Chapter 7 Flashcards
the plate tectonics theory states that:
the Earth’s outer layer is made up of plates which have moved throughout Earth’s history
who first formed the continental drift theory
Alfred Wegener
the continental drift theory states that:
approximately 225 million years ago the continents were all one big supercontinent called Pangaea
continents developed when
plate movement occurred
a Mid Ocean Ridge (MOR) is:
a system of mountain ranges on the sea floor that are separated by valleys
Mid ocean ridges were discovered by
SONAR
mid-ocean ridges form through a process called
seafloor spreading
the three main types of plate boundaries are
convergent, Divergent, and transform
a convergent plate boundary is where
two plates collide
subduction, volcanic arcs, earthquakes, and continental collision (high folded mountains) are all the result of
movement at a convergent boundary
Continental Collision is
when plates of equal density Collide and do not subduct at a convergent plate boundary which form High folded mountain ranges where volcanic activity is absent and there is no deep sea Trench
a divergent plate boundary is where
two plates are moving apart
mid-ocean ranges and rift valleys form at
divergent boundaries
a transform plate boundaries where two plates
slide horizontally past each other in opposite directions
stress, fault lines, and earthquakes are caused
by transform boundaries
the four main processes that cause plate motion are
convection, slab pull, Ridge push, and friction
convection currents result from the continuous ________ of the Earth’s crust that causes plates to move
heating and cooling
slab pull occurs when an oceanic plate is pulled farther down along a _______
subduction zone
Ridge push occurs when gravity pulls material ________ from the mid-ocean ridge
downward and away
friction between _________ can also affect the motion of plates if Continental or Oceanic material is being drug Along by plate
a plate and the mantle
physical changes to the Earth’s surface include changes in the _____ of a material
size and shape
chemical changes to the surface of the Earth include changes in the _____ of thematerial
chemical composition
weathering is
the process that involves the physical or chemical breakdown of materials on Earth’s surface
factors that influence weathering include
the agent such as water air, the composition of the material being weathered, the climate, or the time
