Scientists are carefully monitoring a swarm of small earthquakes that erupted on Monday in the Salton Sea below the southern tip of the dangerous San Andreas fault.

They are concerned about the possibility that the swarm could trigger a larger event, a phenomenon that has occurred in that region in the past.

Scientists said Monday afternoon that there’s a less than 1 percent chance that the swarm will produce a 6.0 or larger quake within the next month. But the location of the swarm is worrisome due to its closeness to the San Andreas.