Plate positions relateive to each other

Question 1

What can be calculated to understand plate positions?

Answer 1

The paleo-latitudes and paleo-longitudes of the earth’s magnetic poles at a given geological time can be calculated from the paleo-inclination and the paleo-declination of the magnetic field frozen in a rock sample that was formed at the time, with the sample dated using standard techniques

Question 2

If the magnetic paleo-latitude and paleo-longitude in the rock sample are different to present-day magnetic latitude and longitude, why could this be the case?

Answer 2

The earth’s magnetic field and therefore position of the magnetic poles might have changed over time
The rock must have moved over the surface of the earth

Question 3

What was calculated before plate tectonics was accepted?

Answer 3

Polar wander curves from changes in magnetic inclination and declination but were puzzled to why the curves differed for different continents

Question 4

What explain the curvature of magnetic poles?

Answer 4

The continents might have moved relative to one another
The earth’s magnetic field isn’t actually an axial dipole and has a more complicated form

Question 5

What are curves known as?

Answer 5

So these curves are now called ‘Apparent polar wander (APW) curves’, and every continent has its own APW curve