chapter 25.3 and 25.4 Flashcards
what is the boundary that marks a density change between layers?
discontinuity
how can discontinuities be identified
studying seismic waves
what are shadow zones?
areas where no seismic waves are recorded
what is another name for shadow zones?
dead zone
between what degrees do shadow zones fall?
between 105 to 140
is the outer core solid or liquid?
liquid
is the inner core solid or liquid? why?
solid because there is so much pressure
what makes up the lithosphere?
the crust and upper most mantle
what is the asthenosphere?
a plastic like layer which earths plates move
what elements make up the mantle?
calcium,aluminum,iron and magnesium
what elements make up the core
iron and nickle
the measure of a fluids resistance to flow
viscosity
chemical compound silicon dioxide
silica
tend to be small have heights in hundreds of meters of range
cinder cone volcanoes
are broad flat structures composed of layer upon layer
shield volcanoes
are large and steep-sided often thousands of meters high and tens of kilometres
composite volcanoes
what is molten or liquid rock stored inside earth
magma
where is the ring of fire located
pacific ocean
what are two specific locations where volcanic activity occurs do to divergents
east african rift valley
are hotspots stationary
yes they are
if magma has a high viscosity will it contain more or less silica
more
what is pyro-clastic material
what is the smallest type pryo clastic material
volcanic ash
what is the largest pyroclastic material
volcanic blocks and bombs
