Here are all 132 Geochemistry and Environmental Geology questions asked in UPSC Geology Optional Paper II from 1995 to 2026, arranged under the 6 topics of the official syllabus. Within each topic the latest questions come first.
Each question ends with a code such as [2024/15m/3b] – the year, the marks, the word limit (where UPSC set one) and the question number in the paper.
6.1] Cosmic and earth geochemistry
39 questions
What are the major components of chondrites? Discuss the mineralogical and textural features, and significance of chondrites. [2025/10m/150w/5e]
Discuss briefly about the abundance of elements in the Universe. State Oddo-Harkins rule with examples. [2024/10m/150w/5d]
What are the different layers in the Earth’s interior? How is the layered structure of the Earth determined? Name two most abundant elements of each layer of the Earth. [2024/15m/8a]
Define major, minor and trace elements. Write briefly about the characteristics of lithophile, chalcophile, siderophile and atmophile elements with examples. Why are trace elements considered more efficient than major elements in understanding the Earth’s processes? [2024/15m/8b]
Discuss the causes of various seismic discontinuities in the upper mantle. [2023/20m/8a]
What is the structure of the Earth? Is the Earth compositionally homogeneous or composition of the Earth varies with depth? Write a note on distribution of elements in the Earth. [2022/15m/8b]
Write the classification of meteorites. Discuss importance of study of meteorites in Earth Science. [2022/15m/8c]
Define ‘trace element’. Discuss the possible ways that a trace element can enter into a mineral structure. [2021/10m/150w/5d]
State the characteristic features of cosmic abundance of elements. What are the bases of estimation of cosmic abundance of elements? [2021/20m/7a]
What do you mean by ‘primitive mantle’? Illustrate the cosmochemical and observational constraints on mantle composition. [2020/20m/8a]
Discuss significance of meteorite in cosmochemistry. [2019/10m/5d]
What are general characteristics of ‘lanthanides’? Why is Rare Earth Element (REE) abundances in a rock expressed with the help of chondrite normalized diagram? What is petrogenetic significance of ‘Ce’ and ‘Eu’ anomaly? [2019/20m/8a]
Explain the mineralogical phase changes in the mantle of Earth with depth. [2018/10m/5e]
Give the classification of meteorites. How does the study of meteorites help in understanding the internal composition of the Earth? [2018/20m/8a]
Discuss the texture, composition and types of aerolites. Comment upon the significance of chondrites. [2017/10m/5d]
What do you understand by incompatibility of elements? Comment upon High Field Strength (HFS) and Large Ion Lithophile (LIL) elements. [2017/10m/8c]
Describe briefly the geochemical classification of elements. Add a note on the role of trace elements in magmatic crystallisation. [2016/20m/7b]
While quartz is completely absent in the mantle, why is it the most common mineral on the continents? [2015/10m/2c]
What are the different discontinuities within the earth picked up by seismic waves? What are the petrological explanations for each of these discontinuities? [2015/20m/3a]
Describe internal structure and composition of the earth. Discuss various rules governing distribution of trace elements in the earth’s crust. [2014/20m/8a]
Discuss the mineralogical and chemical compositions of various meteorites, with a note on how meteorites furnish evidence about planetary interiors. [2013/15m/8a]
Write a note on the cosmic abundance of elements and their significance. [2012/20m/4a]
Write short notes on: (i) Chondrite and tektite (ii) Duty and responsibility of sample collector in mineral prospection (iii) Mercury pollution. [2012/30m/6b]
Name and discuss on Antarctic meteorites originating from the Moon. [2012/20m/7a]
Kamacite and octahedrite. [2012/10m/7b(i)]
Meteorite crater in India and its age. [2012/10m/7b(ii)]
Significance of cerium and europium anomalies and La/Yb ratio in the interpretation of sedimentary environment. [2011/10m/1f]
Classification of meteorites and definition of equilibrated chondrite and achondrite. [2011/10m/5d]
