In the manga, alchemy is said to have been taught to Amestrians over 350 years prior to the start of the series by a mysterious man known as The Philosopher from the East and is explained to harness the diastrophic energy that is released from the movement and collision of tectonic plates deep within the Earth's crust to power transmutation.
I am simply confused between the correlation of tectonic plates and alchemy's power. How does the tectonic plates moving act as the fuel for any non-p.stone transmutations??? Alkahestry's source of power being "chi", or the lifeforce of the earth itself makes perfect sense; so why is alchemy powered by the movement of tectonic plates? That's so random to me.