Review: landforms, volcanoes and rocks
Moving water, wind, ice and gravity shape the Earth’s surface, and so do volcanoes. Deposition lays sediment in layers and builds deltas, sandbars and dunes. A canyon is a deep, steep-sided landform that a river cuts over a very long time, while a valley is wider with gentle slopes. A delta forms where a fast river slows at the sea. Wind builds dunes behind obstacles. Rock layers have the oldest at the bottom, and fossils such as those in Wadi Al-Hitan show that a sea once covered the land. The crust is broken into tectonic plates, and volcanoes cluster along their edges. Magma that reaches the surface is lava. In the rock cycle, igneous, sedimentary and metamorphic rock change into each other. Scientists watch warning signs and people prepare plans to stay safe.
| Landform or event | Main cause |
|---|---|
| canyon | a river eroding rock for a very long time |
| delta | deposition where a river meets the sea |
| dune | wind dropping sand |
| volcano | magma rising near plate edges |
| Layer | Position | Age |
|---|---|---|
| A | top | newest |
| B | second | in between |
| C | third | in between |
| D | bottom | oldest |
Term 2 in one page. Fold a page into four parts. In each part draw and label one of these: a canyon with a river, a delta, a layered cliff with an oldest and a newest layer, the rock cycle. Under each write one sentence using a Term 2 word. Show the page to someone at home and explain your favourite part.