CHSE Odisha Elective Geography cheat sheet

Continental drift (Wegener, 1912) rested on fit of coastlines, matching fossils (Glossopteris), tillites and rock structures; rejected then for lack of a driving mechanism, later explained by plate tectonics.

Sea-floor spreading (Hess, 1960): new oceanic crust forms at mid-oceanic ridges, moves laterally, and is destroyed at trenches; symmetrical magnetic striping on either side of ridges is the key evidence.

Plate boundaries: divergent (ridges, rift valleys), convergent (ocean-ocean island arcs, ocean-continent fold mountains and trenches, continent-continent Himalaya-type collision) and transform (San Andreas type).

Rock cycle: igneous (intrusive/extrusive) -> weathering and erosion -> sediment -> compaction and cementation -> sedimentary -> heat and pressure -> metamorphic -> melting -> magma.

Weathering is in situ breakdown: mechanical (frost shattering, exfoliation, salt weathering) versus chemical (hydrolysis, oxidation, carbonation); erosion involves transport by water, wind or ice.

Fluvial landforms: V-shaped valleys, waterfalls and gorges in the youth stage; meanders, floodplains and ox-bow lakes in maturity; deltas, levees and distributaries in old age.

Karst features (limestone): swallow holes, sinkholes, dolines, uvalas, poljes, stalactites, stalagmites and pillars form by carbonation solution.

Glacial landforms: cirque, arête, horn, U-shaped valley, hanging valley, roche moutonnée, moraine, drumlin, esker and outwash plain.

Davis's cycle of erosion: youth, maturity and old age, ending in a peneplain; Penck proposed ongoing uplift against degradation, and King's pediplanation produces pediplains.

Insolation is concentrated near the equator and oblique near the poles; this differential heating drives pressure gradients, winds and the general circulation.

Pressure belts: equatorial low (doldrums), subtropical highs (horse latitudes), subpolar lows and polar highs; winds blow from high to low pressure deflected by the Coriolis force.

Planetary winds: trade winds (NE in the northern, SE in the southern hemisphere), westerlies and polar easterlies; the ITCZ shifts with the apparent movement of the sun.

Monsoon: seasonal reversal of winds caused by differential heating of land and sea, the shift of the ITCZ and jet-stream dynamics; the Indian monsoon arrives at Kerala around 1 June.

Cyclones: tropical cyclones need sea-surface temperature above about 27 degrees C, high humidity and low vertical wind shear; temperate cyclones are frontal, with warm and cold sectors.

Climate classification (Koppen): A tropical, B dry, C warm temperate, D cold temperate, E polar; Odisha is mostly Aw (tropical savanna), with Am in parts of the coastal belt.

Ocean salinity averages about 35 parts per thousand; it is highest in the subtropical subtropics (about 36-37 ppt) and lower near the equator and at high latitudes due to rainfall and ice melt.

Surface currents are driven by prevailing winds and deflected by the Coriolis force; gyres are clockwise in the northern and anticlockwise in the southern hemisphere; the Gulf Stream and Kuroshio are warm, the Labrador and Humboldt cold.

Tides: spring tides at new and full moon when sun and moon align; neap tides at quadrature; semidiurnal tides dominate most coasts, and tidal range is amplified in funnel-shaped estuaries.

Demographic transition: Stage 1 high birth and death rates, Stage 2 falling death rate with high birth rate, Stage 3 falling birth rate, Stage 4 low stable rates, Stage 5 possible decline.

Natural increase = birth rate minus death rate; doubling time is approximated by 70 divided by the annual percentage growth rate.

Dependency ratio = (population aged 0-14 plus 65 and above) divided by population aged 15-64, multiplied by 100.

Sex ratio in India is expressed as females per 1,000 males; the 2011 Census recorded about 943 nationally and about 979 for Odisha.

Population density = total population divided by area in square kilometres; India recorded 382 per sq km in 2011, Odisha about 270 per sq km.

Malthus argued population grows geometrically while food grows arithmetically; Boserup argued population pressure induces agricultural intensification.

Push factors include poverty, unemployment and conflict; pull factors include jobs, education and better services; Ravenstein's laws note that most migration is short-distance and stepwise.

Settlement types: compact/nucleated, dispersed, linear and circular; urban functions include administration, trade, industry and transport nodes; Primate City rule compares the largest city with the next largest.

Resource classification: renewable versus non-renewable; potential, developed and reserve resources; biotic versus abiotic; on the basis of ownership, individual, community, national and international.

Von Thunen's model: land use rings around a market determined by transport cost and land rent; intensive farming and perishables nearest the market, grazing farthest.

