KS Sajinkumar

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Verified

KS verified their affiliation via an institutional email.

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• PhD
• Professor (Assistant) at University of Kerala

On the morning of July 30, 2024, a catastrophic landslide struck Wayanad, India, in the ecologically sensitive Western Ghats, claiming over 260 lives, with many still missing beneath the debris. Here, we present a comprehensive overview of the landslide event based on field, satellite, and aerial images analysis, numerical mod-eling, and geotechnic...

Mass wasting events, such as channelized debris flows, can result in heavy sediment fluxes in river systems. On July 30, 2024, a catastrophic debris flow in Wayanad, India, resulted in over 252 fatalities, and deposited approximately 5 million m³ of sediments into the Chaliyar River Valley. We measured sediment fluxes in Chaliyar before, during, an...

26 On the morning of July 30, 2024, a catastrophic landslide struck Wayanad, India, in the 27 ecologically sensitive Western Ghats, claiming over 200 lives, with many still missing 28 beneath the debris. Here, we present a comprehensive overview of the landslide event 29 based on field, satellite images analysis, numerical modeling, geotechnical te...

The Heifangtai loess terrace in Gansu Province (China) suffered from frequent irrigation-induced landslides. In the past 50 years, the perennial channel irrigation has resulted in 210 slope failures within a small area of 9 km2. The landslide activity is particularly linked with the cultivation of vegetables, which need more frequent channel irriga...

In recent years, anthropogenic activities, particularly road-cutting and infrastructure development in fragile topographic settings, have intensified, resulting in an increased number of landslide hazards in hilly terrains. While much attention has been given to the spatial distribution and hydro-meteorological controls of landslides, quantitative...

Chromite is a significant mineral within the spinel group, functioning as a petrogenetic indicator and an important resource for numerous industrial uses. This study investigates the chromite occurrence of the Nuggihalli Schist Belt (NSB), which belongs to the Archean supracrustal greenstone belts of Western Dharwar Craton (WDC), southern India, th...

Luna is a potential impact crater located in the Banni Plains of the Kutch Basin in western India. The suspected impactites, collected from a 1‐m deep trench near the vicinity of the Luna structure, possess a range of physical (porosity and magnetism) properties. Petrographic studies reveal that these impactites are dominated by wüstite, kirschstei...

Investigating the preferential flow path of a debris flow is crucial for quantifying the risk and developing mitigation strategies. Here, we examined 66 debris flows from the Western Ghats in India employing Rapid Mass Movement Simulation (RAMMS)::Debris Flow software to understand the kinematics of run-out. Our analysis revealed that the debris fl...

The long run-out debris flows caused by oversaturated soil systems during the aggravated monsoon period in the Western Ghats raise questions about the hill community’s future. Here, we report the catastrophic long run-out Wayanad debris flow that occurred on 30 th July 2024, which resulted in 231 fatalities and 128 people missing, and caused widesp...

Here, we introduce a new estimate on the areal extent and volume of globally dispersed Youngest Toba Tuff ash by considering the decay of grain size and primary ash thickness (PAT). The areal extent of ash dispersal is modelled by interpolating the farthest sites in four directions. For this modelling, it is assumed that (i) PAT at the farthest new...

Chromite mineralization within Archean greenstone belts is of considerable economic significance; however, the exploration of these deposits in remote and rugged terrains presents substantial challenges. This study evaluates the remote sensing techniques using multispectral satellite data from ASTER, Sentinel-2A, and Landsat 8 to enhance chromite m...

High-pressure mineral phases in the melt rock from the Luna Crater, Gujarat, India ❑ Impact cratering is a key process in the solar system, shaping the origin, and evolution of planets. ❑ Impact cratering played an important role in the history of the terrestrial planets, i.e. (a) Formation of the Moon (giant hypothesis) (b) The Initiation of plate...

The Youngest Toba Tuff (YTT) supervolcanic eruption occurred 75000 years ago, and resulted in distinctive ash fall deposition in different locations encompassing marine, estuarine, lacustrine, and fluvial sedimentary basins. Of the different sedimentary basins, the YTT crypto‐tephra horizon preserved in the South Kerala Sedimentary Basin (SKSB) of...

