IAS Main Geology Question Paper II- 2010

The Union Public Service Commission (UPSC) holds the Civil Services Examination every year in two parts, i.e. Preliminary Test and Main Examination; the Main Examination comprises a written Test and a Personality Test. The Question paper of the IAS Main Geology Paper II - 2010 is given as below:

GEOLOGY

Paper-II

Time Allowed: Three Hourse

Maximum Marks: 300

Each question is printed both in Hindi and in English.

Answer must be written in the medium specified in the Admission Certificate issued to you, which must be stated clearly on the cover of the answer-book in the space provided for the purpose. No marks will be given for the answers written in a medium other than specified  in the Admission Certicate.

Candidates should attempt Question Nos. 1 and 5 which are compulsory. and any three of the remaining questions selecting at least one question from each Section.

Candidates should draw diagrams wherever necessary.

All questions carry equal marks.

Section A

1. Attempt the following in about 150 words each: 4×15=60

(a) What is chmical equilibrium ? With suitable example, explain the consequence of disturbance of the equilibrium state in rocks.

(b) Explain how on the bases of chemistry and optical properties, the various feldspars differ from one another.

(c) (i) How does oxygen in atmosphere differ from oxygen in rocks and minerals ?   7

(ii) Can ice the called a mineral?  4

(iii) Can a glacier be called a rock ? 4

(d) Discuss the factors that control melting temperature in igneous rocks. How magmas of different composition evolve ?

2. Discuss with sketches:    3×20=60

(a) Double refraction

(b) Determination of optic sign of biaxial minerals

(c) Symmetry elements in crystals

3.(a) (i) What is the difference between biogenous and terrigenous sediments ?   5

(ii) Why is burila necessary to form a sedimentary rock ?  5

(iii) Why are most beds of sedimentary rocks formed horizontally ?           5

(iv) How. are the provenances of heavy minerals in sedimentary rocks identified ?  5

(b) What are the effects of temperature, confining pressure and different stresses on metamorphic minerals and textures of metamorphism in rocks ? What are the different sources of heat for metamorphism ?    20

(c) What are the differences between    20

(i) cleavage and external  crystal form and

(ii) colour and streak of a mineral ?

4. (a) What do mud cracks tell about the envirinment of deposition of a sedimentary rocks? How does a graded bed form ? How does a sedimentary braccia differ in appearance and origin from a conglomerate ? What is an" Evaporite deposit" and how does it form ?   30

(b) What role do gases play in volcanism ? What does " Pillow Structure" indicate about the enviroment of volcanism ? What determines the viscosity of a lava ? Why are extrusive rocks fine grained ?    30

Section 'B'

5. Answer the following in about 150 words each: 4×15=60

(a) What is "Tenor" of an ore ? What are " Assay Width" and " Average Width" of an ore body ? Sates different methods of mine sampling. How does sampling help in determination of are reserve  ?

(b) What are the different types of mineral depositd, where

(i) Magnetic

(ii) Self-potential

(iii) Resistivity and

(iv) Gravity methods of Geophysical prospecting are applied.

(c) Briefly explain the laws of isomorphous substitution of elements and give examples wherever neceaasry.

(d) How do earthquakes cause tsunami ?

6. (a) Compare the lithological associations of sedimentary and magmatic iron are deposits. Name the locations of these two types of deposits found in India. Describe the geology, mineralogy and mode of formation of any important sediomentary iron are deposit of India.  30

(b) How oil and natural gas form in nature ? What geologic factors make them an economically exploitable reserve. Briefly describe the hydrocarbon occurrences in the Bombay High.  30

7. (a) Distinguish between contact metamorphic and contact metasomatic are depositd. Give Indian examples of such deposits. How does porphyry copper deposits form in nature. Add a note on Malanjkhand copper are deposit.  30

(b) Enumerate in detail hydrogeochemical and biogeochemical prospecting methods. How Pedogeochemical prospecting helps in prospecting mineral deposits ? Add a note on geochemical sampling.  30

8. (a) Describe in detail the cosmic abundance of  elements.    30

(b) 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 ?  30