Agriculture types: shifting cultivation, subsistence intensive, plantation, commercial grain farming, mixed farming, dairy, ranching and Mediterranean farming.

Major Indian crops: rice needs 100 cm or more rainfall and clayey loam; wheat needs 50-75 cm and cool growing season; cotton needs black soil and 210 frost-free days.

Green Revolution used HYV seeds, irrigation, fertiliser and pesticides, mainly wheat in Punjab, Haryana and western Uttar Pradesh; Odisha's agriculture is dominated by rice.

Weber's least-cost location theory: the plant locates where transport and labour costs are minimised, modified by agglomeration economies; weight-losing industries locate near raw materials.

Industrial location factors: raw material, power, water, transport, labour, capital, market and government policy; footloose industries are not tied to any single factor.

Iron and steel centres in India: Jamshedpur, Bhilai, Rourkela, Durgapur, Bokaro and Burnpur; Rourkela Steel Plant, built with German collaboration, began production in 1959.

Industrial regions of Odisha: Rourkela (steel), Angul-Talcher (aluminium and power), Jharsuguda (aluminium), Paradip (port and refinery), Balasore and Khurda ( diversified).

India lies between 8 degrees 4 minutes and 37 degrees 6 minutes N latitude and 68 degrees 7 minutes and 97 degrees 25 minutes E longitude; the Tropic of Cancer crosses through eight states.

Physiographic divisions: Himalaya, Indo-Gangetic Plain, Peninsular Plateau, Coastal Plains and Islands; the Western Ghats and Eastern Ghats meet at the Nilgiris.

Odisha lies between about 17 degrees 49 minutes and 22 degrees 34 minutes N and 81 degrees 24 minutes and 87 degrees 29 minutes E, with a 480 km coastline along the Bay of Bengal.

Odisha's physiographic regions: the coastal plains (Balasore, Bhadrak, Kendrapara, Jagatsinghpur, Puri, Ganjam), the central uplands and the western highlands; the Eastern Ghats run north-south.

Major Odisha rivers: Mahanadi (longest within the state, with Hirakud dam), Brahmani, Baitarani, Subarnarekha, Budhabalanga, Rushikulya and Vansadhara; the Mahanadi delta is the state's rice bowl.

Chilika Lake, Asia's largest brackish-water lagoon, lies on the Odisha coast and is a Ramsar site; Similipal in Mayurbhanj is a biosphere reserve and tiger reserve.

Odisha's mineral wealth: iron ore (Keonjhar, Sundargarh), bauxite (Kalahandi, Koraput), coal (Talcher, Ib valley), chromite (Sukinda, Jajpur) and manganese (Keonjhar, Sundargarh).

Climate of Odisha: tropical monsoon, hot and humid summers, monsoon from June to October, mild winters; the state is vulnerable to cyclones from the Bay of Bengal.

Major cities: Bhubaneswar (capital), Cuttack (former capital, judicial hub), Rourkela, Sambalpur, Berhampur and Puri (pilgrimage centre).

Map scale: statement, representative fraction (RF) and graphical/linear scale; RF is unitless, e.g. 1:50,000 means 1 cm on the map equals 0.5 km on the ground.

Conversions: to change RF to statement, multiply the denominator by the map unit and divide by 100,000 to get kilometres; a graphical scale survives map enlargement or reduction.

Large-scale maps show small areas in greater detail (1:10,000 to 1:50,000); small-scale maps show large areas in less detail (1:250,000 and smaller).

Grid reference: eastings are read before northings (read right, then up); a four-figure reference locates a grid square, a six-figure reference locates a point within it.

Contours join points of equal elevation; closely spaced contours indicate steep slopes, widely spaced contours gentle slopes; V-shaped contours pointing upstream mark valleys.

Surveying types: chain or tape, compass (prismatic and surveyor's), plane table (radiation, intersection, traversing, resection), levelling and theodolite traversing.

Chain survey instruments: chain or tape, ranging rods, arrows, cross-staff or optical square, pegs and plumb bob; offsets are measured at right angles to the chain line.

Plane table methods: radiation from a single station, intersection from two stations, traversing around a closed figure, and resection (three-point problem) to locate the plane table.

Remote sensing and GIS: raster versus vector data, resolution, spectral bands, and the use of satellite imagery for land-use and disaster mapping.

Ecosystem components: producers, consumers and decomposers, plus abiotic factors; energy flows one way while nutrients cycle (carbon, nitrogen, oxygen and water cycles).