Landslide susceptibility maps serve as the basis for hazard and risk assessment, as well as risk-informed land use planning at various spatial scales. Researchers create these maps aiming to fulfil a variety of purposes, including infrastructure planning and restrictive land use zoning. These applications require accurate and specific information t...

A quintessential component of any type of landslide studies, like susceptibility mapping, risk assessment and identifying the role of influencing parameters, is a landslide inventory map (LIM). LIM helps to analyse the spatial and temporal characteristics of landslides, and is also vital for constructing a landslide early warning system. Thus, LIM...

We developed a rainfall threshold model with the objective of limiting the effects of uncertainties typically associated with them, such as a lack of robust landslide database, the selection of the contributing rain gauge, seasonal variations in rainfall patterns, and the effect of extreme rainfall conditions. With the aid of gauge-corrected satell...

The Edenville Dam, an earthen embankment in Midland, MI, failed on May 19, 2020, after 3 days of elevated rainfall (3.83–8.0 in.; 9.7–20 cm), which caused flooding downstream of the dam. Dam infrastructure similar to that at the Edenville Dam is not uncommon in the United States and hence requires periodic monitoring. A pre-failure analysis was con...

Flood risk assessment is crucial for delineating flood hazard zones and formulating effective mitigation strategies. Employing a multi-criteria decision support system, this study focused on assessing a Flood Risk Index (FHI) at the Dades Wadi watershed scale. Seven main floodcausing criteria were broadly selected, namely flow accumulation, distanc...

Landslides are among the most perilous hazards that usually happen in hilly terrains. The loss that ensues during a landslide, especially in highly-populated regions, calls for a vulnerability study. Thus, the purpose of this research is to detect landslide-vulnerable villages in a small part of the Western Ghats, an orographic mountain chain in So...

Quantifying landslide volumes in earthquake affected areas is critical to understand the orogenic processes and their surface effects at different spatio-temporal scales. Here, we build an accurate scaling relationship to estimate the volume of shallow soil landslides based on 1 m pre- and post-event LiDAR elevation models. On compiling an inventor...

The coronavirus disease or COVID‐19 pandemic continues imposing restrictions on the human population from full‐scale normal/routine activities all over the world. This study primarily spotlights the consequences of the COVID‐19‐pandemic‐lockdown on physicochemical parameters of water (samples) of the Karamana river sys- tem (KRS) during the pre‐mo...

Quantifying landslide volumes in earthquake affected areas is critical to understand the orogenic processes and their surface effects at different spatio-temporal scales. Here, we build an accurate scaling relationship to estimate the volume of soil landslides based on 1 m pre-and post-event LiDAR elevation models. On compiling an inventory of 1719...

Landslides are prevalent in the Western Ghats, and the incidences that happened in 2021 in the Koottickal area of the Kottayam district (Western Ghats) resulted in the loss of 10 lives. The objectives of this study are to assess the landslide susceptibility of the high-range local self-governments (LSGs) in the Kottayam district using the analytica...

Wildfires are one of the gravest and most momentous hazards affecting rich forest biomes worldwide; India is one of the hotspots due to its diverse forest types and human-induced reasons. This research aims to identify wildfire risk zones in two contrasting climate zones, the Wayanad Wildlife Sanctuary in the Western Ghats and the Kedarnath Wildlif...

Ramgarh is a well-known nearly circular-shaped topographic high structure, that has captivated Indian geologists since the nineteenth century. Ramgarh crater lies in a flat sedimentary terrain within the vast soil-covered plains of the NeoProterozoic Vindhyan Supergroup of Ramgarh village, Baran district, Rajasthan of India. Several studies on the...

Lonar Impact Crater is a simple meteorite impact crater carved out on the ~ 65 Ma old Deccan tholeiitic flood basalts. The crater, though scoured in a basaltic terrain, is still preserved in its most pristine form, with a central crater lake. The geomorphology, geochemistry, geochronology, hydrology, geophysical parameters, and structural aspects o...

