke swarms * * * * * n G- Gabbro * HG-Gabbroid hypabyssal * rocks PG-Cumulate layered gabbro * * Cr P - Sheared serpentinized * harzburgite with minor dunite * * Wadi Fizz * * * * * * * Geology of Oman Mountain (after 24º 24 * 25' * º 25' Scale: 0 5Km Watts, 1990) showing the locations of b. Ophiolite Sequence, c. geology (Source: Al Hinaynah Ministry of Petroleum and Minerals, * Ro’s Sultan * 1987) and d. ASTER RGB (3,2,1) image Sohar of study area c. 56º15' 56º25'

P D G PG D E G P E Landsat TM RGB (7, 5, 4 PG E G bands) decorrelated image of Study area (Abrams et P E al., 1988). The abbreviations of the image D are E- Basic extrusives D CD mostly spilites with pillow lava or conglomerate; D- D Diabase dyke swarms; G- E D Gabbro; HG- Gabbroid PG hypabyssal rocks; PG- P HG Cumulate layered gabbro; P CD and CD- Sheared D E serpentinized harzburgite. HG PG P CD D E CD PG HG P E E P PG

b a D D . . G G P P P D P D G G E E G G P P E E E E G G P P P P E G E G D D D D C C P P D D D D E E D D P P P P G G HG HG C C D E D E D D P P G G C C P D E P D E D C D C P HG HG D D P P P G G E E E E P P C P C P D G D G c . D G ASTER RGB band ratios image a. P P D G E Abdeen et al., 2001 (4/7, 4/1, G P 2/3*4/3) b. (4/7, 3/4, 2/1) and c. E E Amer et al., 2009 ((2+4)/3, G P P (5+7)/6, (7+9)/8) of the study G E area. The abbreviations of the D D image are E- Basic extrusives P D mostly spilites with pillow lava or E D P P conglomerate; D- Diabase dyke G HG swarms; G- Gabbro; HG- D E Gabbroid hypabyssal rocks; PG- P G Cumulate layered gabbro; P and P D E CD- Sheared serpentinized HG P P harzburgite. G E E P P G

P D G PG D E G P E PG E G RGB image of PC7, PC5 and PC4 of PCA bands of the P E study area. The abbreviations of the image are E- Basic D extrusives mostly spilites with D CD pillow lava or conglomerate; D- Diabase dyke swarms; G- D Gabbro; HG- Gabbroid E D hypabyssal rocks; PG- PG Cumulate layered gabbro; P P HG and CD- Sheared serpentinized harzburgite. CD D E HG PG P CD D E CD PG HG P E E P PG

CASE STUY 2: Characterization of ASTER spectral bands for mapping of alteration zones of volcanogenic massive sulphide deposits Rajendran and Nasir (2017) reviewed paper submitted to Ore geology reviews.

Geology of study area shows the occurrence of Cu, Au and Ag mainly in the lower extrusive ( Ministry of Petroleum and Minerals, 1987)

RGB image of ASTER band ratios (5/3+1/2), (4+6)/5 and (5+7)/6 shows the mineralized zones (spotted Cu occurrences) of the study area (Image is linear stretched with Red: 1.1 to 1.3; Green: 3.6 to 4.3; Blue: 1.8 to 2.0).

RGB image of ASTER indices (R: OH bearing altered minerals, G: kaolinite B: alunite minerals indices) shows the occurrence and spatial distribution of altered minerals in the study area (Red square is an area chosen for detailed study; the image is linear stretched with Red: 2.5 to 3.1; Green: 1.6 to 2.0; Blue: 1.0 to 1.4).

(a) ASTER RGB (3, 2, 1) image shows the occurrence of gossan (yellow squared, the area in Fig. 16) and old mine, and (b) the distribution of pixels of the oxidised (red), propylitic (green), argillaceous (cyan) and phyllic (pink) zones derived based on SAM endmembers (1, 3, 5 and 7) over MNF image (band 2) of the gossanized area.

CASE STUY 3: Mapping of manganese potential lithology in parts of the Sultanate of Oman Rajendran and Nasir (2017) International Journal of Geosciences and Geomatics 1(2), 92-101.

