[dgt20 (OP)]

how did scientists create and develop these plate tectonic force theories? what evidence did they actually gather to lead each force? from what i know these theories have been constantly developed by other scientists, is this also true?
ridge push
slab pull
mantle convection
trench suction

[alancalverd]

Don't know about anyone else, but when I was about 10 yeas old I looked at a map and thought "if the Atlantic Ocean wasn't there, all the land bits would fit together."

I guess other people had the same idea around the same time (1950s).

[guest45734]

Alfred Wegener appears to the originator of the idea.
"In 1912 the meteorologist Alfred Wegener amply described what he called continental drift, expanded in his 1915 book The Origin of Continents and Oceans[32] and the scientific debate started that would end up fifty years later in the theory of plate tectonics" https://en.wikipedia.org/wiki/Plate_tectonics#Development_of_the_theory

[gem]

Hi all
although not the first Wegener is still head and shoulders the main point of reference when considering continental drift/plate tectonics.
There is still active discussion around the mechanism driving the phenomena, but science has had to accept the general principle, once the weight of evidence became to compelling ie mid Atlantic ridge and the generation of new crust.
see link
https://earthobservatory.nasa.gov/features/Wegener/wegener_6.php

Quote ;
"Beginning in the mid-1950s, a series of confirming discoveries in paleomagnetism and oceanography finally convinced most scientists that continents do indeed move. Moreover, as Wegener had predicted, the movement is part of a grandscale process that causes mountain-building, earthquakes, volcanic eruptions, sea-level fluctuations, and apparent polar wandering as it rearranges Earth's geography."

In regards to the forces required Wegener stated;

"The Newton of drift theory has not yet appeared."