Food chain and food web: only about 10 percent of energy passes to the next trophic level (ten percent law); biomass pyramids may be inverted in aquatic systems.

Pollution types: air (particulates, SO2, NOx, CO), water (organic load, heavy metals), soil (pesticides, plastics), noise and thermal; BOD and COD measure organic water pollution.

Global environmental issues: ozone depletion by CFCs, greenhouse effect and global warming, acid rain from sulphur and nitrogen oxides, and desertification.

Disaster types: natural (cyclone, flood, drought, earthquake, landslide, tsunami) and man-made (industrial accident, fire, road accident); hazards become disasters when vulnerability is high.

Disaster management cycle: mitigation and preparedness before the event, response and relief during it, and recovery and rehabilitation after it.

Odisha's hazard profile: cyclone-prone coast (1999 super cyclone, 2013 Phailin, 2014 Hudhud), recurrent floods in the Mahanadi delta, drought in the western districts and heat waves.

Structural mitigation: embankments, cyclone shelters, saline embankments, flood forecasting and early warning; non-structural measures include land-use zoning, insurance and public awareness.

Environmental legislation in India: Environment Protection Act 1986, Forest Conservation Act 1980, Wildlife Protection Act 1972, Water Act 1974 and Air Act 1981.

Field study record structure: title, objectives, location and accessibility, methodology, observations and data tables, analysis, conclusion and acknowledgements.

Sampling: random, systematic and stratified; a sample survey should state the sample size and the instrument (questionnaire or schedule) used.

Data presentation: bar graphs for discrete categories, line graphs for time series, pie charts for proportions, choropleth maps for density and isopleth maps for continuous values.

Weather record: maximum-minimum thermometer, dry- and wet-bulb hygrometer for relative humidity, rain gauge for rainfall, wind vane and anemometer for wind direction and speed.

Rainfall statistics: mean, median and mode; range = highest minus lowest value; a simple bar diagram of monthly rainfall reveals the monsoon peak.

Map-based project: locate the study area using grid reference, note relief from contours, drainage, land use and settlement, and correlate them with field observations.

Soil and water tests: soil texture by feel or sieve, pH by indicator paper, and water turbidity by Secchi disc or simple visual comparison.

Viva expectations: explain why the site was chosen, how data were collected, sources of error, and how the conclusion answers the stated objective.

Continental drift (Wegener, 1912) rested on fit of coastlines, matching fossils (Glossopteris), tillites and rock structures; rejected then for lack of a driving mechanism, later explained by plate tectonics.

Sea-floor spreading (Hess, 1960): new oceanic crust forms at mid-oceanic ridges, moves laterally, and is destroyed at trenches; symmetrical magnetic striping on either side of ridges is the key evidence.

Plate boundaries: divergent (ridges, rift valleys), convergent (ocean-ocean island arcs, ocean-continent fold mountains and trenches, continent-continent Himalaya-type collision) and transform (San Andreas type).

Rock cycle: igneous (intrusive/extrusive) -> weathering and erosion -> sediment -> compaction and cementation -> sedimentary -> heat and pressure -> metamorphic -> melting -> magma.

Weathering is in situ breakdown: mechanical (frost shattering, exfoliation, salt weathering) versus chemical (hydrolysis, oxidation, carbonation); erosion involves transport by water, wind or ice.

Fluvial landforms: V-shaped valleys, waterfalls and gorges in the youth stage; meanders, floodplains and ox-bow lakes in maturity; deltas, levees and distributaries in old age.

Karst features (limestone): swallow holes, sinkholes, dolines, uvalas, poljes, stalactites, stalagmites and pillars form by carbonation solution.

Glacial landforms: cirque, arête, horn, U-shaped valley, hanging valley, roche moutonnée, moraine, drumlin, esker and outwash plain.

Davis's cycle of erosion: youth, maturity and old age, ending in a peneplain; Penck proposed ongoing uplift against degradation, and King's pediplanation produces pediplains.

Insolation is concentrated near the equator and oblique near the poles; this differential heating drives pressure gradients, winds and the general circulation.

Pressure belts: equatorial low (doldrums), subtropical highs (horse latitudes), subpolar lows and polar highs; winds blow from high to low pressure deflected by the Coriolis force.

Planetary winds: trade winds (NE in the northern, SE in the southern hemisphere), westerlies and polar easterlies; the ITCZ shifts with the apparent movement of the sun.

Monsoon: seasonal reversal of winds caused by differential heating of land and sea, the shift of the ITCZ and jet-stream dynamics; the Indian monsoon arrives at Kerala around 1 June.

