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Geospatial Technology-Based Artificial Groundwater Recharge Site Selection for Sustainable Water Resource Management
Published in Satya Prakash Maurya, Akhilesh Kumar Yadav, Ramesh Singh, Modeling and Simulation of Environmental Systems, 2023
Jaysukh Chhaganbhai Songara, Jayantilal Naginbhai Patel
The development of groundwater relies upon the geographical setting. A visual interpretation of the satellite picture has been utilized for an outline of land highlights. Figure 17.3(a) shows geographical investigation territory has been characterized into five classes: Flood Plains, Pediplain, Plateau, Educational Hills, and Structural Hills. Pediplain yields a good quantity of groundwater; the Pediment area gives moderately good amount of groundwater. The location of the highly dissected Plateau, denudation hill, and the lateritic Plateau were poor for groundwater prospecting (Terêncio et al., 2017).
Morphologic evolutionary systems
Published in Richard J. Chorley, Stanley A. Schumm, David E. Sugden, Geomorphology, 2019
Richard J. Chorley, Stanley A. Schumm, David E. Sugden
The concept of large-scale pediplanation was developed by L .C. King more than thirty years ago to account for extensive surfaces of low relief in Africa and the tropics, as well as for uplifted surface remnants in higher latitudes (Figure 2.8D). Pediplanation was conceived as dominated by slow parallel scarp retreat under arid, semi-arid and savanna (seasonal wet-dry) climates leaving in its wake broadly concave surfaces (<6°–7°), often studded with steep-sided residual hills (inselbergs), varying in size depending on their degree of erosive consumption (e.g. mesas and buttes) and in shape depending on underlying rock structure. Thus angular slope profiles and residuals are associated with horizontal sedimentary rocks or with surfaces capped by material cemented by some processes of chemical weathering (i.e. duricrusts, including silcretes and calcretes (caliche)), whereas rounded profiles and residuals (bornhardts) are supported by curved weathering or pressure-release jointing, notably in granites (Plate 27). Once formed, the low-angle pediplain surfaces are subject to only minute erosion and are capable of persisting for very long periods until they are themselves consumed by a new sequence of steep slope (15°–30°) retreat initiated by isostatic uplift on a regional scale, perhaps in response to metamorphic changes of geochemical origin in the subcrust. In this way one phase of pediplanation may be succeeded by uplift, marginal canyon-cutting and extension, leading to a wave of scarp retreat sweeping across country for long distances, and leaving inselbergs of up to 300 m (1000 ft) in its wake, until their reduction blurs them into the generally concave pediplain surface. Particularly where formed in resistant rocks, pediplains and pediplain remnants are believed to achieve great antiquity, so much so that the highest pediplain remnants are believed by King to have formed before the break-up of the southern hemisphere continental plates in the Jurassic (see Figure 2.10). Late Tertiary uplift initiated a new phase of pediplanation in Southern Africa, leading to a model of its continental surface as a giant staircase of mutually consuming steps. Despite the existence of these extensive surfaces of low relief separated by clifflike escarpments in the tropics, the concept of antique pediplanations must remain questionable, if only because of the vast periods of time involved and our lack of knowledge regarding the nature and rapidity of erosional processes in subhumid environments.
Forecasting landslides using SIGMA model: a case study from Idukki, India
Published in Geomatics, Natural Hazards and Risk, 2021
Minu Treesa Abraham, Neelima Satyam, Nakshatram Shreyas, Biswajeet Pradhan, Samuele Segoni, Khairul Nizam Abdul Maulud, Abdullah M. Alamri
The reference area for the first rain gauge, R1 represents the midland region of Idukki with nearly flat terrain, R2 and R3 represents the hilly area in the eastern side centre respectively and R4 consists of the peaks and foothills near the mountains in the northern side. The midland area of Idukki (R1) has a rugged topography, with a slope towards west. R1 is composed of pediment-pediplain complex of denudational origin. The hilly terrains can be divided into high ranges, plateau and foothills. The plateau region (R3 and parts of R2) covers maximum area and is the chief physiographic unit of Idukki. The elevation of this region varies from 500 m to 1500 m above sea level with a slope of around 30%. A major part of the district is formed by the hill ranges (R2 and R4) of Western Ghats. The slope of this region is between 30% and 50% and occasionally goes upto 80%. The peaks above 1500 m are characterized as high ranges (R4). R4 is the steepest zone with several peaks, composed of low dissected hills and valleys. The region is famous for its tea plantations and the hills have undergone several cutting and filling activities for infrastructure development, in the recent past. R2 region is formed by highly dissected hills and valleys.
Effect of spatial resolution and data splitting on landslide susceptibility mapping using different machine learning algorithms
Published in Geomatics, Natural Hazards and Risk, 2021
Minu Treesa Abraham, Neelima Satyam, Prashita Jain, Biswajeet Pradhan, Abdullah Alamri
The geology and geomorphology layers are vector files published by GSI. Both the layers are highly significant in the initiation of landslides as the physical processes of landslide triggering are related to the rock type and morphology. Geology explains the bedrock type, while geomorphology explains the interaction of rock with the environment (Youssef et al. 2015). The geology of the region is classified into six categories, viz charnockite group, khondalite group, migmatite complex, peninsular gneissic complex, acid intrusive and basic intrusive (Geological Survey of India 2010). Similarly, there are five prominent categories in geomorphology, i.e., highly dissected hills and valleys, moderately dissected hills and valleys, low dissected hills and valleys, anthropologic terrains and pediment and pediplain complex. From the landslide inventory data, it was observed that more than 70% of the landslides have occurred on terrain which is composed of the migmatite complex and peninsular gneissic complex. These regions are geomorphologically classified as highly and moderately dissected hills and valleys. The vector files were rasterized into two different resolutions, according to the DEM, for a comparative study.