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- Regional geology and tectonic setting
Directional FilteringOne of the treatments used is directional filtering, which consists of image enhancement. The aim of using directional filters is to reveal the linear characteristics to reduce blurring and smooth the image (Abdelouhed et al., 2021). In geological applications, these filters reveal near-bottom fractures with a wide spatial wavelength range from 10 to 100 meters (Farah et al., 2022). The 3*3 matrix was used as a directional filter to determine the order in which the structures should be created. The directional filter was applied in four different orientations (N0°, N45°, N90° and N315°) to the PCA1 (Figure 6) and the panchromatic band 8. ShadingAnalytical hill shading is a method for creating shaded topographic images of the elevations of the earth's surface. It replicates the reflection of artificial light coming from a point source of illumination at a certain elevation (inclination) and azimuth (declination) (Masoud and Koike, 2006). The shading was applied to the SRTM covering our study region. The angles N0°, N45°, N90° and N315° are then selected. Lineaments can be seen between shaded and unshaded regions (Algouti et al., 2022; Masoud and Koike, 2006). Figure (2.9): The flow chart of the landsat8 OLI processing. Chapter Three Regional geology and tectonic settingThe Neotethyan triple junction formed when the Gondwana continent experienced a thermal bulge (plume) caused by hot spots (Chauvet et al., 2009; Langbein et al., 2005; Saccani et al., 2013). This plume rose through the mantle's upper and lower levels. This lithosphere thinned and swelled due to underplating beneath the Gondwana lithosphere. Three arms of the Neo-Tethys Basin formed at the commencement of three radial fractures (Chauvet et al., 2009; Langbein et al., 2005). The union of these three arms produced the Neo-Tethys triple junction. Normal faulting near the southeast of the Arabian plate extension into the continental lithosphere caused the triple junction to form. Neo-Tethys' rifting time is given as early Permian in numerous sources. The two blocks of Central Iran and Arabian Plates formed a stable shield from the Pre-Cambrian to the Late Ordovician (Figure 3.1). This shield separated into two portions during the Early Silurian (Caledonian Orogeny): Central Iran and the Arabian Plates. The absence of Ordovician and Silurian to Carboniferous strata along the Central Zagros, as well as the presence of terrigenous sediments (Sare-Chahan and Zakeen Formations) in the Zagros Crush Zone, indicate that the Neo-Tethys plume was emplaced beneath the Gondwana lithosphere at this time, resulting in epeirogeny between Central Iran and the Arabian plates. The Zagros belt formed as the new Tethys Ocean closed between the Arabian margin and the Eurasian continent. Arabian and Iranian plates appeared before the late Eocene (Berberian and King, 1981). The border region between Iraq and Iran is classified as having converging plate boundaries, representing the collision area between the Arabia-Eurasia plates (Morteza and James, 2004). Convergence between the subduction African plate and the Aegean plate occurs at a rate of 35 mm per year (McClusky et al., 2000). The Arabia-Eurasia convergence acquired an N-S tectonic fabric during the extended Pan-African collision orogenesis. When the pull-apart basins were opened, the heavy salt deposits at Hormuz Fm were deposited in the upper Precambrian-lower Cambrian (Berberian and King, 1981). During the Palaeozoic era, shallow marine sediments covered the Zagros, central Iran, Alborz, and Turkey (Berberian and King, 1981; Ricou, 1994). Arabia moves northeast due to the magma eruption along the Red Sea fault, which is spreading annually at a rate of about 15 mm. Download 0.84 Mb. Share with your friends:
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