This would be cause and effect since the passage talked about the event and what happened due to it.
"Located in Death Valley, California, the rocks are sitting on the red hot ground". "Unlike normal rocks they have trails etched out behind them".
This means that as a result of The Drifting Rocks phenomenon, the rocks have trails etched. I do believe that it could be fact by fact but in the 2nd paragraph it doesn't provide concrete evidence. However, it does list the facts in the first paragraph and what the rocks looked like when the phenomenon occurred.
