Landforms

LANDFORMS:
A landform is a feature on the surface of a terrain, natural landforms usually form and change very gradually; some can take millions of years:
UNDERWATER:
1- mid-ocean ridge 2- abyssal plain
3- oceanic trench 4- continental slope 5- continental shelf
RELATED TO
HIGH ALTITUDE: 1-mountain 2-mountain range 3- mountain system 4- glacier
5- plateau
6- (hill)
COASTAL:
1- cape
2- gulf
3- bay
4- peninsula
5- delta
6-river mouth 7- cli�
8- island
9- coast
RELATED TO LOW ALTITUDE:
1- plain
2- flood plain
3- coastal plain 4- valley
5- fluvial valley
6- depression 7- (hill)

1- mid-ocean ridge: an underwater mountain in the middle of the ocean.
2- abyssal plain: an area of flat seafloor at a depth of 4.000 meters
3- oceanic trench: large depression on the seafloor near a continent.
4- continental slope: a steep slope which separates the end of the continental shelf from the oceanic floor.
5- continental shelf: a sloping plain which joins the continents to the seabed, it’s part of the continental crust but it is beneath the sea water.
6- cape: a large piece of land sticking out into the sea.
7- gulf: large area of sea between two capes.
8- bay: is smaller than gulf and the entrance is more closed o�.
9- peninsula: area of land almost completely surrounded by sea, it is only connected to the mainland by a narrow strip of land.
10- Delta: a body of sediment deposited at the mouth of a river.
11- cli�: a high, steep area of rock which suddenly meets the sea.
12- island: is a piece of land surrounded by sea.
13- coast: land close to the sea.
14- mountain: natural elevation of land very high.
15- mountain range: part of a mountain system.
16- mountain system: group of mountains that are related.

17- glacier: create U-shaped valleys
18- plateau: flat landform that is elevated above the sea level 19- hill: natural elevation not very high
20- plain: flat land near a river or near the coast.
21- valley: depression between upland areas, like mountains. Are always formed by the force of water, either as a liquid or solid
22- fluvial valley: has V-shape
23- depression: area of land that is lower than the area around it.

THE MOST IMPORTANT LANDFORMS IN EACH CONTINENTS:
Mountains, plateaus and plains.
GEOLOGICAL STAGES:
The Earth’s surface is constantly changing. During these changes and evolution, we can identify di�erent geological stages.
• Precambrian time (4500 to 542 mya). The first mountain ranges formed. Erosion destroyed them. • Palaeozoic Era (542 to 250 mya). New mountain ranges composed of hard materials formed.
• Mesozoic Era (250 to 65 mya). The sea covered dry land and there was intense sedimentation.
• Cenozoic Era (66 mya) is divided into three Periods: – Paleogene Period (66 to 23 mya). Tectonic plate movement and alpine orogeny occurred. This formed young mountain ranges, such as the Alps.
– Neogene Period (23 to 2.58 mya). Continental movements occurred, most importantly between North and South America.
– Quaternary Period (2.58 mya to present). There were periods of glaciation when ice covered a large part of the continents. This caused intense erosion in mountain areas.