How each field is made, I would say no. But a general explanation given can be retrieved from the blog itself, check links below. Below there’s the whole Morphogenetic fields explained through the official blog which are used in Sapien’s videos.
From the official blog
https://enlightenedstates.com/2017/02/22/morphic-fields-create/
https://enlightenedstates.com/2016/06/20/fieldwork/
As for the “why” frequencies do what they do, most have been studied throughout the years. There are some listed, as being testeed and reported for their effects, you can check a compilation done by fellow @MUSICMUSICMUSIC here:
https://forum.enlightenedstates.com/t/full-brainwave-frequency-listing/4005