To combat regional power grid instability, energy directors plan to construct geothermal plants along an active fault line, where subterranean heat is greatest. Skeptics claim that drilling deep geothermal wells in seismically active areas risks triggering earthquakes that damage local infrastructure. However, the lead engineers contend that operating these geothermal facilities will net a decrease in major seismic hazards. They reason that extracting subterranean thermal energy cools surrounding rock formations, inducing thermal contraction that gradually dissipates accumulated tectonic tension via harmless micro-tremors rather than catastrophic faults. Which of the following, if true, provides the strongest support for the lead engineers' contention?
- Geological monitoring of fault systems subjected to sustained thermal cooling indicates that frequent micro-tremors effectively vent stored strain, preventing the buildup of stress required to initiate major earthquakes.Answer
- BRapid thermal contraction in deep rock formations creates micro-fractures that increase subterranean fluid pressure, substantially destabilizing neighboring fault planes.
- CGeographic regions containing natural geothermal activity report a lower overall incidence of major earthquakes than geothermally inactive regions.
- DMunicipal buildings located near the proposed geothermal sites were recently retrofitted with reinforced foundations designed to withstand moderate tremors.
- EGeothermal power plants produce baseload electricity at significantly lower operational costs than biomass or hydroelectric facilities in mountainous regions.