sinkholes schema

Greetings

I am working on two versions of an online map of sinkholes autogenerated by
RSS feeds from news alerts

The most advanced version of the system would extract certain data from the
feed (location, size, depth, cause etc), It came to mind that it would be
useful to  have a sinkhole data schema  to start with

Checked the schema.org and found 'emergency' which could (or could not) be
a top level category for sinkholes

However, noted that emergency in schema.org is classified as a medical
event. That would not do

So, I wonder if others see the need to bump up 'emergency' to be a broad
term for various types of emergency (medical being one of them)  and if
this makes sense in this project, and how to do that?
https://schema.org/Emergency

alternatively, I could propose a different type of top level term
such as 'geological occurrance' and stick the sinkhole uner that, but would
that make sense?


secondly, have not yet found out how to create a new schema
(browsed the documentation but there is no entry on
how to start a new schema). have I just not seen it?
https://schema.org/docs/faq.html


pointers welcome
thankz

PDM