The Science of Disasters Assignment 1

The Science of Disasters

Assignment 1

17 June 2016

1. Distinguish between the theories of continental drift and plate tectonics. What lines of evidence are used to support each theory?

The continental drift is the name of the theory of the earth from around 1925 by Alfred Wegener who suggested it based on the fit of the continental coasts of the Atlantic Ocean, later based on evidence of fossil correlations between southern Africa and South America, but not adopted overall as a theory of geology.

Plate tectonics is the modern term used around the 1960's after geophysicists learned the mechanism of the sea-floor spreading at mid-ocean ridges and earthquakes in the ocean trenches. They were able to learn the facts about the division of the globe into lithospheric plates created and destroyed by the connecting asthenosphere, and were able to adapt this model as a framework within which geologic processes operate.

2. (a) What factors must be considered in estimating the damage from a seismic event? (b) Explain the relationship between the frequency of an event and the magnitude of the event.

Lots of factors must be considered when estimating the damages from a seismic activity. These include: first response, fatalities, business & building loss, suicide, altruism and economic loss. Which will exhaust insurance and moves to tax dollars, this can shock an economy.

“Losses due to earthquakes include not only the cost of repairing or replacing damaged buildings and infrastructure, but also costs associated with damaged contents, damaged inventory, removing debris, renting alternative space, moving to new locations and lost revenues resulting from business interruption. In addition, there are social losses that cannot be directly measured in terms of dollars, but instead can be quantified in terms of injuries, deaths, and the need for emergency shelter. The estimation of losses involves two steps: first the estimation of the level of damage for each type...