Cyclones: tropical cyclones need sea-surface temperature above about 27 degrees C, high humidity and low vertical wind shear; temperate cyclones are frontal, with warm and cold sectors.

Climate classification (Koppen): A tropical, B dry, C warm temperate, D cold temperate, E polar; Odisha is mostly Aw (tropical savanna), with Am in parts of the coastal belt.

Ocean salinity averages about 35 parts per thousand; it is highest in the subtropical subtropics (about 36-37 ppt) and lower near the equator and at high latitudes due to rainfall and ice melt.

Surface currents are driven by prevailing winds and deflected by the Coriolis force; gyres are clockwise in the northern and anticlockwise in the southern hemisphere; the Gulf Stream and Kuroshio are warm, the Labrador and Humboldt cold.

Tides: spring tides at new and full moon when sun and moon align; neap tides at quadrature; semidiurnal tides dominate most coasts, and tidal range is amplified in funnel-shaped estuaries.

Demographic transition: Stage 1 high birth and death rates, Stage 2 falling death rate with high birth rate, Stage 3 falling birth rate, Stage 4 low stable rates, Stage 5 possible decline.

Natural increase = birth rate minus death rate; doubling time is approximated by 70 divided by the annual percentage growth rate.

Dependency ratio = (population aged 0-14 plus 65 and above) divided by population aged 15-64, multiplied by 100.

Sex ratio in India is expressed as females per 1,000 males; the 2011 Census recorded about 943 nationally and about 979 for Odisha.

Population density = total population divided by area in square kilometres; India recorded 382 per sq km in 2011, Odisha about 270 per sq km.

Malthus argued population grows geometrically while food grows arithmetically; Boserup argued population pressure induces agricultural intensification.

Push factors include poverty, unemployment and conflict; pull factors include jobs, education and better services; Ravenstein's laws note that most migration is short-distance and stepwise.

Settlement types: compact/nucleated, dispersed, linear and circular; urban functions include administration, trade, industry and transport nodes; Primate City rule compares the largest city with the next largest.

Resource classification: renewable versus non-renewable; potential, developed and reserve resources; biotic versus abiotic; on the basis of ownership, individual, community, national and international.

Von Thunen's model: land use rings around a market determined by transport cost and land rent; intensive farming and perishables nearest the market, grazing farthest.

Agriculture types: shifting cultivation, subsistence intensive, plantation, commercial grain farming, mixed farming, dairy, ranching and Mediterranean farming.

Major Indian crops: rice needs 100 cm or more rainfall and clayey loam; wheat needs 50-75 cm and cool growing season; cotton needs black soil and 210 frost-free days.

Green Revolution used HYV seeds, irrigation, fertiliser and pesticides, mainly wheat in Punjab, Haryana and western Uttar Pradesh; Odisha's agriculture is dominated by rice.

Weber's least-cost location theory: the plant locates where transport and labour costs are minimised, modified by agglomeration economies; weight-losing industries locate near raw materials.

Industrial location factors: raw material, power, water, transport, labour, capital, market and government policy; footloose industries are not tied to any single factor.

Iron and steel centres in India: Jamshedpur, Bhilai, Rourkela, Durgapur, Bokaro and Burnpur; Rourkela Steel Plant, built with German collaboration, began production in 1959.

Industrial regions of Odisha: Rourkela (steel), Angul-Talcher (aluminium and power), Jharsuguda (aluminium), Paradip (port and refinery), Balasore and Khurda ( diversified).

India lies between 8 degrees 4 minutes and 37 degrees 6 minutes N latitude and 68 degrees 7 minutes and 97 degrees 25 minutes E longitude; the Tropic of Cancer crosses through eight states.

Physiographic divisions: Himalaya, Indo-Gangetic Plain, Peninsular Plateau, Coastal Plains and Islands; the Western Ghats and Eastern Ghats meet at the Nilgiris.

Odisha lies between about 17 degrees 49 minutes and 22 degrees 34 minutes N and 81 degrees 24 minutes and 87 degrees 29 minutes E, with a 480 km coastline along the Bay of Bengal.

Odisha's physiographic regions: the coastal plains (Balasore, Bhadrak, Kendrapara, Jagatsinghpur, Puri, Ganjam), the central uplands and the western highlands; the Eastern Ghats run north-south.

Major Odisha rivers: Mahanadi (longest within the state, with Hirakud dam), Brahmani, Baitarani, Subarnarekha, Budhabalanga, Rushikulya and Vansadhara; the Mahanadi delta is the state's rice bowl.

