Its a partial aircraft
There are no shadows beneath the "wings."
It has no landing gear
The leading edge of the root of the "vertical stabilizer" is ahead of the "wingtips" and starts (from "nose" to "tail") at the aft, trailing root of the "wings" --- there is no such aircraft shape in the inventories.
It is a partial aircraft
To the "southeast" of the "jet," there is a collection of similarly-colored material, probably a pile of rocks associated with the "structure."
????
????
Yeah, I scratched my head 'til it bled after reading that one, too.
I wonder if the Marines who found the "jet" at this location today can tell the difference between an aircraft and a pile of rocks...