The magnetic response of hydrothermal alteration in iron-oxide basement complex, NW Nigeria

• Autorzy: Aisabokhae Joseph Ehimare , Bamidele Oresajo

Identyfikatory

DOI

10.7494/geol.2019.45.2.145

• Języki publikacji: EN

Abstrakty

EN

Aeromagnetic data was processed in order to delineate structural trends which may be indicative of potential gold mineral traps in the Watari hill gold prospect located between longitude 5°8''and 5°16'', and latitude 11°24'' and 11°30'' in Garin Hawal district, northwest Nigeria. Landsat-8 OLI data was processed to produce colour composite, band ratio and minimum noise fraction images that mapped the hydrothermal alteration zone in the study area. The multispectral images which were displayed in Red-Green-Blue colours were subsequently pan-sharpened to display a greater image resolution of the area. The application of enhancement algorithms such as an analytic signal to the aeromagnetic data over the alteration zone helped in mapping the mafic metavolcanics, felsic metasediments and intruding granitoid complexes. Further reductions using the second vertical derivative and tilt angle derivative filters aided in delineating fracture/faults and the contact zones of the formations, especially the metasediments-metavolcanic boundary that delineates the shear zone. This study showed that the low-angle geologic structure between the metasediments and metavolcanics where hydrothermal alteration is present is likely to accommodate veins of gold mineralization in the study area.

Słowa kluczowe

EN

alteration mapping; remote sensing; shear zone; aeromagnetic data

• Wydawca: Wydawnictwa AGH
• Czasopismo: Geology, Geophysics and Environment
• Rocznik: 2019
• Tom: Vol. 45, no. 2
• Strony: 145--156
• Opis fizyczny: Bibliogr. 14 poz., rys., tab., wykr.

Twórcy

autor

Aisabokhae Joseph Ehimare

• Federal University Birnin Kebbi, Department of Applied Geophysics; Nigeria

autor

Bamidele Oresajo

• Federal University Birnin Kebbi, Department of Geology; Nigeria

Bibliografia

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Uwagi

PL

Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2019).