I saw that too; it was strictly Army though....Fort Irwin, which is just outside of beautiful downtown Barstow.
The Marine Corps has it's own (and plenty of it!) desert scenario with Twentynine Palms.
Years ago, before urban sprawl began to hit even the low desert out here, we could hear the boom-boom from "The Stumps" late at night, when Twentynine Palms was pretty much just an artillery base....and it's gotta be 30 miles away as the crow flies (probably 100 driving).
I'm glad you saw it too. I heard it from the kitchen and when I went in and watched the rest of it, I thought I had heard Marines and soldiers and I didn't think they trained together. But things have changed so much in the 18 years since my husband retired from the AF, I thought maybe they did. It was interesting, wasn't it? I wish they would do more reporting that shows everybody what great people we have in the military.
Where the hell IS 29 Palms? : )