>>12090344adding to this
if the rocks are about the same age you will see the same patterns in the magnetic barcode shit on both sides of the rift
this only works with ferrimagnetic materials, but the stuff that comes out of mid-ocean ridges has plenty of iron and most sedimentary rocks have a bit of it too so you can just tow a magnetometer along the seafloor and it works fine
basic geology theory is really simple, it's just applying it to the clusterfuck of shit you actually see in the real world where it gets complicated
