The Crust makes up less than 1% of the Earth’s mass (0.4%) It is made of oxygen, magnesium aluminum, silicon calcium, sodium potassium, iron. There are 8 elements that make up 99% of the Earth’s crust. The continents are about 35 km thick and the ocean floors are about 7 lm thick.
The Mantle is the solid casing of the Earth and is about 2900 km thick. It makes up about 70% of the Earth’s mass (68.1%). It is made up of silicon, oxygen, aluminum and iron.
The Core is mainly made of iron and nickel and makes up about 30% of the Earth’s mass (31.5%). The Outer Core is 2200 km thick and is liquid and the Inner core is 1270 km thick and is solid.
Minerals: all rocks are made of one or more of the 3000 known minerals.
Rocks: made of 2 or more minerals.
Igneous rocks: Form when molten lava (magma) cools and turns to solid rock. The magma comes from the Earth’s core which is molten rock. The core makes up about 30% of the Total Earth Mass (31.5%) There are 5 kinds of igneous rocks, depending on the mix of minerals in the rocks. Granite contains quartz, feldspar & mica. Diorite contains feldspar & one or more dark mineral. Feldspar is dominant. Gabbro contains feldspar & one or more dark mineral. The dark minerals are dominant. Periodotite contains iron and is black or dark. Pegmatite is a coarse-grained granite with large crystals of quartz, feldspar and mica. Obsidian is nature’s glass. It forms when lava cools quickly on the surface. It is glassy and smooth. Pumice is full of air pockets that were trapped when the lava cooled when it frothed out onto the surface. It is the only rock that floats.
Sedimentary Rocks: Cover 75% of the earth’s surface. Most of the rocks found on the Earth’s surface is sedimentary even though sedimentary rocks only make up less than 5% of all the rocks that make up Earth. When rocks are exposed to the elements – air, rain, sun, freeze/thaw cycle, plants – erosion occurs and the little bits of rock worn away get deposited as sediments. Over time, these sediments harden as they get buried by more sediments and turn into sedimentary rocks. Sedimentary rocks are usually formed in layers (strata). There are 6 main kinds of sedimentary rocks depending on the appearance of the rock. Conglomerate rock has rounded rocks (pebbles, boulders) cemented together in a matrix. Sandstone is a soft stone that is made when sand grains cement together. Sometimes the sandstone is deposited in layers of different coloured sand. Shale is clay that has been hardened and turned into rock. It often breaks apart in large flat sections. Limestone is a rock that contains many fossils and is made of calcium carbonate &/or microscopic shells. Gypsum, common salt or Epsom salt is found where seawater precipitates the salt as the water evaporates. Porphyry rock is when jagged bits of rock are cemented together in a matrix.
Metamorphic Rocks: The least common of the 3 kinds of rocks. Metamorphic rocks are igneous or sedimentary rocks that have been transformed by great heat or pressure. Foliated metamorphic rocks have layers, or banding.
Slate is transformed shale. It splits into smooth slabs. Schist is the most common metamorphic rock. Mica is the most common mineral. Gneiss has a streaky look because of alternating layers of minerals. Non-foliated metamorphic rocks are not layered.
Marble is transformed limestone. Quartzite is very hard.
Sedimentary rocks: sandstone, limestone, conglomerate and breccia, mangane modules, calk, flint, coal
Metamorphic rocks: metaquartzite, marble, slate, eclogite.
Minerals: Halite, beryl,gold, silver, quartz, amethyst, feldspar, mica, augite, hornblende, olivine, galena and cassiterite, bauxite, tourmaline, opal, geode, agate, fool's gold(something that looks like gold), gymsum, calcite, rhodochrosite, barite, celestite, kyanite, garnet, malachite, azurite, fluorite, zeolite, amber, sapphire and ruby, diamond, jade (nephrite or jadeite).
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