What role does gravity play in the layering of planets?
Solid Iron (the heaviest) makes up the core. The outer core is made of liquid iron. The Lower mantle is a solid rocky mantle. Upper mantle is lighter and rocky. Gravity causes respective layering.
What are the 2 major reasons for the increase in density with depth within Earth's mantle?
1) Compression resulting from increased pressure 2) Mineral phase change
Why is seismology responsible for gas prices being more affordable than they might be w/o seismology?
b/c without it a huge number of wells would have to be randomly drilled to find oil. seismology helps find structures where petroleum may be trapped
3 ways that oceanic crust and continental crust differ. Where is the thickest crust found? The thinnest crust?
1. Oceanic crust is created at mid-ocean ridges, continental varies 2. Oceanic crust has similar composition and thickness throughout while in continental it varies. 3. Oceanic crust averages 7 km thick while cont is 40-70
What is the importance of determining the cross-over distance?
It is important to find the thickness of crust for any location. refracted waves enter mantle, seismographs near the center record waves first then seis mos further from center record waves 2nd. pt at which both waves arrive at same time is cross-over
How do S waves tell us the mantle is solid?
B/c they go through it but then are blocked my liquid outer core