Applied Geomorphology: Meaning, Applications & Techniques

• Applied geomorphology is the use of knowledge about landforms, geomorphic processes and earth materials to solve practical problems of land occupancy, resource use, construction, hazards and planning.
  • It is the practical face of a discipline whose nature and scope cover the form, origin and evolution of the land surface.
• Properly read, a landscape reveals its structure, lithology, soils, water and history, and therefore what the ground will allow and where it will fail.
• Its three classic concerns are geohydrology, economic geology and environment; its working tools are geomorphological mapping, terrain evaluation, remote sensing, GIS and field measurement.

Meaning and Scope

Definitions

• David K.C. Jones (1980): applied geomorphology is the application of geomorphic understanding to the analysis and solution of problems concerning land occupancy, resource exploitation, environmental management and planning.
• R.G. Craig and J.L. Craft (1982) argued that all geomorphological research is in a sense applied, since every advance in knowing how the earth works can be used to evaluate resources, judge projects and reduce hazards.
• The field has three aims:
  • to study how geomorphic and environmental processes affect human society and its activities;
  • to study the changes human activities bring about in those processes, and the problems that follow;
  • to manage resources and monitor change in geomorphic systems so that development stays sustainable.

Two Lines of Application

• Richard J. Chorley, Stanley A. Schumm and David E. Sugden (1984) divided the field into two lines.

• The first line has grown into anthropogeomorphology, which treats the human being as a geomorphic agent; the second line is the core of applied practice.

Fields of Application

• Herman Th. Verstappen (1983) listed the main fields where geomorphic knowledge and survey are applied:
  1. topographic and thematic mapping of natural resources;
  2. survey and reduction of natural hazards: landslides, avalanches, earthquakes, volcanism, subsidence, floods and droughts;
  3. rural development: land use, control of soil erosion, channel manipulation and watershed management;
  4. urbanisation, mining and construction;
  5. engineering design.

Branches of Applied Geomorphology

Applied Geomorphology in India

• Early work:
  • geomorphologists at the Central Arid Zone Research Institute (CAZRI), Jodhpur assessed erosion and land use in the central Luni basin as early as 1968;
  • Ram Lochan Singh at Banaras Hindu University began, in the 1960s, the study of landforms and rural settlements.
• Main Indian themes since then:
  • geomorphic control of rural settlement and urban growth;
  • land-use and agricultural planning, including morpho-agricultural regionalisation;
  • soil erosion, gully and ravine management;
  • groundwater and water resources in the Thar;
  • aeolian hazards and sand movement;
  • flood hazards in the Ganga plain;
  • coastal and mangrove environments such as the Sundarbans.
• Present-day agencies apply it routinely:

Fields of Application

Geomorphology and Hydrology

• Surface water and groundwater occur, move and are polluted differently in each landform, lithology and stratigraphic setting, so terrain analysis is the first step of any water survey.

Karst Terrains

• Permeability in limestone is of two kinds:
  • primary: original interconnected voids, joints and cavities formed with the rock;
  • secondary: openings made later by faulting, folding and warping and by solution; it is greatest beneath and beside valleys.
• Evolution of water supply:
  • early in the karst cycle surface drainage behaves as in other terrains;
  • as sinkholes and swallow holes open, surface water disappears underground, and people come to depend on karst springs.
• Contamination:
  • water entering sinkholes moves down fast and unfiltered, so springs may carry pollutants and bacteria;
  • the feeding sinkholes are traced with dye (fluorescein) tests, helped by the rule that groundwater moves down the regional dip.
• Siting wells:
  • porous limestone capped by sandstone gives large, naturally filtered yields;
  • dense limestone with only secondary openings gives low or contaminated yields.
• Limestone makes a poor reservoir floor, since solution channels leak and demand costly grouting.

Glaciated Terrains

• Good aquifers: outwash plains, valley trains and intertill gravels.
• Poor aquifers: most tills, because of their clay, though sand and gravel lenses within them can meet domestic needs.
• Buried preglacial and interglacial valleys filled with gravel hold large reserves; they are found by reconstructing the bedrock topography and the area’s geomorphic history.

Alluvial Plains and Palaeochannels

• Sandy alluvial aquifers, as in the Ganga plain, hold India’s largest groundwater reserves.
• Buried palaeochannels, such as those traced by satellite imagery in the Ghaggar region of Haryana and Rajasthan, mark sandy, water-bearing belts in otherwise dry country.
• Under the National Aquifer Mapping and Management programme (NAQUIM), the CGWB mapped the country’s mappable area of about 25 lakh sq km by March 2023, combining geomorphic, geophysical and borehole data into aquifer maps.