Geochemical differentiation of the Earth. [2011/15m/8a]
Role of high field strength elements in the understanding of the petrogenetic processes. [2011/15m/8b]
How does oxygen in atmosphere differ from oxygen in rocks and minerals? [2010/7m/150w/1c(i)]
Describe in details the cosmic abundance of elements. [2010/30m/8a]
Discuss the mineralogical (and chemical) compositions of various meteorites, with a note on how carbonaceous chondrites furnish evidence for planet’s composition. [2009/30m/8a]
Describe the abundance of elements in Sun and in the Earth. Add a detailed note on the general characters and chemical composition of Jupiter and Mars. [2007/30m/8a]
In about 200 words each, write notes on any three of the following: Composition of meteorites, their classification and significance in geological studies. [2004/20m/200w/5c]
Definition of trace elements. Goldschmidt’s rules for the distribution of trace elements and later modifications of these rules. [2004/30m/8a]
Goldschmidt’s geochemical classification of the elements with examples. [2003/30m/8a]
Structure and composition of the Earth. [2002/30m/8a]
Major elements and trace elements in the Earth’s crust. [2001/30m/8a]
6.2] Crystal chemistry and thermodynamics
29 questions
Explain the use of primary thermodynamics in understanding geological processes. [2026/15m/8c]
What do you understand by isomorphism and polymorphism? Discuss monotropy by citing example of diamond and graphite. [2025/20m/8a]
Define polymorphism and discuss different types of polymorphic transitions. What are the different types of polymorphs of and ? [2024/20m/2c]
How does coordination number depend on the ratio of ionic radii in a crystal? [2023/10m/150w/5e]
Explain the phenomena of solid solution and exsolution in minerals. [2022/10m/150w/1b]
Define equilibrium in a system. What are entropy, enthalpy and Gibb’s free energy of a system? [2022/10m/150w/5d]
Discuss briefly with examples about different types of chemical bonds observed in natural minerals. [2021/10m/7b]
Illustrate with examples the role of chemical bonding in minerals in determining certain properties. [2020/10m/5d]
Define thermodynamic phase rule and state its mathematical expression. Determine the degree of freedom for a system under equilibrium with 8 components and 5 mineral phases. Briefly discuss the principle of ACF diagram. [2019/10m/1d]
Define ‘isomorphism’ and ‘polymorphism’ with suitable examples. What are different types of polymorphism? [2019/10m/8b]
Discuss different kinds of interatomic linkages. What are the principles of crystal structures? Comment upon the rules that govern atomic substitution of trace elements in silicates. [2017/20m/8a]
What are the chemical parameters which determine the coordination number of a cation in crystal structure? Illustrate with examples of cations in 3-fold and 4-fold coordination in rock forming minerals. [2015/10m/5d]
Explain how substitution of one element by another takes place in minerals. Write a note on solid solution with example from silicate minerals. [2015/10m/7d]
What is polymorphism in minerals? Explain with suitable examples from rock forming minerals and ore minerals. [2015/10m/8c]
Explain how the radius ratio of cation to anion influences coordination in minerals. Cite examples of two common coordination in rock forming minerals. [2013/10m/1a]
Define the Gibbs phase rule and calculate the variance of the assemblage containing enstatite + forsterite + Mg-spinel + Mg-cordierite + corundum in the appropriate chemical system. [2013/10m/1b]
From the first and the second laws of thermodynamics and assuming reversible process, derive the expression ; where U, S, T, P and V respectively stand for internal energy, entropy, temperature, pressure and volume. [2013/10m/5d]
What is chemical equilibrium? With suitable example, explain the consequence of disturbance of the equilibrium state in rocks. [2010/15m/150w/1a]
Briefly explain the laws of isomorphous substitution of elements and give examples wherever necessary. [2010/15m/150w/5c]
Explain how radius ratio (of cation to anion) influences coordination in silicate minerals. Write how an element can have more than one coordination number? [2009/20m/200w/1a]
