Module One Flashcards
Define Oceanic Crust
portion of the earth that is relatively dense, contains basalt and is about 5 kilometers thick
Define Continental Crust
portion of the earth that is less dense, contains granite and is 20 to 50 kilometers thick
Define Mid-ocean ridge (trench)
continuous chain of underwater volcanic mountains encompassing the earth
Define sediment
loose mud or sand that settles to the bottom of the ocean floor and gets thicker as you move away from the ridges
what are magnetic anomalies?
when the magnetic particles are pointing south instead of north
Plate tectonics ?
movement of the earth’s plates
what’s seafloor spreading?
the creation of new seafloor due to the plates moving away from each other at the mid-ocean ridges
what is subduction?
downward movement of a plate when another plate slides over it
what’s a fault?
when 2 plates slide past one another causing an earthquake
continental shelf
gently sloped shallow sect at the edge of a continent extending to the shore point to where the slope gets steeper
continental slope
steeper sect of a continental edge extending seaward
continental rise
gently sloping area
