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Types of Mountains: Fold Mountains - Simple Notes Fold Mountains - Most Common & Important: These are the most widespread and most important type of mountain. How Fold Mountains are Formed: Large-scale Earth Movements: Created by massive forces within the Earth. Stresses in Earth's Crust: These forces cause stress in the Earth's outer layer (crust). Causes of Stress: Stress can come from: Weight of rocks above. Movement of hot rock in the Mantle (below the crust). Magma (molten rock) pushing into the crust. Expansion or shrinking of parts of the Earth. Compressive Forces: These stresses lead to pushing or squeezing forces (compression) on rocks. Folding and Wrinkling: Rocks are forced to fold and wrinkle along weak areas. Think of pushing a tablecloth from the sides - it wrinkles up! (See Fig. 18 a & b in your text). Upfolds and Dow...

Earth Movements and Major Landforms Earth's Face is Always Changing: The Earth's surface is constantly being reshaped . Two Main Forces Shaping Land: Denudation Agents (Wearing Down): These are forces that wear away the land: Running water (rivers) Rain Frost (ice) Sun Wind Glaciers (large ice rivers) Waves (ocean) Think of them as sculptors slowly carving away at the Earth. Earth's Crust Movements (Building Up): Movements inside the Earth that create mountains, plateaus, and plains. These movements make the basic shape of the land. Denudation agents then modify these shapes. Orogenic Movements = Mountain Building: "Orogenic" means related to mountain formation. Earth has had many mountain-building periods throughout history. Text mentions nine orogenic movements in geological time! These movements fold and fr...

Influence of Rock Types on Landscape (Using West Malaysia as an Example) The type of rock underlying a region plays a key role in shaping its landscape. Harder rocks resist erosion and form highlands, while softer rocks wear away faster, creating lowlands. Here’s how different rocks shape West Malaysia’s terrain: 1. Resistant Igneous & Metamorphic Rocks Granite : Forms the  Main Range  and  Eastern Range  (peaks over 2,000 feet). Creates  smooth slopes  and  rounded hilltops  due to slow weathering. Quartzite  (metamorphosed sandstone): Extremely hard; forms  Gunong Tahan  (7,186 ft), the highest peak in West Malaysia. 2. Less Resistant Sedimentary Rocks Shale, Schist, Sandstone : Softer and erode faster, forming  lower, rounded hills . Example: Rolling hills in areas with shale/sandstone. 3. Limestone Permeable but Resis...

Metamorphic Rocks Explained Simply Metamorphic rocks form when existing rocks (igneous or sedimentary) are transformed by  intense heat and pressure , often during events like mountain-building or tectonic plate collisions. These forces change the rock’s texture, structure, or mineral composition  without melting it . How They Form Heat : From deep Earth or nearby magma. Pressure : From overlying rocks or tectonic forces. Common Examples Original Rock Metamorphic Rock Clay/Shale Slate Limestone Marble Sandstone Quartzite Granite Gneiss Shale Schist Coal Graphite Key Features Foliated : Layered/banded (e.g., slate, schist, gneiss). Non-foliated : No layers (e.g., marble, quartzite). Why They Matter Used in construction (marble for statues, quar...