BGYCT-135 · December 2022 · English
IGNOU BGYCT-135 December 2022 Previous Year Question Paper
PETROLOGY
Structured previous year question paper for BGYCT-135, December 2022 session.
Max marks: 50 · Questions: 4
Verified: 10 Aug 2026
BACHELOR OF SCIENCE (GENERAL)
(BSCG)
Term-End Examination
December, 2022
BGYCT-135 : PETROLOGY
Time : 2 hours Maximum Marks : 50
Note: All questions are compulsory. Marks allotted
for each question are indicated against it. Draw
well-labelled diagrams, wherever required.
Q1.Briefly answer any five questions of the following : 5x2=10
(a) Define metamorphism.
(b) What are meteorites ?
(c) Distinguish between silica oversaturated and silica undersaturated igneous rocks.
(d) List the processes of magmatic differentiation involved in fluid state of magma.
(e) Give the petrographic significance of Ab-An System.
(f) List four felsic rocks.
(g) What is uralitisation ?
(h) Define lithification. (@) What is heat flow ? G) Write about evaporites.
Q2.Write short notes on any four of the following : 4x5=20
(a) Regional Metamorphism
(b) Uses of Rocks
(c) Poikilitic texture
(d) Colour Index
(e) Physical properties of Magma
(f) — Sorting
(g) | Low-temperature limit of metamorphism
(h) —Cross-bedding
Q3.Answer any one of the following : 1x10=10
(a) Discuss briefly the structures found in igneous rocks.
(b) Briefly describe the common types of sedimentary rocks.
Q4.(a) Explain the importance of studying sedimentary rocks. 5
(b) Discuss the types of processes involved in physical weathering. 5
(a) Discuss the factors affecting textures found in metamorphic rocks. 5
(b) Explain the chemical structures found in sedimentary rocks.