Land use and land cover changes (LULCCs) in mountainous areas may increase the susceptibility to landslides due to modifications of topography, vegetation, and material characteristics. Understanding the relation between LULCCs and landslide occurrences is important for landslide prevention and land resources management. In this study, these change...

The paleo-positions of terrestrial meteorite impact craters along with distance and displacement registered since formation due to plate tectonics were deciphered using GPlates, an interactive GIS-based plate tectonic reconstruction and modeling software. The results of the study are intriguing as several craters have traversed across the globe, bo...

Groundwater potential delineation in the Akka basin, southwest Morocco, has been determined through the combination of geospatial techniques and geological data. The geometric average and expected value are two multi-criteria approaches used to integrate a set of factors–data for which the weights of each factor are assigned using the fuzzy logic f...

Ensuring water availability for agriculture and drinking water supply in semi-arid mountainous regions requires control of factors influencing groundwater availability. In most cases, the population draws its water needs from the alluvial aquifers close to villages that are already limited and influenced by current climatic change. In addition, the...

During the last decade, climate change has generated extreme rainfall events triggering flash floods in short periods worldwide. The delimitation of flood zones by detailed mapping generally makes it possible to avoid human and economic losses, especially in regions at high risk of flooding. The Taguenit basin, located in southern Morocco, is a par...

Soil erosion is a severe environmental problem worldwide, especially in tropical regions. The Revised Universal Soil Loss Equation (RUSLE), one of the universally accepted empirical soil erosion models, is quite commonly used in tropical climatic conditions to estimate the magnitude and severity of soil erosion. This study, apart from identifying t...

Flooding is one of the most destructive natural catastrophes that can strike anywhere in the world. With the recent, but frequent catastrophic flood events that occurred in the narrow stretch of land in southern India, sandwiched between the Western Ghats and the Arabian Sea, this study was initiated. The goal of this research is to identify flood-...

In recent years, landslides have become a typical monsoon calamity in the Western Ghats region of Kerala, India. In addition to property damage, heavy rainfall (36% above normal) and multiple landslides (4728) killed 48 people in 2018. This tendency continued throughout the monsoon seasons of 2019, 2020, and 2021, resulting in the deaths of over 10...

The impact origin of Ramgarh crater in India has been a topic of debate for several decades due to its conspicuous morphology, with recent studies confirming the structure as a complex impact crater. In this work, we present the results from an integrated petrographic and geochemical study to evaluate the impact origin of the crater, in conjunction...

The paradigm of plate tectonics has aided in the identification of the journey of continents on the globe, their assembly into supercontinents, disruption, and re‐assembly. Here, we use meteorite impact craters as proxies for tracking the voyage of lithospheric plates. Employing the provisions in GPlates, an interactive geographic information syste...

The surface of the earth is continuously modified by the action of various active geological agents, and one of the resultant is erosion. Climate, lithology, slope, precipitation, temperature, vegetation and anthropogenic activities are the chief controlling factors of erosional processes. The rate of erosion associated with various geomorphologica...

Varkala, along the southwestern coast of Peninsular India, has a unique place in Indian geology and geomorphology due to the presence of coastal lateritic cliffs, which exposes the entire Mio-Pliocene sequence of Warkalli Formation, and is declared as the type area. Stratigraphically, this formation exposes carbonaceous clay with lenses of lignite...

Increased sedimentation is the main problem that affects dam efficiency by reducing storage capacity. Planning for dam construction and maintenance requires design strategies that heavily depend on integrated basin models, properly identifying principal sediment origins within the watershed and qualifying the sediment production rate. In this resea...

Introduction: On the surface of the earth, weathering and erosion are the chief exogenic processes that continuously modify its morphology, affecting both positive and negative relief features. Erosion is chiefly controlled by a combination of several factors such as climate, lithology, slope of the terrain, vegetation, and anthropogenic factors [1...

Accurate rainfall estimates are required to forecast the spatio-temporal distribution of rain-triggered landslides. In this study, a comparison between rain gauge and satellite rainfall data for assessing landslide distribution in a data-sparse region, the mountainous district Idukki, along the Western Ghats of southwestern India, is carried out. G...