Geomorphology and Mineral Exploration

• Economic geology depends on geomorphology because ore bodies are tied to structure, structure is expressed in landscape, and many deposits formed under particular past cycles of erosion and climates.

Surface Expression of Ore Bodies

• Positive relief:
  • resistant quartz veins stand out as ridges (Chihuahua, Mexico);
  • the lead-zinc lode of Broken Hill, Australia, formed a conspicuous ridge.
• Negative relief: veins of soluble minerals such as calcite, and some mineralised zones, form depressions or subsidence hollows.
• Other indicators: outcrops, gossan (iron-stained weathered cap), faults, fractures and breccia zones.

Weathering Residues

• Residual minerals include bauxite, laterite iron ore, clay minerals, caliche, and some manganese and nickel ores.
• They are best preserved on old, stable planation surfaces:
  • on Tertiary erosion surfaces above present base level;
  • there, residues stay in place instead of being stripped during the youthful and mature stages of a cycle.
• Denudation chronology, the dating of these surfaces, therefore guides the search.
• Indian example: the pat lands of the Ranchi plateau and Palamau upland (Jharkhand), such as Bagru, are flat-topped mesas where long tropical weathering of basalt removed silica and left a hard, aluminium-rich bauxite crust (alcrete) within the laterite cap.

Placer Deposits

• Placers are concentrations of heavy, durable minerals (gold, platinum, tin, diamond, ilmenite, monazite, zircon) left by weathering and sorting by geomorphic agents.
  • Each type forms in a specific topographic position, which is why landform analysis locates it.

• India’s beach placers on the Kerala (Chavara), Tamil Nadu (Manavalakurichi) and Odisha (Chhatrapur) coasts yield ilmenite, rutile, zircon, garnet, sillimanite and thorium-bearing monazite.
• Exploration:
  • magnetic surveys help because magnetite accompanies gold;
  • over basic bedrock, magnetic lows can mark gravel-filled channels;
  • test drilling and air-photo interpretation complete the survey.
• William D. Thornbury held that reconstructing the geomorphic history of an area is the most fundamental step in finding buried placers.
• Related landforms, such as bajadas and pediments and beaches and strandlines, therefore double as prospecting guides.

Petroleum Exploration

• Oil and gas migrate into porous reservoir rocks (sandstone, limestone) sealed by an impermeable cap (shale), and collect in traps:
  • structural traps: anticlines, domes and fault blocks;
  • stratigraphic traps: pinch-outs and, above all, unconformities.
• Arville I. Levorsen stressed that many fields lie along unconformities, so the petroleum geologist works with buried landscapes.
• Geomorphic clues:
  • topographic highs over anticlines;
  • tonal patterns on air photos under dense forest;
  • drainage anomalies, such as radial or deflected streams, where dips are low and relief is slight.
• Indian examples: the Digboi field of Assam lies in an anticline of the Tertiary fold belt; Mumbai High is an offshore domal structure.
• Extraction carries environmental costs of its own: pits, spoil heaps, mining subsidence, acid and silt-laden drainage, and lowered water tables.

Geomorphology and Engineering Works

Roads and Railways

• Route selection needs knowledge of structure, lithology, stratigraphy, strength of surface deposits, porosity, joints and the geomorphic history of the ground.

• Permafrost engineering:
  • early tundra building in North America and the first Trans-Siberian track deformed as permafrost thawed;
  • this gave rise to geocryology and to dedicated institutes, the Melnikov Permafrost Institute at Yakutsk and the US Cold Regions Research and Engineering Laboratory (CRREL) at Hanover, New Hampshire;
  • hot-oil pipelines need similar precautions.
• Subgrade:
  • a highway’s life depends on its aggregate and on the texture and drainage of its subgrade soil;
  • silty clay over a high water table performs worst, granular material over a low water table best.
• Himalayan example:
  • the Silkyara tunnel on the Char Dham route (Uttarakhand) collapsed on 12 November 2023, trapping 41 workers, all rescued on 28 November;
  • the event renewed demands for detailed geomorphic and geological survey of fractured, weak Himalayan rock before excavation.

Dams and Reservoirs

• Kirk Bryan set out five geologic requirements of a good reservoir site:
  1. a watertight basin of adequate size;
  2. a narrow outlet with a sound foundation for an economical dam;
  3. room for a safe spillway;
  4. construction materials nearby, especially for earthen dams;
  5. a reservoir life not cut short by siltation.
• Data a geomorphologist supplies:
  • valley cross-section and long profile, channel gradient, rock hardness and permeability;
  • slope stability of the valley sides;
  • catchment rainfall, runoff and sediment yield.
• Drainage-basin morphometry helps too: stream orders, catchment area, discharge and sediment load can be estimated at each confluence.
• Ideal dam site: a narrow, constricted valley in resistant rock, with a large catchment, low sediment load and an impermeable reservoir floor.
• Hidden risks:
  • limestone foundations with irregular solution surfaces;
  • buried preglacial valleys full of gravel beneath an apparently ideal gorge, where a dam would leak;
  • reservoir-induced seismicity, as at Koyna (Maharashtra, 1967).

