#LFHZ

The long-term likelihood of an area being invaded by lava in the future, is estimated in two different ways based on the history of lava flow activity. One approach uses a geologic map to calculate how much land surface was covered by lava during different periods going back into the past; the resulting numbers are called coverage rates. Another approach calculates how frequently lava flows have occurred within specific areas over time; the resulting number is a lava flow probability.