Planet Earth Review 2 Crust Mantle Core Major Layers of Earth o Relative depth Crust 40 km Mantle 2891 km Core 6370 km o Relative thickness Crust 35 40 km Mantle 2 885 km Core o Mineral and chemical composition Crust Made up of oceanic and continental crust Very heterogeneous Thinnest part Mantle has several parts to it not very heterogeneous Thickest part Core increase in heat towards the core Also increased pressure as you go from the surface to the center of the earth 99 iron very because of residual and radioactive minerals undergoing decay NSCLI Features that we use to determine whether or not something is a mineral o Natural all minerals are naturally occurring substances Found in nature not made by humans o Solid all minerals have to exist in a solid state o Crystal all minerals have a predictable morphology a predictable shape crystal of the minerals is its shape o Lattice the atomic arrangements of the mineral The network in which individual atoms are bonded together o Inorganic its not part of the biological world Meaning that it is not biotic in origin It is still natural however it comes from the inorganic part of nature The three different types of bonds that were discussed in class o Ionic bond 1 atom is negative and 1 atom is positive Loose or gains electrons to become stable Opposites attract The more electrons you have the more negative the atom will be The more electrons you take away the more positive the atom will be o Covalent bond sharing of outer electrons No charged at all o Metallic bond sharing electrons to become stable Ability to conduct electricity heat and malleability Only occur when you re talking about metals Electrons are constantly changing from nuclei to nuclei o Know example of a mineral that is associated with each type of bond Ionic bond Halite rock salt atom of sodium metal and atom of chlorine gas Sodium looses electron to become more positive chlorine gains electron to become more negative Covalent bond silicate minerals minerals made up mostly from the element silicone Covalent bonding of silicone and water creates SiO4 silicone tetrahedron 4 oxygen for every 1 silicone results in a lot of oxygen in the earth Isolated tetrahedron independent tetrahera tetrahedral share no oxygen No tetrahedral are connected ex olivine Metallic bond copper iron silver gold etc Silicate minerals why is something classified as a silicate mineral o Make up over 95 of the continental crust most common minerals on the Earth o 4 oxygen atoms surrounding 1 silicon atom defines the corners of a tetrahedron a pyramid like shape with four triangular faces silica tetrahedron o Different types can be distinguished based on the way in which silica tetrahedron are arranged some can have no oxygen atoms shared and some can have all oxygen atoms shared o Quartz feldspar olivine pyroxene Quartz contains only silicon and oxygen Feldspar contains aluminum which substitutes for silicon in the tetrahedral as well as calcium sodium and potassium Olivine small green crystals without a definitive shape Pyroxene a group of black or dark green minerals that occur in elongate crystals with two cleavage directions at 90 degrees to one another o What type of tetrahedron is associated with each mineral listed above Quartz framework silicates each tetrahedron shares all four oxygen atoms with its neighbors forming a three dimensional structure Feldspar framework silicates Olivine independent tetrahedral no oxygen atoms are shared Pyroxene single chain tetrahedral link to form a chain by sharing Peridotite what is it where is if found what is it made of two oxygen atoms o Ultramafic rock with large grains o Found in the mantle o The most abundant rock on our planet o Made up of isolated tetrahedron olivine and rich in calcium Rocks Rock Cycle What is the rock cycle the succession of events that results in the transformation of Earth materials from one rock type to another then another and so on o Three major rock types Sedimentary rock igneous rock metamorphic rock Formational history Sedimentary rock rock that forms by the movement of particles due to water wind ice and gravity Igneous rock forms through the solidification of molten rock liquid rock magma or lava magma is below the surface of the Earth lava is above Metamorphic rock transformation of rock because of heat pressure Destruction history Sedimentary rock Igneous rock Metamorphic rock cemented minerals Sediment loose grains of minerals Sandstone sedimentary rock o Composition What is a rock a coherent naturally occurring solid consisting of an aggregate of Many grains of quartz and feldspar o Formational history Formed by compaction and cementation Granite more or less the same as sandstones from a mineral perspective but granite has a vastly different formation history o Composition o Formational history also has many grains of quartz and feldspar Quartz and feldspar are formed through erosion Volcanism volcanic rock What types of plate settings are associated with volcanism o Continent to ocean ocean to ocean creates volcanic rock though subduction o Divergent boundaries midocean ridges volcanic activities in these areas caused by seafloor spreading o Continent to continent convergence does not create volcanic rock o Arc volcano continent to ocean or ocean to ocean convergence Architectural parts of a volcano o Crater a circular depression at the top of a volcanic mound through which the vent extrudes o Vent the path that gases and rock travel through Summit central vent Flank vent sides of the volcano o Magma chamber a space below ground filled with magma source of molten rock and agitation also contains gases Mafic versus felsic Bowen s reactions series the sequence in which different silicate minerals crystallize during the progressive cooling of a melt o Volcano type Eruptive style the character of a particular volcanic eruption geologists name styles based on typical examples o Mafic minerals rocks cool from very hot molten rock Therefore parent magmas must be super hot 1 300 degrees C Super hot liquids are runny and easily extruded as lavas o Felsic minerals rocks cool from very cool molten rock Therefore parent magmas must be super cool 700 degrees C Super cool liquids are rigid and do not flow easily o Example of felsic and mafic rocks Felsic rock lighter pinkish Mafic rock blackish greyish greenish o Example of felsic and mafic minerals Felsic minerals quartz and feldspar framework tetrahedrons Mafic minerals