The Kachchh Basin is a peri-cratonic rift basin in western India, exposing a vast range of diverse geologic features representing the past 200 million years spanning from the Jurassic Period to the recent. The Basin represents highly rugged terrain in the form of the hilly ranges and pediment surfaces, while the flat terrain in the north is express...

Many researchers studied Martian landslides, and most of these studies are in the Valles Marineris (VM). Those studies are mainly morphologic analysis, estimates of landslide deposit volumes, thermal properties of the landslides, spectral analyses, and mapping and classifying landslides. But, this study created a robust landslide inventory of 682 i...

This paper provides a review of using Interferometric Synthetic Aperture Radar (InSAR), a microwave remote sensing technique, for deformation monitoring of hydroelectric power projects, a critical infrastructure that requires consistent and reliable monitoring. Almost all major dams around the world were built for the generation of hydropower. InSA...

In developing countries and to a certain degree in developed countries too, either climate change (CC) consequences or drivers of CC are alien to the mindset of commoners, who after High School had with/without vocational skills entered the workforce. This deficit or ignorance can be rectified only by adding CC education in the school system. We pr...

The ever-increasing recovery rate of natural resources from terrestrial impact craters over the last few decades across the globe offers new avenues for further exploration of mineral and hydrocarbon resources in such settings. As of today, 60 of the 208 terrestrial craters have been identified to host diverse resources such as hydrocarbons, metals...

Monitoring dams is critical for identifying vulnerabilities affecting its performance and managing the risk of failure. Traditionally, dam monitoring is performed by a combination of visual surveillance and instrumentation. American Society of Civil Engineers (ASCE) has been giving a D grade for the nation’s 91,000-plus dams since the beginning of...

Furious floods have become an omnipresent reality with the dawn of climate change and its transition to adulthood. Since climate change has now become an accepted reality, analysing the factors that favour or disfavour floods are an urgent requirement. Here we showcase the role of paleochannels, a product of migrating rivers, in a catastrophic floo...

Coastal dynamics can rapidly alter beach morphology. In some places, such as the non-barred southern west coast of India, studying changes to beach morphology is a relatively arduous task. Persistent Scatterer Interferometric Synthetic Aperture Radar (PSInSAR), a remote sensing technique that utilizes stacks of radar images for accurate long-term m...

Meteorite impact craters are morphologic features that can develop characteristic radial, centripetal, and concentric drainage patterns. With age, fluvial activity denudes this morphologic feature, thereby erasing the evidence of a prominent geologic event. Apart from morphology and age, the target lithology and climate also influence crater denuda...

The effect of meteorite impact on basement rocks remains widely debated at Lonar Crater, Central India. We investigate an impact melt-bearing rock from the ejecta layer of Lonar to assess the potential interaction of the projectile with the underlying Archean basement. The investigated sample is a melanocratic, aphanitic melt rock comprising glassy...

As one of the oldest crustal blocks in Southern Peninsular India, the Coorg Block has been the focus of investigations related to crustal evolution in the early history of the Earth with implications on Mesoarchean plate tectonic processes. The Coorg Block is dominantly composed of arc magmatic rocks and bordered on the north by the Mercara Suture...

The short-term deformation of Cochin International Airport Limited (CIAL), southwestern India, built on the massive floodplain of the Periyar River, is the topic of inquiry in this study. An unprecedented flood of August 2018 instigated a refined understanding of the ground deformation, if any, of the CIAL property. Persistent Scatterer Interferome...

Lonar Impact Crater (N 19°58'35'' and E 76°30'30''), in Central India, is the only well-preserved, simple, bowl-shaped crater carved out in the continental flood basalts on the Earth [1]. It is a 1.88 km diameter and 150 m deep Quaternary age circular crater in the ~66 Ma Deccan Basalt. The crater is dated to be ~ 570 ± 47 ka by 40Ar/39Ar geochrono...

