Soft Question: How Best to Thoroughly Exhaust the Literature
I would suggest combing Google Scholar with the following methods:


Search keywords just as you've mentioned.   
When you hit on a semi-relevant paper, check the citations for relevant information.
Additionally check the collected works of the authors of said papers.  
Search specifically for review papers or graduate-level textbooks for context on a subject and more citations.  


The perk of interdisciplinary Earth Science is that everything connects.  The downside of interdisciplinary Earth Science is that information is dispersed.  Good luck.