---
title: "Short note: Conglomerate"
subject: "Engineering Geology I"
chapter: 4
key: "semester_3/engineering_geology_i:short-note-conglomerate"
source: https://www.bctengineer.com/q/semester_3/engineering_geology_i/short-note-conglomerate
site: BCT Engineering
---

# Short note: Conglomerate

Engineering Geology I · Chapter 4: Petrology

- Asked in: 2068 Chaitra, 1 marks
- Video: [Conglomerate (geology)](https://www.youtube.com/watch?v=sTKQANhWGVU) — Audiopedia
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_3/engineering_geology_i/short-note-conglomerate
- Whole chapter: https://www.bctengineer.com/md/semester_3/engineering_geology_i/chapter-4

## Question

Write a short note on conglomerate.

## Answer

**Conglomerate** is a coarse clastic (rudaceous) sedimentary rock made of rounded pebbles, cobbles and gravel (>2 mm) cemented in a finer matrix of sand, silt or clay by silica, calcite or iron oxide. The rounded fragments show transport by water. It is bedded and poorly sorted. Strength depends on the cement: siliceous cement is strong, clayey cement is weak. Being porous and weakly cemented in some cases, it can leak and be unstable. It is used as aggregate and in rough masonry, and is common in the Siwalik Zone of Nepal.

## Check yourself

The answer's key points as multiple-choice questions, with the correct option and why.

1. Conglomerate is which type of rock?
   A. Fine clastic igneous
   B. Foliated metamorphic
   C. Pyroclastic igneous
   D. Coarse clastic sedimentary (rudaceous)
   Answer: D. It is made of rounded pebbles and gravel cemented in finer matrix. (Key point: Conglomerate classification)

2. What do the rounded fragments in conglomerate indicate?
   A. Transport by water
   B. Volcanic ejection
   C. Crushing in a fault
   D. Slow cooling of magma
   Answer: A. Rounding results from abrasion during water transport. (Key point: Fragment shape)

3. What controls the strength of conglomerate?
   A. Its colour
   B. The cement: siliceous strong, clayey weak
   C. Its foliation
   D. Its mica content
   Answer: B. Cement type determines strength. (Key point: Strength)