Week 3: Rocks

Question 1

3 types of rocks

Answer 1

1. igneous
2. metamorphic
3. sedimentary

Question 2

how are rocks distinguished

Answer 2

through minerology and texture

Question 3

igneous rocks

Answer 3

• formed from magma that originated in deep earth and moved up toward the surface
• magma either erupts on the surface creating a volcanic eruption (extrusion) or stalls below the surface (intrusion)
• minerals are eroded and carried down rivers and deposited in layers as sediment
  this occurs in low gradient rivers, valleys, lake and oceans

Question 4

sediment

Answer 4

1. rocks (and minerals)
2. living things (shells, wood, bones)

Question 5

lithification

Answer 5

process of compacting and cementing

Question 6

sedimentary rocks

Answer 6

sediments pile up, the earlier sediments are buried deeper, and are subject to high overburden pressure, becoming more compacted. Various chemical changes take place cementing the particles together forming a sedimentary rock.

Question 7

metamorphic rocks

Answer 7

sedimentary and/or igneious rocks that are buried deeper and undergo chemical change and higher pressure

Question 8

metamorphism

Answer 8

chemical change, higher temperature and greater pressure changes an ingnious/sedimentary rock into a metamorphic rock

Question 9

look at rock cycle

Answer 9

slide 14 week 2

Question 10

what type of rocks preserve dino fossil

Answer 10

sedimentary- perfect temperature and amount of pressure for fossilization.
Igneous- too hot for bones to survive, fossil will only work if its ash that covers the bones.
Metamorphic- too much pressure will break the bone.

Question 11

What happens after death: quick burial

Answer 11

dino dies
replacement and/or permineralization
nearly complete specimen exposed (dug up)

Question 12

What happens after death: dismemberment before burial

Answer 12

dino dies
dismemberment before burial, scavenging and other natural processes
isolated bones buried and mineralized
isolated bones exposed (dug up)

Question 13

types of sedimentary rock

Answer 13

low energy= clay/shale/mudstone
medium energy(medium movement of rocks/pebbles)= sand stone
high energy(high movement, larger rocks and not smooth looking)= conglomerate

low energy better for preserving bones as high energy would break them done

Question 14

what terrestrial environments preserve fossils

Answer 14

on land
quiet water- low energy to preserve bones
rapid burial- mud slide/shore of lake
low energy

Question 15

Layers of the earth (3)

Answer 15

1. crust- layer closest to the surface
2. mantle- second layer
3. core- center layer (inner and outer core)

Question 16

lithosphere

Answer 16

rigid crust and upper mantle
brittle rock, if force is put on it it will snap not bend

broken into number of large plates (tectonic plates) and many more smaller plates that move on the ductile athenosphere

Question 17

asthenosphere

Answer 17

partially molten or deforms fluidly like plastic under pressure, becomes ‘bendy’

Question 18

3 type of boundaries where plates interact

Answer 18

1. convergent- come together, one plate moves on top of the other
2. Divergent- plates move apart from eachother, a new crust is formed
3. transform- plates move side to side

Question 19

subduction

Answer 19

when one plate goes under the other, pressure will build, rock will get stuck and then earth quake happens

Question 20

what where the plates like during the Mesozoic era?

Answer 20

early triassic- all continents were together, called pangea. Sea level is low.

late jurassic- slowly splitting apart

late cretaceous- all continents are split. Sea level is high