Metamorphic Petrology
1.Which of the following is/are characteristic of the process of metamorphism?
a) under normal conditions the bulk chemistry of the rock remains unchanged
b) there is no large-scale liquid at any given time
c) there is no order of crystallization
d) all of the above
2. The main type of chemical reaction involved in the process of metamorphism is
a) Solid à Solid +Vapour
b) Solid +Liquid à Solid +Gas
c) Liquid +Liquid à Solid
d) Liquid +Gas à Solid
3. The thermal or contact metamorphism is characterized by
a) High temperature, low pressure, low strain and variable fluid pressure
b) High temperature, high pressure, low strain and variable fluid pressure
c) High temperature. low pressure, variable strain and variable fluid pressure
d) High temperature, high pressure, high strain and high fluid pressure
4. Which of the following rocks have NOT resulted due to contact metamorphism 7
a) Spotted slates
b) Hornfelses
c) Skarns
d)Augen gneisses
5. Hornfelses generally possess
a) Porphyroblastic fabric
b) Granoblastic fabric
c) A combination of porphyroblastic and granoblastic fabric
d) Foliated fabric
6. Thermal metamorphism of dolomitic limestones with small siliceous impurity leads to the formation of
a) Forsterite marble
b) Brucite marble
c) Serpentine marble
d)Tremolite marble
7. Metamorphism involving substantial addition or removal of materials is generally termed as
a) Contact metamorphism
b) Autometamorphism
c) Metasomatism
d) Pneumatolysis
8. The metamorphism involving the combined effect of uniform pressure and heat is described as
a) Plutonic metamorphism
b) Dynamothermal metamorphism
c) Cataclastic metamorphism
d) Contact metamorphism
9. The development of tectonites is widespread in
a) Dynamothermal metamorphism
b) Plutonic metamorphism
c) Cataclastic metamorphism
d) Pyrometamorphism
10. Which of the following is matched correctly ?
a) Pyrometamorphism-----low temperatures
b) Contact metamorphism-----high temperatures
c) Kinetic metamorphism -----directed pressure predominant
d) Pneumatolysis -----changes due to solution action
11. Choose the correct statement from the following
a) Uniform pressure acts on both liquids and solids
b) Directed pressure causes a change in volume
c) Uniform pressure leads to a change of surface
d) All of the above are correct
12. When uniform or hydrostatic pressure acts on a body, its
a) Volume decreases
b) Specific gravity decreases
c) Volume decreases but specific gravity increases
d) Volume increases but specific gravity decreases
13. Which of the following effects takes place when a body is subjected to directed pressure ?
( i) Dilation
(ii) Distortion
(iii) Formation of unidimensional grains
(iv) Growth of the body in a direction perpendicular to the direction of stress
(v) Solubility of the minerals is decreased
a) (i), (iii), (iv) and (v) only
b) (i), (iii) and (iv) only
c) (ii), (iii), (iv) and (v) only
d) (ii), (iii) and (iv) only
14. Oriented mineral grains and foliated appearance of the rocks is a characteristic feature of the rocks belonging to
a) Epizone
b) Mesozone
c) Katazone
d) Epizone and Katazone
15. Which of the following rocks are completely unfoliated?
a) Slates
b) Schists
c) Phyllites
d) Hornfelses
16. Minerals whose fields of stability on a P-T diagram are extended on the introduction of a non-hydrostatic stress are described as
