Science Unit 5 Flashcards
what is a rock
A material made of multiple minerals
What’s a mineral
A material made of multiple elements
Erratic
a rock different from the others around it that is a product of the glaciers
Continental Drift
Plants and animal remains can be found in different areas then their supposed to be, the continents look like they can fit together,rocks are in different areas,geological evidence like glaciers leave rocks and coal deposits can be found in unusual places
how are subduction zones, mountains and volcanoes made
a oceanic plate and a continental plate collide
how are mid ocean ridges formed
two ocean plates move apart
how are mountains made
two continental plates collide
what makes plates move
convection currents in the mantle
sea floor spreading evidence
rock is younger closer to the mid atlantic ridge Old rocks are farther,the sea floor is always getting bigger
how are earthquakes measured
with a seismometer on a seismograph
p waves
fastest waves, can pass solids liquids and gases,not very dangerous
s waves
travel half the speed of p waves, pass solids,do more damage than a p wave
surface waves
slowest waves, travel on the surface,cause the surface to roll and do the most damage
ring of fire
a ring of volcanoes around the pacific that mostly occur at subduction zones
fold mountains
formed when rock layers get compressed horizontally by great pressure
block mountains
two rock slabs collide and one ends up on the other and pushes it up
petrified fossils
organisms original parts are disovled by water and replaced by silica (quartz)
Carbonaceous films
temp and pressure leave a thin bit of residue on the fossil so only a outline is left
original remains
the whole organism is trapped and kept in ice,amber or tar
trace fossil
impression of a fossil left in hardened mud eg. footprint
molds
the hollow space left in sediments when a organism dies and decomposes
superposition
a principle that says in untouched rock layers (strata) the oldest rock is at the bottom
relative dating
a technique used to find the order events in history happened
slow pressure on a rock can cause it to
fold or break
