How do you define supernatural thriller versus horror? It's a tricky grey area, I find. My readers sometimes ask how scary my books are. They range from properly scary (Spectre of Springwell Forest, The Irresistible Summons) at one end of the horror-thriller spectrum, to suspenseful rather than scary at the "thriller" end of the spectrum (Phantom Audition, The Birds Began to Sing). But I'd say all of these novels could be called "supernatural thrillers" as well, mainly due to the major mystery elements.

I'll have to check out some of your fiction. :)