Define the Gibbs phase rule and calculate the variance of the assemblage containing enstatite + forsterite + Mg-spinel + corundum. [2009/20m/200w/1b]
Explain how on the basis of ionic radius and charge, atomic substitution take place in silicate minerals. What is the effect of electronegativity on the above substitution mechanisms? [2009/20m/200w/5c]
In about 200 words each, write notes on any three of the following: Isomorphism and isomorphous mixture, examples. [2003/20m/200w/5c]
In about 200 words each, write notes on any three of the following: Types of chemical bonds. [2002/20m/200w/5b]
Pseudomorphism. [1999/20m/200w/1c]
Co-ordination number. [1998/20m/200w/1d]
Taking plagioclase feldspars as an example, illustrate the phenomenon of solid solution. [1998/60m/2]
Polymorphism. [1997/20m/200w/1b]
Isomorphism. [1996/20m/200w/1a]
6.3] Natural hazards
26 questions
What are the causes of earthquakes and volcanic activities? Discuss their mitigation possibilities. [2026/20m/8a]
Describe the natural hazards due to earthquakes. Discuss the mitigation aspects of earthquake hazards. [2024/10m/150w/5e]
Discuss the hazards in active volcanic terrain during and after eruption. [2023/15m/8c]
Give the classification of landslides and discuss the causes of landslide. [2022/20m/8a]
How is unscientific development of catchments situated in mountainous regions responsible for increased threat of floods in plains? [2021/10m/8a]
Explain about the impact of volcanic eruptions on the environment. [2020/20m/8b]
Briefly mention measures to mitigate landslides. [2020/10m/8c]
Illustrate different type of mass wasting processes with suitable examples. Enumerate preventive measures for the mitigation of hazards from mass wasting. [2018/20m/8b]
What is an earthquake? Discuss briefly the main causes of earthquake. How earthquake intensity is measured? [2016/10m/6c]
Explain marine erosion as a coastal hazard and list its mitigation-measures. [2014/10m/5d]
What do you understand by Landslides? Discuss briefly various types of landslides. Comment upon causes and remedial measures of landslides. [2014/15m/8b]
Describe Reservoir Induced Seismicity (RIS) with a particular reference to Koyna earthquake. [2014/15m/8c]
Discuss the effects of river flooding and response to flood hazards. [2013/15m/8b]
Explain the role of water in slope stability and add a note on types of slope failure. [2013/20m/8c]
How do earthquakes cause tsunami? [2010/15m/150w/5d]
Why is solifluction more common in cold climates than in temperate climates? Name and explain the key factors that control Mass Wasting. What role does water play in various types of Mass Wasting? [2010/30m/8b]
Discuss the precursor events that might signal the occurrence of an earthquake. [2009/20m/200w/5d]
Discuss the various causative factors behind different types of mass wasting. [2009/30m/8b]
Earthquakes: Their predictions, and remedial measures for mitigation. [2007/20m/200w/5d]
What are Natural Hazards? Describe any four of them with their impact on the Environment. Also add a note on the Mitigative measures of any two of them. [2007/30m/8b]
In about 200 words each, write notes on any three of the following: Earthquake risk in India. [2006/20m/200w/5c]
Types of natural hazards with reference to damage and control of floods in India. [2006/30m/8b]
Describe how floods in a given region are related, as a geologic phenomenon, to precipitation, soil characteristics, vegetation and season. [2005/60m/8]
Landslides as natural hazards, their causes, impacts and measures of their mitigation. [2004/30m/8b]
Impact of natural hazards on environment. Mitigating measures of any one of these natural hazards. [2002/30m/8b]
Mitigation of natural hazards in Himalayan terrain. [2001/30m/8b]
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20 questions
Discuss the environmental cost of growing urbanization. How can sustainability be ensured? [2026/10m/150w/5e]
What are the most important conditions necessary for safe disposal of radioactive waste in geological repositories? Add a note on the concept of multiple barriers to protect biosphere and hydrosphere. (Give suitable diagrams wherever necessary.) [2025/15m/8b]
