WTG - Ch 6. Water, Water, Everywhere Flashcards
(2 cards)
Describe the Zanclean Flood.
5.3 million years ago about 250,000 years before the shallow narrow straights of Gibraltar between Europe and North Africa were closed due to tectonic action which cut the Mediterranean Sea off from a supply of water from the other oceans and then the areas hot climate caused enough evaporation to dry up most of the sea creating a basin 2.5km below sea level. Which subsequently became a desert wasteland until sea level begin to rise again and erosive forces wore away at the rock enclosing the Mediterranean. the Zanclean flood broke through the straights of Gibraltar cutting a 250m channel and rapidly refilling the basin 10cm a day.
What affect will sea level rise have on the earthquake hazard here on the west coast of BC?
The earthquake hazard is related to an oceanic vs. continental convergent plate margin. The largest earthquakes occur at the coast or further offshore. As sea level rises more weight will be added to the crust. This may affect the stress that continues to build up at this plate margin. As stress changes more, larger earthquakes may occur. It may also be that fewer earthquake may happen. It may also be that earthquake activity changes location.