Karamana River Basin (KRB), set in the tropical monsoon climate (i.e., Koppen’s Am), hosts the drinking water supply to the capital city of Thiruvanathapuram, one of the highly urbanized cities in the southwestern seaboard of India. Primary focus of the study is a scrutiny of future water security status of KRB, amidst the rising population and sub...

Basement deep Lonar impact event: Evidence from impact-melt bearing rock R. Saranya, S. James and K.S. Sajinkumar Department of Geology, University of Kerala, Thiruvananthapuram 695581, Kerala, India Background: The involvement of Archean basement rocks (Peninsular Gneissic Complex) in the Lonar meteorite impact is highly debatable. A few studie...

Persistent Scatterer Interferometry (PSI) techniques are now well established and accepted for monitoring ground displacements. The presence of shallow-seated landslides, ubiquitous phenomena in the tropics, offers an opportunity to monitor and map these hazards using PSI at the regional scale. Thus, the Western Ghats of India, experiencing a tropi...

Copiapite (Fe²⁺Fe³⁺4(SO4)6(OH)2·20 H2O) and rozenite (Fe²⁺(SO4)·4H2O) are secondary hydrous sulfate minerals, mostly formed because of oxygenation and weathering events of primary sulfides on Earth. Acidophiles, including archaea and bacteria, and specifically anaerobic methanogens (methane-producing microorganisms) have been detected in regions wh...

Event-based landslide inventories are important for analyzing the relationship between the intensity of the trigger (e.g., rainfall, earthquake) and the density of the landslides in a particular area as a basis for the estimation of the landslide probability and the conversion of susceptibility maps into hazard maps required for risk assessment. Th...

Event-based landslide inventories are important for analyzing the relationship between the intensity of the trigger (e.g., rainfall, earthquake) and the density of the landslides in a particular area as a basis for the estimation of the landslide probability and the conversion of susceptibility maps into hazard maps required for risk assessment. Th...

Landslides are one of the most common and a destructive natural hazard in mountainous terrain and thus evaluating their potential locations and the conditions under which they may occur is crucial for their hazard assessment. Shallow landslide occurrence in soil and regolith covered slopes are often modeled using the infinite slope model, which cha...

India's Kerala state, sandwiched between the Arabian Sea and the Western Ghats, witnessed a catastrophic flood during the southwest monsoon in mid-August 2018. Unusual precipitation (24% in excess of the normal) coupled with opening of flood gates of dams in the highland and high tide level in the coastal plains were the drivers of the flood. Synth...

Rainfall-triggered landslides are the most common type of mass movement seen along the tropical belt due to the prevalence of monsoons. These landslides can be forecasted by understanding the spatial and temporal rainfall distribution patterns, and subsequent generation of rainfall threshold (RT). However, deriving a regional RT in a geologically,...

Event-based landslide inventories are important for analyzing the relationship between the intensity of the trigger (e.g. rainfall, earthquake) and the density of the landslides in a particular area, as a basis for the estimation of the landslide probability and the conversion of susceptibility maps into hazard maps required for risk assessment. Th...

Dhala Crater, located in the Bundelkhand Craton of Central India, has been contemplated as a complex crater. Here we present the results from a detailed investigation of the morphology of the crater by integrating geoinformatics and subsurface geology. The syn- and post-impact litho-contact, considered as crater boundary, was generated using visual...

From 1 June to 29 August 2018, Kerala, a state in southwestern India, recorded 36% excess rainfall than normal levels, leading to widespread floods and landslides events and resulting in 445 deaths. In this study, satellite-based data were used to map the flood inundation in the districts of Thrissur, Ernakulam, Alappuzha, Idukki and Kottayam. Spec...

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Landslides in Kerala, India, have been shown to be preceded not only by critical rainfall over a short period but also a much longer period of elevated pore pressure. Such rainfall-triggered landslides are difficult to monitor due to a lack of adequate data on the locations of failures and precipitation. Here, a method is presented using Transient...

We report spectral analyses of copiapite and rozenite from Banded Iron Formation in Wayanad in India; could be used as a chemical analogue for copiapite on Mars.