Airstrips

• Good sites need:
  • an extensive, nearly level surface of resistant material;
  • freedom from floods;
  • low fog frequency and good visibility.
• These are read directly from a morphological map.
• High-altitude landing grounds in Ladakh, such as Daulat Beg Oldi, show how few sites meet them in mountains.

Sand and Gravel

Geomorphology and Urbanization

• Urban geomorphology, as defined by Ronald U. Cooke and colleagues (1982), studies landforms and their related processes, materials and hazards in ways useful for planning, developing and managing urban areas or areas where urban growth is expected.
  • The lithology, topography, processes and hydrology of a site govern the size, rate and stability of urban growth.
• The urban geomorphologist’s role is two-fold:
  • before development: field survey, terrain classification and choice of alternative safe sites for particular uses;
  • during and after development: the impact of natural events on the city, and of the city on its environment.
• Fragile zones for urban growth:
  • unstable hillslopes on weak rock;
  • flood-prone riverine lowlands;
  • subsiding ground;
  • receding cliffs;
  • seismically active belts.
• Typical failures:
  • foundations settling in drylands and periglacial areas;
  • foundations destroyed by weathering;
  • flood damage in humid subtropics;
  • squatter settlements on unsuitable land in fast-growing cities of the developing world.
• Indian examples:
  • Ganga plain cities: Prayagraj, Varanasi and Patna have spread onto low kachar floodplain, bringing floods, waterlogging, weak foundations and poor drainage;
    • repeatedly raising embankments protects them only for a time, since it speeds siltation and raises the bed;
    • at Prayagraj, growth is better directed to higher ground such as Jhusi and Phaphamau.
  • Chennai (2015) flooded partly because the city had built over lakes, wetlands and natural drainage lines.
  • Joshimath (2023): satellite radar recorded the town sinking about 5.4 cm in 12 days in early January.

Geomorphology and Hazard Management

• Hazard and disaster:
  • a hazard is a natural or human-induced process or extreme event exceeding tolerable magnitude;
  • a disaster is its result: sudden, severe loss of life and property.
• Chorley, Schumm and Sugden define a geomorphic hazard as any change, natural or man-induced, that may affect the geomorphic stability of a landform to the adversity of living things.

• Volcanoes:
  • eruptions are forecast by monitoring seismic tremors, ground tilt, temperature of crater lakes and hot springs, gas output, and changes in gravity and magnetic fields;
  • the paths of lava flows and lahars (volcanic mudflows) are predicted from detailed topography and likely vents.
• Floods:
  • channel morphology, river metamorphosis and bank form guide five kinds of control:
    1. delay the return of storm runoff to rivers;
    2. hasten discharge by straightening meanders;
    3. divert flow through diversion channels;
    4. confine it with embankments;
    5. forewarn of floods.
  • Levees built without knowing upstream erosion and sediment load cause bed aggradation and catastrophic floods when breached, as when the Kosi broke its embankment at Kusaha in 2008.
• Earthquakes:
  • earthquakes may be natural or man-induced, as around large reservoirs;
  • geomorphic evidence of active faults and unstable terrain identifies weak zones for zoning.
• Landslides:
  • mapping of slope instability and lithology marks slopes to avoid for settlement and roads;
  • GSI’s National Landslide Susceptibility Mapping covers about 4.3 lakh sq km of hilly India at 1:50,000;
  • since the 2025 monsoon GSI has issued landslide forecast bulletins for 21 districts, including Darjeeling, Kalimpong and the Nilgiris;
  • NRSC’s Landslide Atlas of India (2023) catalogued about 80,000 landslides (1998–2022) and ranked Rudraprayag and Tehri Garhwal the most exposed districts.

Geomorphology and Regional Planning

• Planning units:
  • administrative units (state, district, block) cut across natural units, breaking the continuity of resources;
  • the drainage basin is the logical geomorphic unit, with relief, fluvial process and human problems broadly uniform within it.
• River-valley models:
  • the Tennessee Valley Authority (1933) managed a whole watershed for floods, soil erosion, land use, reforestation, navigation, hydropower and public health;
  • its success inspired multipurpose basin bodies such as the Damodar Valley Corporation (1948) in India.
• Chambal ravines show why process knowledge matters:
  • ravination has turned large tracts into badlands, shaped local society and long sheltered outlaws;
  • reclamation depends on understanding gully erosion.
• Planner’s inputs, whatever the unit: terrain classification, soils, channel and runoff characteristics, and groundwater.

