---
title: "Define landslide and its parts"
subject: "Engineering Geology I"
chapter: 6
key: "semester_3/engineering_geology_i:define-landslide-and-its-parts"
source: https://www.bctengineer.com/q/semester_3/engineering_geology_i/define-landslide-and-its-parts
site: BCT Engineering
---

# Define landslide and its parts

Engineering Geology I · Chapter 6: Physical Geology

- Asked in: 2062 Baisakh (old course), 1+3 marks
- Video: [Introduction to Landslides](https://www.youtube.com/watch?v=gro09PKmQoY) — Kelli's Geology Lair
- Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14
- Page: https://www.bctengineer.com/q/semester_3/engineering_geology_i/define-landslide-and-its-parts
- Whole chapter: https://www.bctengineer.com/md/semester_3/engineering_geology_i/chapter-6

## Question

Define landslide and mention its various parts with illustration.

## Short answer

A landslide is the downward and outward movement of rock, soil or debris along a slip surface under gravity. Its parts include the crown, main scarp, head, slip surface, displaced body, toe, foot and flanks.

## Answer

A **landslide** is the downward and outward movement of slope-forming rock, soil or debris along a slip surface under gravity.

```text
   crown (undisturbed ground)
   ======+
         |  <- main scarp
         +-----+  head
          . . . +--------+
          .  slip surface  +---+
          .  body (moved)   . toe
          . . . . . . . . . .+---> foot
```

Main parts:
1. **Crown:** undisturbed material above the main scarp.
2. **Main scarp:** steep surface at the upper edge, formed by the slide.
3. **Head and minor scarps:** top of the moved mass and small steps within it.
4. **Slip (rupture) surface:** the surface on which movement takes place.
5. **Body (displaced mass):** material above the slip surface.
6. **Toe and foot:** lower margin of the moved mass, and the part beyond the toe of the rupture surface.
7. **Flanks:** the sides of the slide.

## Check yourself

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

1. A landslide is:
   A. Horizontal movement of plates
   B. Wind transport of soil
   C. Downward and outward movement of slope-forming rock, soil or debris along a slip surface under gravity
   D. Settlement of a foundation under load
   Answer: C. Gravity drives movement on a slip surface. (Key point: Definition)

2. The crown of a landslide is:
   A. The lower margin of the moved mass
   B. The surface on which movement occurs
   C. The sides of the slide
   D. Undisturbed material above the main scarp
   Answer: D. The crown lies above the scarp, in intact ground. (Key point: Crown)

3. The slip (rupture) surface is:
   A. The surface on which movement takes place
   B. The steep surface at the upper edge
   C. The part beyond the toe
   D. The top of the moved mass
   Answer: A. The displaced body lies above this surface. (Key point: Slip surface)

4. The toe of a landslide is:
   A. The steep upper edge of the slide
   B. The lower margin of the moved mass
   C. Undisturbed ground at the top
   D. The sides of the slide
   Answer: B. The foot is the part beyond the toe of the rupture surface. (Key point: Toe and foot)

## Related in other subjects

- [Parts of a landslide](https://www.bctengineer.com/question.md?key=semester_4%2Fengineering_geology_ii%3Alandslide-parts-diagram) — Engineering Geology II, chapter 5