Fragile system learning goals
1. Explain what density is, & how it relates to stratiﬁcation.
Density is mass over volume and it relates to stratification because density is how much mass
fits into a space and stratification is layering which is affected by density because stratification
basically says that less dense materials float on top of denser materials.
2. Explain why disaster scales are based on the Orderof-Magnitude concept, and interpret graphs
with logarithmic scales.
It makes graphs easier to read and allows the graphs to be read in consideration to a larger
range of points since the graph is able to exponentially increase/decrease.
3. Relate natural-disaster risk & intensity to frequency, return period, and consequences (costs).
More intense disasters occur less frequently. Risk is the probably severity that a destructive
event will occur multiplied by the events likely impact on people and property. Consequences
are the negative after effects of a natural disaster on people/property and the return period the
how long on average it takes for the natural disaster to occur again.
4. Explain how recent disasters were associated with the concentration or dilution of energy.
Concentration of energy is when natural disasters take more take to build up then to release, sp
energy is concentrated and the released abruptly ( hurricanes: Months to Days, Earthquakes:
years to minutes, Storms: hours to minutes, Volcanoes: decades to days) Dilution of energy is
when energy is not build up but released over a long period of time, so it takes longer to release
the energy than it does to build it. (Tsunami: Minutes to hours, Floods: hours to days)
5. Get the disaster info you need from reliable sources.
6. Compare tectonic, rock, hydrologic, & biogeochemical cycles
The tectonic cycle is driven by forces deep within the earth’s crust, it involves the creation,
movement, and destruction of tectonic plates, and one cycle can last more than 200 million
years. The rock cycle is the worldwide recycling of three major groups of rocks, driven by the
earths;s internal heat and by energy of the sun. The rock cycle is linked to the other cycles
because it depends oon the tectonic cycle for heat and energy, the biogeochemical cycle for
materals and the hydrologic cycle for water, water plays a central role in weathering, erosion,
transportation, deposition and litification of sediment. The hydrologic cycle is the cycling of
water from the ocean and the atmosphere, to continents and islands and back again to oceans,
it is driven by solar energy and operates by the way of evaporation precipitation, surface runoff
and subsurface flow, Residence time = the amount of time that a drop of water spends in any
one compartment. Biogeochemical cycle is the transfer or cycling of an element through the
atmosphere, lithosphere, hydrosphere and biosphere. The tectonic cycle provides water and
gases from volcanic activity, as well as heat and energy, all of which are required to transfer
dissolved solids in gasses. The rock and hydrologic cycles transfer and store chemical elements
in water, soil and rock. 7. List the 1st and 2nd most common elements in the earth, ocean, and atmosphere.
Earth Core: Iron then Oxygen then Nickel
Earth Crust: Oxygen, Silicon, Aluminum
Ocean: Oxygen, Hydrogen, chlorine
Atmos: Nitrogen, Oxygen, Argon.
8. Describe how viscosity and compressibility relate to the phase of matter.
Viscosity is a measure of how much fluids resist flowing or changing in their shape, the greater
the viscoti the more it resists to change and so the more force is required to make it change.
Viscosity depends on temperature and chemical structure. (Magma = high visc, Water =
Medium, Air = low)
Compressibility: is the amount it is able to be expanded ot squeezed so that miss fills more or
less space. It results in a change of density of the object because of the volume change.
Solids: Not very Fluid/ Not very Compressible
Liquids: Very Fluid/ Not very compressible
Gases: Very Fluid / Very compressible
9. Be able to diagnos