a) Stress minerals
b) Anti-Stress minerals
c) Elastic minerals
d) Plastic minerals
17. Stress minerals arc characterized by
(i) High packing index of crystal lattice
(ii) Low molar volume
(iii) High density
(iv) Equidimensional habit
a) (i) and (iii) only
b) (i) and (ii) only
c) (i). (ii) and (iii) only
d) (ii), (iii) and (iv) only
18. Which of the following is a stress mineral?
a) Andalusite
b) Sillimanite
c) Kyanite
d)Cordierite
19) Stress minerals are generally absent in
a) Epizone
b) Mesozone
c) Katazone
d) None of the above
20) Minerals which develop their crystal form in spite of the resistance of a solid medium are described as
a) Xenoblastic
b) Idioblastic
c) Crystalloblasti
d)Granoblastic
ANSWERS
1-d 2- a 3- a 4-d 5-c 6- a 7-c 8- a 9-a 10- c 11-a 12- c 13-d 14- b 15-d 16- a 17-c 18- c 19-c 20-b
SEDIMENTARY PETROLOGY
| 1. The smallest megascopic layer in a sedimentary sequence is a a) Bed b) Stratum c) Lamina d) All of the above |
| 2. To be classified as 'laminae', the thickness of each layer should be a) >1 cm b) <1>2cm d) <2cm |
| 3. A bedset consists of two or more superimposed beds that have identical a) Colour b) Composition c) Texture d) Internal structure e) Genesis |
| 4. Alternate deposition of fine and coarse-grained sediment gives rise to a) Torrential bedding b) Cross bedding c) Graded bedding d) Festoon bedding |
| 5. Flaser bedding is a) a ripple bedding in which mud streaks alternate with sand and silt surfaces b) a ripple bedding which shows well-preserved sand lenses embedded within the muddy layers c) a discordant bedding showing lateral gradation d) a concordant bedding showing progressive fining in the upward direction |
| 6. The most common mode of origin for cross-bedding is a) Migration of small and mega-ripples b) Deposition on the point bars of small meanders c) Deposition on the inclined surfaces of beaches d) Lee-side deposition of sand dunes |
| 7. The bundle-wise up building of foreset laminae in a single unit is characteristically seen in a) Longitudinal cross-bedding b) Channel-fill cross-bedding c) Wave-ripple bedding d) Climbing-ripple lamination |
| 8. Aeolian ripples are characterized by the presence of a) Coarser grains on the crests b) Finer grains on the crests c) Uniformly even grains on the crests and the troughs d) None of the above |
| 9. Ripples formed by water and wind differ in their a) Symmetry b) Scale c) Azimuth d) Ripple index |
| 10. Ripple index (R.I.) is 'the wavelength of the ripple divided by its amplitude if the R.I. is greater than 15 it may be presumed that the ripples are formed by the action of a) Water b) Wind c) Waves d) Currents d) Ripple index |
| 11. Horizontal or lateral gradation of material occurs if the deposition takes place in a) Stagnant water b) Running water c) Underground water d) Shore zone |
| 12. In the case of flaser bedding the conditions are more favourable for the deposition and preservation of a) Sand b) Mud c) Both sand and mud d) None of the above |
| 13. Textures in which the fragmental characteristics are NOT clearly visible are described as a) Epiclastic b) Clastic c) Non-clastic d) Pyroclastic |
| 14. The degree of roundness does NOT depend upon a) Size of the particles b) Hardness of the particles c) Specific gravity of the particles d) Degree of transportation |
| 15. Theoretically speaking sphericity and roundness of a grain are (i) Geometrically different and independent properties (ii) Geometrically similar and mutually dependent properties (iii) Related to the size of the clastic particles (iv) Unrelated to the size of the elastic particles a) (i) and (iii) are correct b) (i) and (iv) are correct c) (ii) and (iii) are correct d) (ii) and (iv) are correct |
| 16. In nature roundness varies between a) 0.01 to 0.05 b) 0.05 to 0.1 c) 0.1 to 0.9 d) 1.0 to infinity |
| 17. SORTING may be defined as a) A measure of the spread of grain-size distribution b) A qualitative parameter measuring the departure of a body from equidimensional character c) A measure of the sharpness of the edges and corners of a particle d) None of the above |
| 18. Residual deposits are a) Well sorted and rounded b) Unsorted and angular c) Ill sorted and sub-rounded d) Assorted and well-rounded |
| 19. Sorting of particles is best in a) Fluvial sediments b) Sand dunes c) Beach sediments d) Loess sediments |
| 20. Which of the following is a measure of the symmetry of the distribution of grains? a) Sphericity b) Roundness c) Kurtosis d) Skewness |
GEOLOGY QUESTIONS
1. The primitive crust of the earth was
(a) granitic (b) basaltic
(c) komatiitic (d) andesitic
2. The major source of heat in the primordial earth was
(a) decay of short-lived radioactive isotopes
(b) decay of long-lived radioactive isotopes
(c) impact of planetesimals
(d) all of the above
3. Bedforms with the crest trending roughly parallel to the net sediment transport
direction are called
(a) linear dune
(b) longitudinal dune
(c) seif dune
(d) parabolic dune
4. Transgression is cause by
(a) rise in eustatic sea level
(b) rise in relative sea level
(c) increased rate of subsidence
(d) decreased rate of sedimentation
5. Boudins are products of
(a) homogeneous deformation
(b) inhomogeneous, brittle deformation
(c) inhomogeneous, ductile deformation
(d) none of the above.
6. Temperature at the crust-mantle boundary is of the order of
(a) 600°C
(b) 900°C
(c) 1700°C
(d) 1300°C
7. Diphyodonty does not take place in
(a) incisors
(b) pre-molars
(c) molars
(d) canines
8. Epsilon cross-stratification is common in
(a) marine environment
(b) fluvial environment
(c) lacustrine environment
(d) aeolian environment
9. S- or Z-shaped inclusion trails in garnets indicate
(a) Syn-tectonic crystallization
(b) Pre-tectonic crystallization
(c) Post-tectonic crystallization
(d) None of the above
10. Under high P-T conditions Al is favoured in a SiO4 tetrahedra linkage in the
(a) 4 co-ordinated position
(b) 6 co-ordinated position
(c) 8 co-ordinated position
(d) 10 co-ordinated position
11. Barapasaurus tagorie, a Jurassic dinosaur, was recovered from
(a) Jabalpur Formation
(b) Ariyalur Formation
(c) Kota Formation
(d) Bhuj Formation
12. Paratype is formally designated when
(a) used in the description of the species
(b) a new specimen is used due to the destruction of the type specimen
(c) it is not the part of the original type material
(d) several type specimens are used
13. Foreland basins are associated with
(a) crustal extension
(b) strike slip faults
(c) thrust loading
(d) thermal contraction
14. Transform faults occur within
(a) continental lithosphere
(b) oceanic lithosphere
(c) both continental and oceanic lithosphere
(d) none of the above
15. An area in isostatic equilibrium would show
(a) no free air anomaly but may show Bouguer anomaly
(b) no free air and Bouguer anomaly
(c) free air anomaly but no Bouguer anomaly
(d) none of the above.
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