There was lava in the area near the wells that the Puna Geothermal Venture facility created.

The plant has nine wells that run as deep as 8,000 feet, according to Wil Okabe, managing director for the County of Hawaii. -Washington Post

8,000 feet is really quite deep. While I understand that those are not the deepest wells created for geothermal energy, in Hawaii that seems deep enough to get to where lava would also be pooling.

For example, it would be deep enough to hit the pool at one of the main volcanoes.

Rocks that are moving upward in the mantle beneath Hawai`i begin to melt about 40 to 60 miles (60 to 100 km) depth. The molten rock, called magma , rises because of its relatively low density. The magma "ponds" in a reservoir 1 to 4 miles (2 to 6 km) beneath the summit. https://www.nps.gov/havo/faqs.htm

In addition to the availability of lava in the area near the wells, it seems that geothermal energy has also been linked to earthquake activity in the past.

An analysis of earthquakes in the area around the Salton Sea Geothermal Field in southern California has found a strong correlation between seismic activity and operations for production of geothermal power -UC Santa Cruz

Moreover, the facility itself is basically right on the location that the set of fissures opened up.

Puna GeoThermal Venture Map

As location of seismic activity is in question here, I also found a map from the US Geological Survey with 30 days of activity for this portion of Hawaii.

enter image description here
The largest circles are a 5.4 and 6.9, the smallest ones are equal to or greater than 2.5.

Given the proximity of the facility, as well as the fact that these wells were not only near underground lava, but also have been known in other areas to produce earthquakes, what roll, if any, could the Puna GeoThermal Venture have played in the recent fissure activity in Pahoa, Hawaii?

  • 2
    $\begingroup$ I think any answer would be speculative. What mechanism from the plant operation would affect the volcanic activity? I don't think the amount of heat or fluid removed would have any impact on the magma. It is true that fluid reinjection, as used at the plant, has been linked to increased seismic activity. It seems hard to believe that that would be significant compared to the pressures from the moving magma, and I would expect that it wouldn't have cause the initial fissures to open further to the southwest. It might be worth a study or at least some back of the envelope calculations. $\endgroup$ – haresfur May 24 '18 at 2:26
  • $\begingroup$ @haresfur - With regards to the comparison of the location of the power plant versus magma, I added a map of the past 30 days of seismic activity to hopefully add more information. I think it may be speculative to state there was causation without evidence, however, I would hope that an answer would at least articulate contributing factors in this scenario so as to at least get a better picture of what may or may not have played a factor. $\endgroup$ – Travis J May 24 '18 at 4:53
  • 2
    $\begingroup$ My feeling is that "no" because the fissure (a surface representation of a dike) is orders of magnitude larger in scale and energy than that geothermal facility. $\endgroup$ – Gimelist May 24 '18 at 5:18
  • 1
    $\begingroup$ I'd be very careful here about correlation / causation. The geothermal wells would naturally be drilled in a hot area. $\endgroup$ – Semidiurnal Simon May 24 '18 at 8:51
  • 3
    $\begingroup$ I would posit that the fissures' proximity to an active volcano has far more to do with the recent activity than a tiny (on a geologic scale) energy plant. I can state with some certainty that there has been volcanic activity in that area well before that plant was installed. $\endgroup$ – Tim Nevins May 24 '18 at 13:52

I think we can confidently enough answer "no".

From this report (p. 23):

Kilauea eruptions occur either at its summit or within two well-defined swaths (called rift zones) that radiate from the summit.

In the same report, you can see those rift zones on the map page 3, or on the sketch of the plumbing system page 24. Most lava flows are emplaced along these rift zones. For instance, look at this map of the 1955 eruption (public, USGS):

Vents and lava flows from the Kilauea eruption of 1955

You can see that the flows were emplaced in a zone very similar to the 2018 eruption. Apparently the power plant opened in 1993, and the first exploratory wells were drilled in 1961-62, so after this event.

Actually, the rift zones are in the lava flow hazard zone 1, i.e. the most severe. The zone is defined as follow by Mullineaux et al. (1987):

Zone 1 consists of the summit areas and active parts of the rift zones of Kilauea and Mauna Loa; in those areas, 25 percent or more of the land surface has been covered by lava within historical time, during the 19th and 20th centuries. These areas contain the sites of most historical eruptions, and a large majority of the lava flows that will affect other zones on Kilauea and Mauna Loa in the near future probably will originate in zone 1. [emphasis added]

So the real question is: why was the plant (and estates...) built in an area well known for lava flow hazards?!

To conclude, by researching the plant I found that it is actually where people accidentality drilled through a magma pocket for the first time (Teplow et al. 2009)! They hit a pocket of dacite; it did not trigger an eruption. This happened later in Iceland: this time, they even used it as an experimental well (there is a whole issue of Geothermics on this). Again, no eruption.

  • 1
    $\begingroup$ Thanks for taking the time to write this up, the citations are very reputable. Highlighting the issue of the rift zones, the historical activity, similar circumstance, and the classifications from the USGS are all strong indicators that the plant did not contribute to the flow. $\endgroup$ – Travis J Jan 8 '20 at 21:52

Reinjection of cooling effluent over decades has got to break down the rock, in fact it probably explodes the rock into tiny pieces which after decades crumbles and lets the lava move...

All of the scholarly industry information available says not to place geothermal plants in seismically active areas...


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.