University:
McMaster University
Course:
EARTHSC 1G03 | Earth and the Environment
Academic year:

2023
Views:

392

Pages:

2
Author:

Sabrina S.

Part 2: Shaping the Surface - Class Notes ● This lecture, we explored various processes that shape the Earth's surface. Weathering: is the disintegration of rocks, soil and minerals through the agencies of the Earth’s atmosphere. It occurs in two main forms:It occurs in two main forms: 1. Mechanical Weathering: The process of ruining rocks into smaller particles but the chemical composition of particles remains the same. 2. Chemical Weathering: A chemical process through which rocks are disintegrated or decomposed by chemical action which may include action with water to produce new minerals. **Rock Cycle (Important)** FIG1 Erosion : The act of erosion entails the transportation of disintegrated material from one area to another. Major agents of erosion include: 1. Water: Flooding water bodies namely rivers, rain, and ocean waves help transport the particles away. 2. Wind: Transports sand and dust over very large distances. 3. Ice: They abrade and transport relatively massive portions of the Earth’s lithosphere. Deposition is the process by which eroded material is abandoned, or dropped off at a new location. This can form various geological features such as: ● ● ● Deltas: Developed out of sedimentation of the deposits at the delta of a river. Sand Dunes: Formed by wind to blow sand in hillocks and dunes. Moraines: Landforms created by the disposal of-genetic debris by glaciers. Mass-wasting therefore entails any form of downward movement of rock and soil due to the force of gravity. - Landslides: Transportation of a huge volume of earth material from one position to the other in the shortest time possible on a slope. - Slumps: Less faster and in circular manner the soil and rock material move. Rockfalls: Occurrences of rock falls on steep slopes or cliffs that involve free fall of the rocks. Human Impact - Another form of processes includes the effects due to human activities that also influence the surface of the Earth. Key activities include: 1. Deforestation: That was seen especially when destructing trees, since this process leads to changes in the topography and causes the rate of erosion to rise. 2. Urbanization: Constructing and developing modify the face of the earth in terms of the natural geographic features that it possesses. 3. Agriculture: This advent of farming also poses challenges whereby; farming techniques may contribute to soil erosion and degradation.