What is a method by which the present rate of motion between two ...

[tatyanajohnson]

What is a method by which the present rate of motion between two plates can be measured accurately? What will be an ideal response?

Question 2

How are hot spots used for determining the absolute motions of plates? What will be an ideal response?

[aadams68]

Answer to Question 1

The travel of a laser beam can be timed from one plate to another by bouncing it from a satellite and
by calculating the difference in arrival times of a quasar signal at two plates over a period of time.

Answer to Question 2

Hot spots appear to be fixed in the mantle relative to each other, so they can be used as a reference
frame. If the age of a basalt and its distance from the hot spot is determined, then the rate of movement
of that rock can be calculated. If a number of these samples are taken from various distances from the
hot spot, the calculation can be quite accurate.

[tatyanajohnson]

TYSM

[xiazhe]

Thanks for the timely response, appreciate it