l.
Differentiate between magmatic differentiation and assimilation.

Discuss the basic differences in the crystal structures, physical and optical properties of pyroxene and amphibole.

Enumerate briefly on how the clastic rocks are classified on the basis of their grain-size.

Describe briefly the different types -of twinning commonly found in minerals. Comment upon causes of twinning.

Explain why all pleochroic minerals are anisotropic but all anisotropic minerals are not pleochroic.

2.
With neat sketches describe the symmetry elements and forms of the normal class of the orthorhombic system. Name three minerals of this class.

Give an account of the atomic structure, chemical composition, and physical and optical properties of the minerals of mica group.

A mineral section remains dark in all positions under crossed polars. How would you proceed to determine whether the mineral is isotropic, uniaxial or
(iii)biaxial

3.
Discuss Bowen's Reaction Series. What is it significance in the process of crystallization of magma?

Briefly discuss the classification of sandstones, What is the general tectonic environment in which quartz arenites are found?

With neat sketches describe the textures and structures of metamorphic rocks.

4.
Discuss the origin of anorthosites.
What are heavy minerals? Discuss their significance in sedimentological studies.

ACF diagram
AKF diagram

5.
In a mineral, the refractive indices are' determined as w=1·548 and 1·634:.
Calculate the birefringence of the mineral and comment on its optic nature.

Briefly discuss the different ore-forming processes in sedimentary environment.

What is rank of coal Discuss the general changes that coal may undergo during its increase in rank.

Describe the distribution of gold deposits in India.

Describe the mineralogy, chemical composition and occurrences of manganese nodules in Indian Ocean'.

6.
How oil reserves are formed and accumulated in nature? What are the different types of oil traps? Illustrate with neat diagrams.

(b)Discuss briefly the problem of fluoride contamination in groundwater giving emphasis on its distribution and related health hazards.

What is an earthquake? Discuss briefly the main causes of earthquake. How earthquake intensity is measured?

7.
What are the common methods adopted for resistivity survey in an area? Describe briefly their field procedures and working principle. Also discuss advantages, disadvantages of the methods.

" Describe briefly the geochemical classification of elements. Add a note on the role of trace elements in magmatic crystallization.

Discuss briefly the 'National Mineral Policy'.

8.
What are the differences between Banded Iron Formation and Ironstone? Why there is minimum/no detritus found in Banded Iron Formation?

Give a brief description of mode of occurrence and distribution in India of Bauxite deposits.

Enumerate the legislative measures in India for environment protection.