What are the major environmental considerations while treating with the disseminated precious metal mine waste? [2025/15m/8c]
Discuss environmental impacts of urbanization and their mitigations with special reference to land and water. [2023/10m/150w/5d]
Discuss the composition, source, types, environmental hazard and utility of fly ash. [2023/15m/8b]
Discuss about environmental hazards caused due to mining. [2022/10m/150w/5e]
Describe various types of radioactive wastes. Write an account on various methods of their disposal. [2021/20m/8b]
What is meant by waterlogging? Describe in detail the remedial measures of waterlogging and salinity. [2021/20m/8c]
What are different types of radioactive waste forms? How are they disposed in geological repository? [2019/20m/8c]
What is high-level nuclear waste? How is it managed and safely disposed in a geological repository? Add a note on its Indian scenario. [2017/20m/8b]
What are the methods of underground mining of mineral deposits? Add a note on impact of underground mining on ground surface and environment. [2015/15m/6d]
Describe different types of radioactive wastes. Write a note on the methods of disposal of radioactive wastes. [2015/10m/8d]
Discuss the various causes and environmental impacts of acid mine drainage. [2013/10m/5e]
Describe effects of long term application of nitrate fertilizers on ground water regime. [2012/12m/5e]
Radioactive waste disposal. [2011/15m/8d]
In about 200 words each, write notes on any three of the following: Environmental effects of opencast mining. [2006/20m/200w/5a]
Anthropogenic toxic elements in urban environment. [2006/30m/8a]
Soil erosion as a threat to environment and crop production. [2005/20m/200w/5d]
In about 200 words each, write notes on any three of the following: Environmental impact of opencast mining. [2004/20m/200w/5d]
In about 200 words each, write notes on any three of the following: Fertilizers and their impact on groundwater pollution. [2003/20m/200w/5d]
6.5] Pollution and environmental protection
13 questions
What are the causes of groundwater and surface water pollution? Explain. [2026/10m/150w/5d]
What is the status of legislative measures for environmental protection in India? Discuss. [2026/15m/8b]
Discuss in detail the pollution of surface water and groundwater due to mining activities. [2024/20m/8c]
How is ground water of coastal areas contaminated by seawater intrusion and comment on its mitigation. [2019/10m/5e]
What are the sources of groundwater pollution? Suggest preventive measures to control groundwater contamination. [2018/10m/8c]
Discuss coal mine water pollution and its impact on groundwater regime. Comment on the preventive measures to be taken to control groundwater pollution. [2017/10m/5e]
Discuss briefly the problem of fluoride contamination in groundwater giving emphasis on its distribution and related health hazards. [2016/20m/6b]
Enumerate the legislative measures in India for environment protection. [2016/10m/8c]
What are the sources of marine pollution and their effect on marine eco-system? [2015/10m/5e]
Explain marine pollution in India. Comment on the analytical techniques that are widely used for determining toxic elements in water. [2012/20m/8c]
Legislative measures for environmental protection in India. [2003/30m/8b]
In about 200 words each, write notes on any three of the following: Pollution of sea. [2002/20m/200w/5d]
In about 200 words each, write notes on any three of the following: Pollution of ground and surface water. [2001/20m/200w/5d]
6.6] Sea level changes
5 questions
Explain the causes and impacts of sea-level rise. [2026/10m/150w/5b]
State the sea level changes in Late Pleistocene period with possible causes. Add a note on anthropogenic causes occurred in last two centuries. [2021/10m/150w/5e]
Write about the causes of Sea level changes. [2020/10m/5e]
Write on the sea-level changes through the geological history, and the associated environment and life, as known from fossil and sedimentary records. [2012/20m/8b]
Causes and effect of sea level changes. [1997/20m/200w/1b]
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Last updated: 31 October 2026