Here are some resources for looking up definitions for terms that may come up in the resources that you find:
The following reference works are only a small representation of the reference collection in the disciplines of Earth Sciences and life sciences. The library's reference collection is extensive and will contain many similar dictionaries and encyclopedias for hundreds of subject areas. An easy way to find additional reference works would be to do a SUBJECT search in the library catalog. For example, to find dictionaries and encyclopedias in Sedimentology you would perform a subject search on GEOLOGY and ENCYCLOPEDIAS
When in doubt as to the proper subject heading try a TITLE search on your topic.