earths structure Flashcards
depth of crust
avg 35 km
depth of upper mantle
700km
depth of lower mantle
2900km
depth of outer core
5100km
depth of inner core
6371km
components of crust
oceanic crust and continental crust
oceanic crust depth
avg 7 km
oceanic crust comp
basalt, dolorite, gabbro
contentental crust depth
avg 35 km
continental crust compostion
granodiorite
mantle composition
fe-mg silicates (olivine, pyroxene, garnet) - peridotite (more compact crystal structures)
outer core composition
Fe with 10% NI S Si
inner core composition
Fe with 10 Ni
discontinuity between lower mantle and outer core
guttenberg (2900km)
discontinuity between outer and inner core
lehmann (5100km)
disconituity just above upper mantle within the crust, marking boundary between lithosphere (above) and astheosphere (below)
moho
crust state
solid
upper mantle state
solid (less dense than lower mantle)
lower mantle state
solid
outer core state
liquid
inner core state
solid
what is the LITHOSPHERE?
near surface, solid cannot flow, carried by astheposphere. Brittle, and has broken into plates. The outermost skin is the oceaninc/continental crust, divided from the mantle lithosphere by the moho.
CRUST + PART OF UPPER MANTLE
what is the ASTHENOSPHERE
in upper mantle composed of perdiotite, is a rhied so can flow. high temp >1300°C (enough for 5% of crystals in periditotie to part melt, creating a film of melted minerals to surround each crystal allowing mantle material to flow more easily). Upper part of upper mantle show plastic properties although still solid. Has lost velocity and causes P and S waves to slow down.
1-5% partial melting
what is a RHIED
a solid material that flows
