Wonderful captures. Death Valley holds more wonders to photograph than perhaps any other place on earth. It's an unforgiving environment for the unprepared, and the shift in temperatures can vary as much as 80 degrees F in a 24 hour period. I've been out there when the temp dropped so fast, you could actually hear the rocks break, almost shreiking in the night air. Lots of flora and fauna, incredible rock formations as you've so generously shown us and as much sand as any box could handle.
You are quite the traveler!