Hi @mkaragian,
Thanks for reaching out, and welcome to the Speciforum!
When creating a new discipline that does not neatly fit within one of our defaults, we recommend choosing whichever is going to provide you the closest defaults to what you are looking to accomplish. For example, historically we encouraged earth science collections to choose a ‘Paleontology’ discipline, as those featured default forms and field captions most similar to geosciences. For the most part, the type of discipline you choose sets the defaults, but you can effectively mold any discipline to meet your needs. The paleontology disciplines are a bit different, as they also unlock Paleo Context / Geologic Context, additional trees like Chronostratigraphy, Lithostratigraphy, and Tectonic Unit, and new search features for finding objects from within a particular age/time period.
I recommend waiting for the upcoming release of Specify 7.12, expected to launch next week, as we are introducing ‘GeoSpecify’ which will provide reasonable defaults for collections that are comprised of multiple collections (like rocks, minerals, and extraterrestrial materials):