What's startling is that the invented elements have been done so well. (One tolerable, perhaps inevitable, exception is a moist, uplifting coda.) Without giving any plot points away, I can tell you that a climactic scene turns on a marvelous surprise, and promise you frequent spasms of suspense that will grow almost unbearable.
In its simplest state, this is geographical data with a timestamp, but when you plot this data onto the scenery of a map and then create a shifting window into the scene through the sequence of time, you create a data-driven story.