25.3 and 25.4 Flashcards
what is the boundary that marks a density change
discontinuity
how can discontinuity be identified
by using seismic waves
what are the shadow zones
where no seismic waves have been recorded
what is another name for a shadow zone
dead zone
what are the degrees that shadow zone fall
between 105 and 140
is the outer core a solid or a liquid
liquid
is the inner core a solid or liquid? why?
solid, due to the preasure
what is a lithosphere
the crust and uppermost mantle
what is the asthenosphere
a weaker plastic-like layer upon which earths lithospheric plates move
what matalic materials make up the core
iron and nickel
what elements make up the mantle
calcium, aluminum, iron, and magnesium
boundary between two layers of material that have different densities
discontinuity
areas on earths surface where no seismic waves are recorded
shadow zone
the crust and uppermost mantle combine
lithosphere
tectonic plates move on top of a plastic-like layer of the upper mantle
asthenosphere
measure of a fluids resistance to flow
viscosity
chemical compound silicon SiO2 which is a common ingredient in most magma
silica
tend to be small, have heights in the hundreds of meter range, and have short eruption cycles
cinder cone volcano
are broad, flat structures composed of layer upon layer of lava flow
shield volcano
large and steep sided often thousands of meters high and tens of kilometers across the base and composed of layers of both lava and ash
composite volcano
what is molten or liquid rocks stored inside Earth?
magma
where is the ring of fire located
in the pacific ocean
what forms do tectonic plates create when they collide?
volcanoes
which two specific locations can volcanic activity occur due to divergent
mid-Atlantic ridge
East African Rift Valley
