Science Fiction or Action-Adventure: Which??

Science Fiction or Action-Adventure?
When "Season of the Plant", my first book, was published last year I chose to brand it "science-fiction" because the plot dealt with paleontology and archeology. These I know are not the classic themes of sci-fi, and yet accurate science is key to the story, which moved to pure fiction with the paleontological horror that is the central idea. I now wonder. Since action-adventure-thriller is the way the story moves, and sci-fi traditionally deals with the future, I am thinking to change my presentation of the work. The book is part of a series of action-thriller stories based on scientific expeditions to different parts of the world (the second in Norway, the third in the Hawaiian Islands). Where does science fiction end as a proper designation of a book, when it is fiction and science is a core element in the story?
My second book, to be published in the near future, "That Which Endures", is definitely sci-fi, taking place a century and a half in the future, and dealing with classic sci-fi themes, including a central incident of time-travel (though the book does not hinge on it). It is still an action-adventure-thriller, but since it takes place in the future, I imagine the sci-fi genre is where it belongs.
None of my work is fantasy, which clearly has a home in the sci-fi genre. Since genre is vital to promoting a book, I find myself in a real quandary as to where to go with the problem. Where do my books fit?