Investigators in the United States have ‘blown the lid off’ the Yellowstone supervolcano’s inexplicable underground reservoir of magma. A gropu of geologists and Earth scientists at this time claims to have finally found the deep magma ‘cap’ that maintains the volcanic system’s high pressures and temperatures locked up underground. Scientists liken the result to steady breathing, as if the volcano was in a calm slumber. However, if enough air was restricted in the supervolcano’s ‘throat’, then at some point an eruptive snore might bellow forth. Thankfully, the magma cap output sort of like a CPAP machine, keeping internal pressures relatively stable, permitting the supervolcano to sleep somewhat soundly.
Get to know the northeastern part of the Yellowstone caldera
The lid to this volatile Pandora’s box exists between 3.5 and 4 km (2.2 and 2.5 miles) under the northeastern part of the Yellowstone caldera, according to new studies and it seems to be usually letting out little belches of gas, keeping an explosion at bay.
Earth scientist Brandon Schmandt from Rice University explains that for decades, we’ve known there’s magma beneath Yellowstone, however the exact depth and structure of its upper boundary has been a huge question. In additio, what they’ve found is that this reservoir hasn’t shut down, it’s been sitting there for a couple million years, but it’s still dynamic.
Nowadays, abundant proves submit that there is a magma reservoir sitting in Earth’s crust, just beneath the northeastern part of the Yellowstone caldera. How deep that reservoir lies and how much magma it holds, nevertheless, are still up for debate these days. Schmandt’s co-lead author Chenglong Duan developed a new method to image Earth’s crust in the Yellowstone region. The methods relies on sending seismic waves, akin to tiny earthquakes, into the ground from a vibrating truck to see how they travel through rock layers.
The algorith that reads through noise data
As these waves reflect back to the surface, they are complied by hundreds of seismometers. Collaborating with geophysicist Jamie Farrell from the University of Utah, the group developed an algorithm that reads through all this noisy data to elaborate a model of layers in Earth’s crust. It has at this time provided what Duan says are the “first super clear images of the top of the magma reservoir beneath Yellowstone caldera.”
About 3.8 kilometers below the surface, the probing seismic waves encountered a sudden boundary. They no longer appeared as though they were flowing through rock. Alternatively, their sluggish movements proposed that they were moving through a muddy mixture of supercritical fluid and magma between 3 and 8 kilometers deep. The scientists have interpreted this boundary as the “sharply defined top of the magma reservoir.”
What only stops such an eruption: gradual cooling and crystallization
The only subject stopping such an eruption is the gradual cooling and crystallization of sludgy material in the upper crust, which creates this minimally leaky magma cap. The team concluded that due to the estimated total porosity at the top of the reservoir (approximately 14 percent) is well below typical eruptive porosities, our results align with previous assessments that this caldera-forming volcanic system is in a state of repose.
