1 / 42

The Geosphere

The Geosphere. The Geosphere. The Geosphere is all the rocks , minerals , soils and lanforms of the planet , including all the internal structure of the planet .

rhona-fields
Download Presentation

The Geosphere

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. TheGeosphere

  2. TheGeosphere • TheGeosphereisalltherocks, minerals, soils and lanforms of theplanet, includingalltheinternalstructure of theplanet. • TheGeosphereisalwayschanging and isnot in thesameformnow as itwasmillions of yearsago, and notthesmenow as itwill be in a millionyears

  3. Scientists divide the Earth into three layers based on composition • Crust – the thinnest layer of the Earth (5-20km thick) made entirely of light elements • Mantle – makes up 64% of the earth’s mass, (2900km thick) made of rocks of medium density • Core – has a radius of 3400km and composed of the densest elements

  4. Earth`s layers • Core: iron rich, dense • Mantle: less dense, rocky • Crust: even less dense, rocky. Composed of lighter elements (Oxygen and Silicon)

  5. TheGeosphereismade of rocks • Rocks are made of minerals • Minerals are made of atoms RocksMineralsAtoms

  6. Minerals • naturallyformed, inorganiccrystallinesolids, composedof atomswithspecificchemicalcomposition • notmanufactured in laboratories • Ordered in a geometricpattern • Have a range of compositions • Itisnotmade up of organiccompounds

  7. Minerals • Mineralshavespecificpropertiesdependingonwhatatomsthey are madefrom and whatstructurethey are in • Forexamplediamond and graphite are bothmadefromcarbon, butbecause of thestructurethay are VERY different!

  8. Mineral properties • Are classified by the chemical composition and the crystal structure • Identified by physical properties

  9. IdentifyingMinerals • There are a range of teststoidentifyminerals: • Streak test • Hardness test • Lustre test • Reactionwithacid • Density • Colour

  10. Streak Test • Scratchingthe mineral withglassorwith a streakplatetoseethecolour of thepowder

  11. Hardness • Hardnessis a measure of howdifficultitistoscrath a mineral. • Measuredusingthemohsscale • Scratchingminerals off eachother, you can seewhichoneisharder. • Diamondisthehardest mineral • Calcisthesoftest

  12. Mohs Scale

  13. Lustre • Lustre is a measure of howmuchthe mineral shines (reflect light)

  14. Colour, Density and Acidtests • Whatcolouristhe mineral? • Densitymeasurestherelationbetweenthemassanthevolume of the mineral. Basically “Howmuchstuff (atoms) are in a certainspace • Acidtestsmeasurethereaction of the mineral withacids. Ifthe mineral react, itprobablycontainscalcium carbonate.

  15. Uses of Minerals • Minerals are veryimprotantfortheplanet • Weneedmineralslikecopperand iron in ourbodiestosurvive • Minerals are used to make things from mobile phones and computers to jewellery

  16. Weathering • Weatheringaffectsthestructure of rocks • Weatheringis a slowprocessthathappensover a verylong time • Maintypes of weathering: • Physicalweathering • Chemicalweathering • BiologicalWeathering

  17. PhysicalWeathering • Physicalweatheringiswhenphysicalprocesses break downrocks • Examples: • When ice freezes in the crack of a rock, itexpands and makesthe crack bigger. Ifthisrepeatsthe rock can break • Whenrocksgetveryhottheyexpand. Iftheyexpand and contractrepeatedlythey can breakdownintosmallpieces

  18. ChemicalWeathering • Chemicalweatheringiswhenwaterflowsover rock and dissolvessome of thematerials in the rock. • Thismakestheroskhave a verysmoothform. • Thisishowmineralslikecalcium and magnesiumgetintowater.

  19. BiologicalWeathering • Biologicalweatheringoccurswhen living things break downrocks. • Thiscould be fromplants, orfromthechemicalsexcretedby living organismsslowlybreakingdownthe rock.

  20. Rocks • There are threemaingroups of rock types • SedimentaryRocks • IgneousRocks • MetamorphicRocks

  21. What are Rocks? • A rock is a naturally occurring solid mixture of one or more minerals, or organic matter • Rocks are classified by how they are formed, their composition, and texture • Rocks change over time through the rock cycle

  22. Igneous Rocks • Igneous rock begins as magma under . • Magma can form: • When rock is heated • When pressure is released • When rock changes composition • Magma is a mixture of many minerals http://www.fi.edu/fellows/payton/rocks/create/igneous.htm

  23. Igneous Rocks • Coarse-grained: cools slowly under the surface of the earth, giving mineral crystals more time to grow • Fine-grained: cools quickly on the surface, with little to no crystals

  24. Igneous Rocks Coarse-Grained Fine-Grained Granite Rhyolite Gabbro Basalt

  25. Igneous Rocks • Intrusive Igneous Rocks: magma pushes into surrounding rock below the Earth’s surface • Extrusive Rocks: forms when magma erupts onto the Earth’s surface (lava), cools quickly with very small or no crystals formed http://www.windows.ucar.edu/tour/link=/earth/geology/ig_intrusive.html&edu=high&fr=t

  26. Sedimentary Rocks • Sedimentary rock is formed by erosion • Sediments are moved from one place to another • Sediments are deposited in layers, with the older ones • on the bottom • The layers become compacted and cemented together http://www.fi.edu/fellows/payton/rocks/create/sediment.htm

  27. Sedimentary Rock • Sedimentary Rocks are formed at or near the Earth’s surface • No heat and pressure involved • Strata – layers of rock • Sedimentary rock can • often contain fossils

  28. SedimentaryRocks

  29. Metamorphic Rock • Meaning to change shape • Changes with temperature • and pressure, but remains • solid • Usually takes place deep in • the Earth http://www.fi.edu/fellows/payton/rocks/create/metamorph.htm

  30. Metamorphic Rock • Underheat and pressurethestructure of the rock changes

  31. MetamorphicRocks

  32. The Rock Cycle

  33. Identification of Rocks • Rocks can be identifiedusingthefollowingquestions: • Doesithavelayers? • Doesitcontainlargecrystals? • Isithard? • Doesitcontainfossils? • Whatcolourisit? • Doesitreactwithacid?

  34. Soils • Mixtures of differenttypes of soilsmake up thesoil of theplanet • Maintypes of soil are: • Sandy Soils • Claysoils • LoamSoils • Humus

  35. Sandy soils • Thesecontainlargeparticles, withspacebetweentheparticleswhichallowswatertopassthrougheasily

  36. Sandy Soils

  37. ClaySoils • Claysoils are made of smallparticleswithverylittlespacebetweenthem. Thismeansitisdifficultforwatertofilterthroughthesoil

  38. Loamsoils • Loamsoils are a combination of sandysoilsand clayeysoils.

  39. Humus • Humus isthethinlayercontaininglots of organicmatter, itisusuallyfoundonthesurface of soils

  40. FossilFuels • Gas and oil are formedfrom living sea creaturesthatfalltothebottom of the sea. Over time they are buriedunderlayers of sediment and thebiochemicals in theirbodiesreacttoform gas and oil. • Coal ismadefrom living plantsthatdiedbillions of yearsago, werecovered in layers of sediment and reacted in theabsence of oxygentoformcoal

More Related