13.07.2015 Views

The planet we live on: The beginnings of the Earth Sciences

The planet we live on: The beginnings of the Earth Sciences

The planet we live on: The beginnings of the Earth Sciences

SHOW MORE
SHOW LESS
  • No tags were found...

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

Geophysical survey Using <strong>the</strong> methods <strong>of</strong> physics to probe <strong>the</strong> <strong>Earth</strong> including: seismology,gravity, electrical methods, magnetic methods and radioactivityGeotechnical engineering <str<strong>on</strong>g>The</str<strong>on</strong>g> study <strong>of</strong> building foundati<strong>on</strong>s and <strong>the</strong> soil/bedrock inwhich c<strong>on</strong>structi<strong>on</strong>s, such as dams, bridges, roads, railways and waterways are sited,toge<strong>the</strong>r with landfill and coastal protecti<strong>on</strong> sitesGeotextiles (ge<strong>of</strong>abrics) Tough textiles used to cover steep slopes to reduce erosi<strong>on</strong>Glacial period (glaciati<strong>on</strong>) A time when <strong>the</strong>re <str<strong>on</strong>g>we</str<strong>on</strong>g>re extensive ice sheets <strong>on</strong> <strong>Earth</strong>Glacial till Sedimentary deposit formed largely <strong>of</strong> mixed mud and boulders, depositedby melting iceGneiss A metamorphic rock formed by high-grade regi<strong>on</strong>al metamorphism; c<strong>on</strong>tainsmetamorphic banding, which sometimes has complex foldingGold (native gold) A mineral made <strong>of</strong> <strong>on</strong>e element (Au) that can be found in mineralveins or eroded from veins and deposited in sedimentsG<strong>on</strong>dwana A ‘superc<strong>on</strong>tinent’ <strong>of</strong> all <strong>the</strong> current sou<strong>the</strong>rn hemisphere c<strong>on</strong>tinents (andIndia) formed around 550 milli<strong>on</strong> years agoGraded bed A layer <strong>of</strong> sediment that is coarser at <strong>the</strong> bottom and becomes finer upwards;frequently deposited by turbidity currentsGranite A coarse-grained, pale-coloured, silica-rich igneous rockGraptolite Extinct animals that formed small col<strong>on</strong>ies strung toge<strong>the</strong>r in saw-blade-likeshapes; <str<strong>on</strong>g>live</str<strong>on</strong>g>d in <strong>the</strong> open oceanGreenhouse effect <str<strong>on</strong>g>The</str<strong>on</strong>g> sun’s radiati<strong>on</strong> absorbed by <strong>the</strong> <strong>Earth</strong>’s surface is re-radiatedas infra-red radiati<strong>on</strong> (heat) that is absorbed by ‘greenhouse gases’ such as carb<strong>on</strong>dioxide and methane, causing <strong>the</strong> surface <strong>of</strong> <strong>the</strong> <str<strong>on</strong>g>planet</str<strong>on</strong>g> to be warmer than it o<strong>the</strong>rwisewould be; <strong>the</strong> gases behave ra<strong>the</strong>r like <strong>the</strong> panes <strong>of</strong> glass in a greenhouse‘trapping’ <strong>the</strong> heatGreenhouse gas A gas in <strong>the</strong> atmosphere that absorbs infra-red radiati<strong>on</strong> (heat); includescarb<strong>on</strong> dioxide, methane and water vapourHalite A mineral, NaCl, white or pink, cube-shaped crystals, good cleavage, low hardness(very s<strong>of</strong>t), soluble in water, forms rock salt depositsHard parts <str<strong>on</strong>g>The</str<strong>on</strong>g> solid parts <strong>of</strong> organisms, such as shells, b<strong>on</strong>es, teeth or cartilage, whichare most likely to become fossilisedHardness (mineral) Usually measured by <strong>the</strong> scratch test, harder minerals will scratchs<strong>of</strong>ter <strong>on</strong>es; Mohs’ scale <strong>of</strong> hardness ranges from 1 (very s<strong>of</strong>t talc) to ten (very harddiam<strong>on</strong>d)158

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!