I think I've found out how to make this texture. Maybe not exactly like it, but pretty close.
1. Run clouds on any settings. (you can mess with this to get different results)
2. Duplicate the layer.
3. Uncheck the top layer so that it's "invisible."
4. Median blur the bottom layer. Use a low percentile, 0-10. The radius is up to you. (you can play with these settings, too)
5. Emboss the bottom layer. If the line thing is pointed up, then the rock will be "stacked" down, with things like craters. If you point it downward, then you'll get results closer to the above.
6. Sepia the bottom layer. It should look pretty close to the above picture.
7. Re-check the top layer. It should just be clouds.
8. Median blur the top layer at the same settings you used on the bottom layer.
9. Set the blend mode of the top layer to overlay.
10. Turn down the opacity of the top layer to your liking.
I think this method works pretty well. I haven't found anything else that came as close. Does anyone else have any ideas about how this might work better?