Year 9 Changing Earth - Extra Stuff
Science as a Human Endeavour
Science Investigations
Reading Resilience
Extenshun
Volcanic Ash and Airlines
Measuring the Speed of Tectonic Plates
Development of the Geological Timescale
Earthquake-proofing Buildings
Supercontinents
Volcano Exploration Robots
Subduction Zones and Ophiolite Belts
Supervolcanoes
Historic Earthquakes
Magnetic Striping Simulation
Mantle Convection Simulation
Build a Model Volcano
Hotspot Simulation
Build a Seismometer
Build a Geological Timescale
Copy across from Year 8 Rocks
References
Lake Taupo
Lake Toba
Yellowstone
Ancient supervolcanoes along the Cosgrove hotspot track
Pioneered in NZ!
Iceland eruption of 2010
Exploring the effects of ash on machinery and living things
What is ash?
Effects on planes
Effects on people
How was it handled?
What happened?
How is it done?
Lasers
Satellites
Applications
How was it done?
Radiometric dating (absolute)
Divisions of the timescale
Eons (e.g. Proterozoic)
Eras (e.g. Cenozoic)
Periods (e.g. Quaternary)
Epochs (e.g. Holocene)
Mention the 'Anthropocene' and the theory that humans are beginning to affect the world's geology!
How do we know what ancient supercontinents looked like?
Mapping using fossil distributions
Mesosaurus fossils have been found on both sides of the Atlantic, helping to reconstruct Gondwanaland
Trilobite fossils have been used to mark out the boundaries of ancient
continents - could refer to Richard Fortey's book!
Mapping using glacial evidence
History of Pangaea
Earlier supercontinents
Ur
Rodinia
Hypothesised by Wegener
All major landmasses joined together during the Carboniferous Period
Widespread rifting took place as Pangaea began to break apart in the Triassic Period
'Pangaea' = 'all lands'
Part of his continental drift theory
Formation and breakup explained by plate tectonics
Link back to relevant Science Understanding lessons
Existed during the 'Snowball Earth' period
Earliest known supercontinent; formed around 3.6 billion years ago
Anatomy of a subduction zone
Accretionary wedge
Island arc
Assume oceanic crust subducts under continental crust
Layers of oceanic crust correspond to layers in an ophiolite belt
Ophiolite case studies
NZ - Dun Mountain Belt
Cyprus - Troodos Ophiolite
Dunite (olivine-rich rock) characteristic of this belt
Associated with economic deposits of copper
How subduction happens
Also pioneered in NZ!
References
'A Continent on the Move' page 13
Known ophiolites formed at times of supercontinent break-up when widespread subduction took place
Where'd the cool names come from?
Relative dating
Rock strata
Fossils
Forams
Radiolaria
Ammonites
Vertebrates - dinosaurs, mammoths, cool junk
Early divisions: Primary, Secondary, Tertiary, Quaternary
Valdivia - 1960
Japan - 2011
Newcastle (NSW) - 1989
Highest Richter magnitude ever recorded (9.5)
Generated a massive tsunami
Thought to have ejected 2800 km^3 of magma!
Associated with the breakup of Gondwana
Threw material (including zircons) all the way from northern Queensland to WA!
Known to have generated pumice, ignimbrite and pyroclastic flows
Contained around 530 km^3 of magma
History of exploring volcanoes
Use quotes from NASA article
Spotlight on Carolyn Parcheta, postdoctoral fellow based at NASA's Jet Propulsion Lab
What have we learned so far?
What do scientists hope to achieve with these robots?
Records of Mt Vesuvius eruption in 79 AD
Finding volcanoes on the ocean floor
Volcanoes in spaaaaaaace!
Why use robots?