Yr 8 Science
Weathering and rocks
-Rocks and stones are naturally occurring solids that are made of minerals.
-The earths crust is made of rock.
-There are three different types of rock based on the way they form, ignous, sedimentary and metamorphic.
-Rocks have been used by humans for millions of years.
The harder the stone the more compressed the particles. All the atoms link together in a pattern called a lattice that is difficult to pull apart. Some stone is strong, elegantly shaped, beautifully coloured, contains raw materials such as metals and some is rough like pumice which is used to remove hard skin. Earth is 4600m years old. We think of mountains, rivers and sea as things that never change. But over time there have been big changes. Rocks: Conglomerates, Sandstone, Limestone, chalk, Mudstone, Slate, Marble, Granite, Gabbro, Pumice, obsidian.Valleys of rocks are created by glacier. Odd rock forms are caused by strong wind. Rain water is weak acid, the caves and caverns on moorland are caused by the dissolved carbon dioxide in the rain.
Continental Drift is the gradual movement of the continents across the earth's surface through geological time.
- When magma/lava solidifies it forms igneous rock.
- Layers at the bottom of lakes and oceans form sedimentary rocks.
- Sedimentary rocks are sandstone, mudstone, flint, greywacke and chalk.
- Extreme pressure and heat over time forms metamorphic rocks. Metamorphic rocks are marble, quartzite, schist, granulite and slate
- The metamorphic marble is formed from the sedimentary limestone.
- The metamorphic granulite is formed from the igneous basalt.
Rocks like Mt Everest in the Himalayas are used as obstacles by some and admiration objects by others. This proves that rocks are attractions for many types of people. Rocks can be used as tools or to build buildings etc. All rocks have their uses, from fuels to fancy hotels and from beaches to the moorland.
Thanks to nature, the seawater has eroded and shaped many shore side stones, this means rocks are also a form of entertainment. There are even events for stone skimming champions.
This rock above is in a deserted area in America, the cause of its shape is mainly high force winds, the wind eroded the rock and formed this shape.
BY SAM STROUD and Jack Randle
Suggestions from Archie Hill