ANSWERS SURE A+
✔✔evidence for plate tectonics theory - ✔✔-spatial relationship of current continents
-paleontology-related fossils on continents separated by ocean-shows they were once
joined
-mountain ranges- stratification/layering of mountain range match that are found on
different continents indicating continents were once joined
-magnetic reversal of rocks-seen at mid-ocean ridges
1. at mid-ocean ridge, which is a divergent boundary magma is cooling forming new
crust
2. molten lava has no magnetism but as cooling acquires magnetic orientation of the
earth's polarity at the time
3. rocks show magnetic orientation is symmetrical to both side of ridge
4. rocks further from the ridge are older than rocks closer to the ridge
-seafloor spreading- measuring moving divergent plates at mid-ocean ridges
-sonar- mapping of the seafloor
✔✔hydrothermal vent formation - ✔✔1. cracks in ocean floor where cold water seeps in
2. water is superheated by the underlying hot magma
3. hot water builds up pressure, causing it to rise hot magma
4. dissolves minerals on the way out
5. some minerals precipitate out along edge of crack forming a vent
, ✔✔isostasy - ✔✔buoyant properties of layers of rocks which float on other layers,
according to their density and thickness. this explains why the earth's crust floats on the
denser, underlying layer, just as an ice cube floats in a glass of water. the principle of
isostasy shows that the earth's crust is generally higher where it is thicker and less
dense; lower where it is thinner and denser. continental crust is less dense as
compared to oceanic crust
✔✔describing features and how they are formed - ✔✔-state the definition of the feature
-state the type of boundary that forms feature
-describe how boundary forms feature
✔✔littoral zone - ✔✔a. define the term littoral zone
-area between high and low water marks/area submerges at high tide and exposed at
low tide
✔✔shape of a shore - ✔✔-two processes that effect the shape of any shore are
sedimentation/deposition and erosion.
a. define erosion as-the removing/moving/carrying of sediments
-this forms rocky shores
-caused by high energy or fast/strong water/wave action, currents
b. then, define deposition/sedimentation as- the depositing/accumulating of sediments
to the shore
-sedimentation forms muddy shores
-caused by low wave energy-allows particles to drop out of solution/to settle
✔✔outline the environmental factors affecting organisms living at shores - ✔✔-need to
be able to resist wave action
- rocky shore- cling to rocks/live under shelter/holdfast/attach/tough shells
-sandy shores- burrow, gave tough shells
-tides exposed to air-need adaptations to survive drying out/desiccation
-change in temperature- must be able to adapt such as burrowing/look for shelter
-changes in salinity- tide pools evaporate = salinity increases; rains in tide pools =
salinity decreases
-exposed to predators for part of the day- need to hide/camouflage
✔✔explain how different patterns of erosion and sedimentation give rise (forms) rocky
shores and muddy shores - ✔✔-erosion is the removal of rock
-sedimentation is the dropping of rock
-rocky shores develops where erosion is greater/high than deposition
-erosion is caused by fast/strong water movements
-where rocks are resistant to weathering
-muddy shores develops where sedimentation is greater/higher than erosion
sedimentation is caused by slowing down of wave movement