Drought Risk Assessment in the Khushab Region of Pakistan Using Satellite Remote Sensing and Geospatial Methods

Drought is a harmful and slow natural phenomenon that has significant effects on the economy, social life,agriculture and environment of the country. Due to its slow process it is difficult to study this phenomenon. RemoteSensing and GIS tools play a key role in studying different hazards like droughts. The main objective of the study wasto investigate drought risk by using GIS and Remote Sensing techniques in district Khushab, Pakistan. Landsat ETMimages for the year 2003, 2009 and 2015 were utilized for spatial and temporal analysis of agricultural andmeteorological drought. Normalized difference vegetation index (NDVI) Standardized Precipitation Index (SPI) andrainfall anomaly indices were calculated to identify the drought prone areas in the study area. To monitormeteorological drought SPI values were used and NDVI was calculated for agricultural drought. These indices wereintegrated to compute the spatial and temporal drought maps. Three zones; no drought, slight drought and moderatedrought were identified. Final drought map shows that 30.21% of the area faces moderate drought, 28.36% faces slightdrought while nearly 41.3% faces no drought situation. Drought prevalence and severity is present more in the southernpart of Khushab district than the northern part. Most of the northern part is not under any type of drought. Thus, anoverall outcome of this study shows that risk areas can be assessed appropriately by integration of various data sourcesand thereby management plans can be prepared to deal with the hazard

Neotectonics of Zindapir Anticline and Sulaiman Fold and Thrust Belt: Inferences from SRTM DEM

The current study deals with the significance of surface dynamics (SDs) and its relationship to tectonics and active erosion in Zindapir Anticline (ZPA) and neighboring Sulaiman Fold and Thrust Belt (SFTB) which is a direct result of transform plate movement between Indo-Pak continent and Eurasia. The Shuttle Radar Topographic Mission Digital Elevation Model SRTM DEM with 30 m resolution was employed to compute SDs; Isobase (IBL), drainage density (DD), relative relief (RR) and vertical dissection (VD) thematic maps for the study area. The results obtained show that the DD, RR, VD and IBL have higher values in north west, central segments and south west of the SFTB, whereas the Zindapir anticline represents dextral movement on its east side while sinistral sense of movement is observed on its western edge. High values of RR and VD correspond to highly incised topography with great surface roughness. The enhanced values of IBL and DD in the northwest, south west and central SFTB correspond to uplifted active topography segments and can trigger medium level earthquakes in this region. The conjugate movement of ZPA is an indication of its neotectonic nature and recent uplift is causing surface deformation which needs to be understood in the context of SFTB development as a result of India-Eurasia transform movemen

Comparative Analysis of Different Remote Sensing Techniques for Mapping of Supraglacial Lakes on Hispar Glacier

The glacier changes are very significant in quantifying the direct effects of climate change. The glaciers inthe northern Pakistan especially in the Karakoram pose a large change in relief and are difficult to access due tocomplex topography. The global WOS (Web of Science) database indicate only a few studies conducted so far in thisregion in the domain of climate and cryosphere. The studies relating to glacial hazards in this region are even less. Thisstudy involves the mapping of supraglacial lakes on Hispar glacier using multiple remote sensing methods. Theaccuracy of results from those methods is discussed. Remote Sensing and GIS techniques have been applied to timeseries of Landsat images of years 2017, 2016, 2010, 2000 and 1990 (in the descending order) to quantify thesupraglacial lakes on the Hispar glacier. The remote sensing techniques include Band Rationing, Normalized WaterIndex (NDWI), Classification i.e. Unsupervised and Panchromatic Sharpening Image Enhancement Technique for theyears of 2017 and 2016 imageries. After defining the Hunza basin (involving of high resolution DEMs), all the satellitederived imageries have been preprocessed and processed. GIS tools have been used to calculate the areal extents ofyearly obtained supraglacial lakes and compare temporally with passing years, which in turn gave an accuratecomparative analysis among different remote sensing techniques. The satellite derived time series map layouts of eachtechnique have been formulated. The vulnerable supraglacial lakes on Hispar glacier of areal sizes ≤ 0.05 sq.km havealso been identified and delineate

Evaluation of Fractal Dimension and Topographic Surface Roughness (Vertical Dissection) in Astore-Deosai-Skardu Region in GIS Environment Using ASTER GDEM

Fractal investigation is a valuable technique to model and quantify the composite patterns of natural similarobjects. This study investigates Neotectonics using ASTER-GDEM. Fractal technique for extraction of topographicfractal dimension (Dtopo) and vertical dissection (Rtopo-surf) were used to assess the Neotectonics deformation.Geomorphological regions can be demarcated by using above mentioned procedures as they reveal the topographicevolutionary stages as an evaluation of topographic textures. The idea is to recognize the zones that are stronglyinfluenced by Neotectonics. Astore-Deosai-Skardu (ADS) region in Gilgit-Baltistan was selected for this purpose as itlies between MKT and MMT which is experiencing surface topographic deformation (STD) caused by anti-clock-wiseprogression and subduction of Indian plate beneath Eurasia. The results obtained illustrates that Dtopo and Rtopo-surf showanomalies in the ADS region that clearly represent a robust control of nearby MMT, MKT and KkF and highlights theirsignificance to describe regions vulnerable to Neotectonics and related deadly events threatening precious human livesand infrastructure damages

A Study of Active Chaman Fault System (CFS) using SRTM DEM

Chaman fault is a seismically active fault running over 850km in western region of Pakistan and Afghanistan. It is a major geological structure between Indian and Eurasian plates. Chaman fault is a strike slip fault which is slipping nearly at the rate of 10mm per year. This research includes the evaluation of lithological processes and neotectonics activity using Hypsometric Integral (HI). We calculated values of hypsometric integral using SRTM DEM with 90m spatial resolution in active region of Chaman Fault (CF) and in its locality. We analyzed different mean, minimum and maximum elevations using regular square grids and measured the degree of spatial distribution of HI using Local Indices (LI) of Spatial Autocorrelation (LISA). LISA provides auto correlation for the cluster analysis of hotspots and cold spots of HI values to discriminate uplifted and eroded regions. Full Tex

Remote Sensing Evaluation of Neotectonics in Potwar Plateau Lesser Himalyas Pakistan

The Potwar plateau was developed in subduction zone of lower Himalayan fold and thrust in the North West region. This study identifies topographic deformation and neotectonics activity using Digital Evaluation Model (DEM). The SRTM DEM having resolution of 90 m analyzes active tectonics in local drainage network. Standard algorithms and geomorphic indices are used to extract isobase maps, concavity, steepness and relative rates of uplift. The steepness index indicates the elevation of Potwar region. The variable rates of uplift, indicates surface deformation in different regions of Potwar plateau. Isobase maps indicate lithological distinctions and structures under the influence of neotectonics using geological maps. Landsat satellite imagery was used to indicate neotectonics activity over the spatial drainage network and streams corresponding to the longitudinal river profile analysis