M.Sc. (Semester (CBCS) Examination Mar/Apr-2018
Applied Geology
GEOCHEMISTRY
Time: 2½ Hours
Max. Marks: 70
Instructions: Answers any five questions. All questions carry equal marks. Question 1 is compulsory. Answer any two essay questions from Q.2, 3 4. Answer any two short notes questions from Q.5, 6 7. Draw neat and labeled diagrams wherever necessary.
Q.1
Choose the correct answer:-
14
Siderites consist essentially
Nickel-iron alloy
Nickel-iron alloy and silicates
Silicates only
Silicates and graphite's
The diffused layer within the stratosphere that plays a vital part in absorbing ultraviolet radiation is
Tropopause
Ozonosphere
Ionosphere
None
The evolution of the atmosphere is on the aspect
Primeval atmosphere
Additional during geological time

Losses during geological time
All the above
Which of the thermonuclear process reaction is responsible for the evolution of elements 28 to A=57 at the Fe peak?
Hydrogen burning
Helium burning
Silicon burning
None
Clarke and Washington (1924) estimated the
Dispersed elements in the earth's crust
Average percentage of an element in the earth's crust
Distribution of a particular element between two phases
Bulk composition of earth
Who has introduced the term siderophile, chalcophile, lithophile and atmophile
Goldschmidt (1923)
Clarke (1924)
Ringwood (1975)
Cameron (1937)
The geochemical character of an element is largely governed by the
Number of proton in the nucleus
Number of neutrons in the nucleus
Electronic configuration of its atoms
All the above
The average chemical composition based on 5159 superior analysis is for
Granite
Sandstone
Gneisses
None
Page 2 of 2
SLR-UB-31
Distribution of elements in the earth is controlled by
Atomic weight
Electronic configuration
O
r/z index
All of the above
10) Which of the radiogenic element has half life of 5730 years?
235 U
234U
14C
16 O
11) Different elements with the same neutron number but with different values of atomic weight and protons are known as
Isotopes
Isobars
Isotones
Isotherm
12) The composition of upper mantle is
Granitic composition
Basic composition
Ultrabasic composition
Felsic composition
13) The upper crust of the earth consists mainly of:
Standstone
Shales
Limestones
Igneous and metamorphic rocks
14) Chlorinity is determine by precipitation of halides with
HCl
HClO4
AgNO3
NaOH
Q.2
Describe the physico-chemical factors involved in formation of soil. Add note on soil profile.
14
Q.3
What is radioactivity? Explain in brief different radioactive techniques.
14
Q.4
Discuss the composition of atmosphere and add a note on gain and loses during evolution of atmosphere.
14
Q.5
Write short notes on the following:-
14
Cosmic abundance of elements
Average composition of igneous rocks
Q.6
Write in brief on the following:-
14
Eh-pH Diagram
Chalcophile
Q.7
Explain in short the following:-
14
Zonal structure of Earth
Geochemical cycle