Geomorphology and Military Geology

• World War I, a static trench war, drew mainly on geology: rock for trenches and tunnelling, and water supply.
• World War II’s blitzkrieg made terrain trafficability decisive, and terrain analysis became central to planning.
• A geomorphologist reads landforms as systematic, related forms that reveal bedrock, soils, drainage and vegetation.
  • From air photos and maps this predicts water supply, going conditions, construction materials, cover and movement.
• The same terrain intelligence governs high-altitude operations and logistics along India’s Himalayan frontier.

Other Applications

• Soil survey: soil maps are largely topographic maps, since members of a soil series differ with topographic position.
• Coastal engineering succeeds only when built on an understanding of shoreline processes.
• Soil erosion control means managing sheet wash, gullying, mass wasting and stream erosion:
  • severity depends on permeability as well as slope;
  • steep permeable slopes may erode less than gentle impermeable ones.
• Land classification, watershed and river management and coastal zone management rest on the same terrain appreciation.

Techniques of Applied Geomorphology

• Core tasks:
  • mapping landforms and slope elements that affect human activity;
  • interpreting air photos and satellite images;
  • monitoring environmental change;
  • diagnosing the causes of unsustainable change;
  • proposing remedies.

Geomorphological Mapping and Terrain Evaluation

• Morphological maps record breaks of slope, slope units, landforms, materials and active processes, at scales suited to the project.
• Terrain evaluation divides land into land systems and smaller facets that recur with similar form, soil and vegetation.
  • Information gathered on one facet is then transferred to all similar facets, the basis of rapid engineering and military surveys.
• Hazard zonation maps (landslide, flood, seismic) combine these units with process data.

Aerial Photographs and Satellite Imagery

• Air photographs, taken at various scales and viewed stereoscopically, show landforms in three dimensions and keep maps up to date.
• Satellite images support mineral prospecting, land-use inventories, crop forecasting and weather forecasting, and track change over time.

Remote Sensing

• Remote sensing gathers information about objects without contact:
  • sensors record electromagnetic radiation reflected or emitted by the surface;
  • each material has its own spectral signature, the key to image interpretation.
• Platforms: most earth-observation satellites orbit at roughly 500–900 km.
• Radar (microwave) sensors see through cloud and work at night; optical sensors do not.

GIS, DEMs and Radar Interferometry

• Geographical Information Systems (GIS) store, integrate and analyse spatial data layers:
  • slope, geology, land use and rainfall combine into susceptibility and suitability maps;
  • ISRO’s Bhuvan geoportal serves such layers for India.
• Digital elevation models (DEMs), from CartoDEM (Cartosat-1), SRTM or LiDAR, automate slope, drainage and basin morphometry.
• InSAR (radar interferometry) measures ground movement of millimetres to centimetres, used for subsidence, landslides and fault creep.
  • The NASA-ISRO NISAR satellite, launched on 30 July 2025 with L- and S-band radar, maps such deformation repeatedly over nearly all land.

Field and Process Measurement

• Field survey remains the check on every remotely sensed map.
  • It covers ground truth, sediment and soil sampling, borehole logs and geophysical surveys.
• Process measurement quantifies the rates that plans must allow for:
  • erosion pins, sediment gauging, slope inclinometers, piezometers, tiltmeters and GPS stations.

Evaluation

Strengths and Limits

• Strengths:
  • it links process knowledge to decisions on land, water and construction;
  • a geomorphic survey is a cheap early screen that can steer a project away from unstable, flood-prone or leaky ground;
  • hazard mapping built on landform evidence reduces disaster losses.
• Limits:
  • landscapes respond non-linearly; Schumm’s geomorphic thresholds and complex response make exact prediction difficult;
  • scale mismatch: processes are measured on plots over years, while plans cover regions over decades;
  • classical applied work was largely qualitative, whereas engineers need design numbers;
  • geomorphologists are often consulted late or not at all, as Himalayan road, tunnel and town failures show.

Current Directions

• Quantitative, data-rich practice: DEMs, InSAR and repeat imagery feed statistical and machine-learning susceptibility models, checked in the field.
• Climate change is raising the frequency of extreme rain, floods, landslides and coastal erosion, so hazard maps must be dynamic rather than fixed.
• Working with natural processes: river restoration, giving floods room on floodplains, and mangrove and dune buffers in place of hard defences alone.
• Institutional use: geomorphic evidence now enters environmental impact assessment, the Disaster Management Act (2005) framework and NDMA’s landslide risk strategy (2019).