Validation Approach of the Tectonic Lineament Extraction Enhancement Using Sentinel 2A Images and Modified 3 &#215; 3 Bidirectional Prewitt Filters. Case Study: Grombalia, Tunisia

Mansouri Karim,Noamen Rebai,Sonya Gannouni,Imed Riadh Farah,Slimene Sedrette

doi:10.4236/jgis.2021.136037

Validation Approach of the Tectonic Lineament Extraction Enhancement Using Sentinel 2A Images and Modified 3 × 3 Bidirectional Prewitt Filters. Case Study: Grombalia, Tunisia

Mansouri Karim, Noamen Rebai + Show 3 more

Open Access

https://doi.org/10.4236/jgis.2021.136037

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Abstract

In this study, filters are used to extract directional tectonic lineaments and, thus, to reveal the presence of faults or fractures in the satellite images. The extraction process consists first in eliminating other different types of lineaments (e.g. the lithological limit, ridgelines, hydrographic network, roads, etc.). Besides, a comparative and quantitative approach is applied to show that when the directional Prewitt filter has a zero setting of the opposite of the assumed direction, as is the case of the N-S direction, the East-West direction is also set to zero. This research work, based on a bidirectional filter (N-S; E-W), shows satisfactory results especially concerning the quantitative fluctuation of lineament directions by interval. This fluctuation is in perfect agreement with the lineaments provided by the digitizing of the different tectonic accidents directions extracted in a GIS environment from the geological map of Grombalia. In this research work, a quantitative approach was used to evaluate the result of the lineament extraction methodology based on one direction analysis and by an interval of directions. Indeed, the N45 lineament direction, well documented in the geological study of the region, was more clearly distinguished by applying the Prewitt filter than by using the Sobel filter. The result was validated by comparison with the results obtained by the digitization of the tectonic accidents mapped on the geological map.

Highlights

Tectonic lineament mapping facilitates the location of the appropriate site for mineral exploration [1] [2] [3]
This fluctuation is in perfect agreement with the lineaments provided by the digitizing of the different tectonic accidents directions extracted in a GIS environment from the geological map of Grombalia
The result of the automatic lineament extraction (Table 10) shows that the number of lineaments in the same range is 1137 among 4786 lineaments extracted from the 3 × 3 filters; 2179 among 9745 lineaments extracted from 5 × 5 filters; and 2,700 of the 13,000 lineaments extracted from the 7 × 7 filters, representing a percentage of 23.76%, 22.36% and 20.77%, respectively

Summary

Introduction

Tectonic lineament mapping facilitates the location of the appropriate site for mineral exploration [1] [2] [3]. It is very effective in mineral prospection. This technique allows orienting prospection during the reconnaissance phase. Many recent works ([4] [5] [6]) have shown that these fractures originated groundwater formation in fissured basement environments and constitute the ultimate zones of water flow. The investigation of this faults network during dam construction remains essential. The main objective of this study is to improve the process of tectonic accidents lineaments extraction from optical satellite images, this extraction could be carried out from other data sources (e.g. geomorphology and morphometric indices) as well as from other types of sensors (e.g. radar images) [7] [8]

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