One place to start, even as a professional, is with a textbook. Reading summaries of ideas on the broad topic region commonly provides abundant material to get you started on the path to a good topic and eventually to a defensible position. Most text book chapters have excellent bibliographies which can also get you started on your search for references. A second source for paper topics is the Discussion and Reply section found in many scientific journals. The most interesting papers are controversial and generate discussion regarding divergent points of view.
People disagree about issues and write papers to state their points of view.
The library records arguments. A reasoned argument is usually very stimulating and is really the foundation of hypothesis testing in science. Another researcher believes the methodology is wrong, the observation is incorrect, or the data has been misinterpreted and replies. In either case, the writer's task is to persuade a reader regarding a scientific point of view. A good place to find argument is in a journal like the Geological Society of America Bulletin or the Annals of the Association of American Geographers which contain a Discussion and Reply section.