Chilika Lake, Asia's largest brackish-water lagoon, lies on the Odisha coast and is a Ramsar site; Similipal in Mayurbhanj is a biosphere reserve and tiger reserve.

Odisha's mineral wealth: iron ore (Keonjhar, Sundargarh), bauxite (Kalahandi, Koraput), coal (Talcher, Ib valley), chromite (Sukinda, Jajpur) and manganese (Keonjhar, Sundargarh).

Climate of Odisha: tropical monsoon, hot and humid summers, monsoon from June to October, mild winters; the state is vulnerable to cyclones from the Bay of Bengal.

Major cities: Bhubaneswar (capital), Cuttack (former capital, judicial hub), Rourkela, Sambalpur, Berhampur and Puri (pilgrimage centre).

Map scale: statement, representative fraction (RF) and graphical/linear scale; RF is unitless, e.g. 1:50,000 means 1 cm on the map equals 0.5 km on the ground.

Conversions: to change RF to statement, multiply the denominator by the map unit and divide by 100,000 to get kilometres; a graphical scale survives map enlargement or reduction.

Large-scale maps show small areas in greater detail (1:10,000 to 1:50,000); small-scale maps show large areas in less detail (1:250,000 and smaller).

Grid reference: eastings are read before northings (read right, then up); a four-figure reference locates a grid square, a six-figure reference locates a point within it.

Contours join points of equal elevation; closely spaced contours indicate steep slopes, widely spaced contours gentle slopes; V-shaped contours pointing upstream mark valleys.

Surveying types: chain or tape, compass (prismatic and surveyor's), plane table (radiation, intersection, traversing, resection), levelling and theodolite traversing.

Chain survey instruments: chain or tape, ranging rods, arrows, cross-staff or optical square, pegs and plumb bob; offsets are measured at right angles to the chain line.

Plane table methods: radiation from a single station, intersection from two stations, traversing around a closed figure, and resection (three-point problem) to locate the plane table.

Remote sensing and GIS: raster versus vector data, resolution, spectral bands, and the use of satellite imagery for land-use and disaster mapping.

Ecosystem components: producers, consumers and decomposers, plus abiotic factors; energy flows one way while nutrients cycle (carbon, nitrogen, oxygen and water cycles).

Food chain and food web: only about 10 percent of energy passes to the next trophic level (ten percent law); biomass pyramids may be inverted in aquatic systems.

Pollution types: air (particulates, SO2, NOx, CO), water (organic load, heavy metals), soil (pesticides, plastics), noise and thermal; BOD and COD measure organic water pollution.

Global environmental issues: ozone depletion by CFCs, greenhouse effect and global warming, acid rain from sulphur and nitrogen oxides, and desertification.

Disaster types: natural (cyclone, flood, drought, earthquake, landslide, tsunami) and man-made (industrial accident, fire, road accident); hazards become disasters when vulnerability is high.

Disaster management cycle: mitigation and preparedness before the event, response and relief during it, and recovery and rehabilitation after it.

Odisha's hazard profile: cyclone-prone coast (1999 super cyclone, 2013 Phailin, 2014 Hudhud), recurrent floods in the Mahanadi delta, drought in the western districts and heat waves.

Structural mitigation: embankments, cyclone shelters, saline embankments, flood forecasting and early warning; non-structural measures include land-use zoning, insurance and public awareness.

Environmental legislation in India: Environment Protection Act 1986, Forest Conservation Act 1980, Wildlife Protection Act 1972, Water Act 1974 and Air Act 1981.

Field study record structure: title, objectives, location and accessibility, methodology, observations and data tables, analysis, conclusion and acknowledgements.

Sampling: random, systematic and stratified; a sample survey should state the sample size and the instrument (questionnaire or schedule) used.

Data presentation: bar graphs for discrete categories, line graphs for time series, pie charts for proportions, choropleth maps for density and isopleth maps for continuous values.

Weather record: maximum-minimum thermometer, dry- and wet-bulb hygrometer for relative humidity, rain gauge for rainfall, wind vane and anemometer for wind direction and speed.

Rainfall statistics: mean, median and mode; range = highest minus lowest value; a simple bar diagram of monthly rainfall reveals the monsoon peak.

Map-based project: locate the study area using grid reference, note relief from contours, drainage, land use and settlement, and correlate them with field observations.

Soil and water tests: soil texture by feel or sieve, pH by indicator paper, and water turbidity by Secchi disc or simple visual comparison.

Viva expectations: explain why the site was chosen, how data were collected, sources of error, and how the conclusion answers the stated objective.