59  35’E 59  40’E 59  45’E E se N J gw EO sa Geology of study region occurred near Ras Al Hadd of Al- Batain basin of NE Qcy-z Oman margin 22  25’N 22  25’N (Ministry of Petroleum and Minerals 1993). Q ed 22  30’N 22  20’N Q es Q by-z 59  35’E 59  40’E 59  45’E 0 4km

Rhodochrosite HS338.3B Manganite HS 138.3B Pyrolusite O-6A Psilomelane HS 139.3B Image spectra of 14 ASTER spectral bands Spectral plot of manganese minerals stacked shows diagnostic absorption of manganese in from USGS and JPL spectral libraries. VNIR and SWIR regions (1-9 spectral bands, low Pyrolusite (MnO 2 ), Psilomelane ((Ba, H 2 O) 2 reflectance) and strong emission in TIR region Mn 5 O 10 ), Manganite (MnO(OH)) and (10-14 spectral bands). Rhodochrosite (MnCO 3 )

Ese Ese Sea water LEGEND JK wa c Q cy-z Q ty Q ty Q cy-z intrusions EO sa Q ty JK wa c Q ty JK wa c Q by-z Q ty J gw Q cy-z Post – Nappe Units JK wa c J gw Q cy-z J gw Quaternary Formations J gw J gw Q ty Q fy Q ty Q cy-z -Sub-recent alluvial fans and terraces Q ty J gw Q tx Q ty Jm b 2 Q tx JK wa c Q tx -Ancient alluvial terraces JK wa c Q ty JK wa c Q ty TR sm - Sabkhah deposits TR sm Q ty J gw Q by-z Mn Q ty JK wa c JK wa c J gw Q ty Q tx Q cy-z - Slope colluviums and collapse structure JK wa c J gw JK wa c Q tx JK wa c - Aeolian sand veneer Q ty Q es Q ty Q ty J gw Q tx -Low active sand dunes, meso-ridges Q ed Q ty JK wa c JK wa c J gw Q tx Q ty Tertiary Formations Q ty JK wa c Q cy-z JK wa c JK wa c - Dhofar Group: Shama Formation JK wa c Bioclastic marl limestone, bioclastic Q tx EO sa limestone and dolomite Q ty TR sm Q ty - Upper Hadhramaut Group: Seeb JK wa c Ese JK wa c JK wa c Formation- Bioclastic limestone, Q ty Q ty JK wa c calcarenite and marl subordinate sandstone b P TRa j Q tx Q ty Hawasina Nappes Q ty Q tx Q ty JK wa c TR sm Q ty Al Aridh Group: Sayfam Formations Q ty TR sm - Megabreccia, calcirudite, radiolarian chert, micritic JK wa c JK wa c Q ty TR sm limestone with pelagic bivalves. TR sm v Q tx - Basaltic andesite JK wa c Q ty Hamrat Duru Group JK wa c Q ty Wahrah Formation: JK wa c TR sm v JK wa c JK wa c JK wa c - Red and white Radiolarian chert, shale, calcarenite JK wa c JK wa c Q ty JK wa c Q ty Guwayza Formation: JK wa c TR sm J gw TR sm - Oolitic calcarenite, calcirudite J gw JK wa c JK wa c TR sm TR sm Q ty Matbat Formations: Q tx b JK wa c P TRa j - Turbiditic quartz sandstone, calcarenite, shale. J mb2 Q ty Q tx - Radiolarian chert, calcarenite, micritic Q fy Q ty Q by-z J gw limestone with pelagic bivalves TRm b 1 Q fy Q ed Pa j v Q fy P TRa j b J gw TR sm Al Jil Formations: Q es Q tx - Calcirudite and Permian carbonate as boulders and P TRa j b megabreccia Q es Q fy - Basaltic pillow lava, andesite Q ty Pa j v TRm b 1  Mn (Manganese) Q ty JK wa c Q fy Q tx Arrows area zoomed Q fy Q fy Q fy ASTER RGB image of band ratio (1+3)/2, (3+5)/4 and (5+7)6 of study region.