phreatic

American  

[free-at-ik] / friˈæt ɪk /

adjective

Geology.

1. noting or pertaining to groundwater.

2. noting or pertaining to explosive volcanic activity involving steam derived from groundwater.

   a phreatic explosion.

---

phreatic British  

/ frɪˈætɪk /

adjective

1. geography of or relating to ground water occurring below the water table Compare vadose

---

Etymology

Origin of phreatic

First recorded in 1890–95; from Greek phreat- (stem of phréar ) “artificial well” + -ic

Example Sentences

Outside the permanent danger zone, the volcanology institute warned people including those living on the vulnerable southeastern side of the volcano to stay alert “due to the increased possibilities of sudden and hazardous phreatic eruptions.”

From Seattle Times • Jun. 4, 2022

Dominica last suffered major phreatic or steam-drive volcanic eruptions in 1997, and before that in 1880.

From Reuters • Sep. 18, 2020

"It's possible that there's no magma involved, that it's just a phreatic eruption - a steam eruption. We don't know yet."

From BBC • Dec. 9, 2019

But they are geological phenomena: sometimes, the only warning we get before something catastrophic happens is the general seismic and phreatic precursor activity, which sometimes fades away with only a murmur.

From Scientific American • Aug. 9, 2012

Throughout the day, phreatic eruptions followed a pattern: steam and ash to begin, steam only as their finale.

From Scientific American • Jul. 7, 2012