Elaborate Hawaiian seamount structures built by iron-oxidizing microbes. Loihi Seamount and its "rust villages": Structures built by iron-oxidizing microbes. Her name brings visions of fire, lightning, wind--and volcanoes.
Of the ancient Hawaiian goddesses, Pele, the "lady in the red dress," is the best known. Locals believe that her powers formed Hawaii's chain of volcanic islands. The word pele means molten lava in Hawaiian. Volcanic eruptions, or Pele's tears, it's said, are her way of expressing red-hot emotions. The island volcanoes of Hawaii are the most recent evidence, researchers say, of an ancient process that created the 3,mile-long Hawaiian-Emperor Seamount Chain.
What the scientists found there is "Pele red" in color: Iron oxide, or rust, come to life. Along the Hawaiian-Emperor Seamount Chain at Loihi Seamount--an active submarine volcano 22 miles off the coast of the island of Hawaii and 3, feet below sea level--the biologists are conducting research on Zetaproteobacteria, life-forms that use iron as an energy source.
Zetaproteobacteria form iron-rich microbial mats on Loihi's flanks. Hydrothermal vents, seafloor geysers that support microbial oases, line Loihi's summit. The hot fluids spewing from the vents contain high levels of iron, turning Loihi's underwater slopes an unusual, and characteristic, orange-red.
For example, iron is the oxygen-carrying component of hemoglobin in blood. What's less known about iron, he says, "is that it can support the growth of an array of microbes. Seismic tremor levels at the summit are elevated to nearly moderate levels. Summit sulfur dioxide emission rates have remained elevated at more than four times background levels since early January Earthquakes were located primarily beneath the general summit area, the southwest rift zone, and the south flank faults.
Lava from the Thanksgiving Eve Breakout TEB flow, erupting from fissure D of the July 21 eruption, continues to flow through what remains of the Royal Gardens subdivision and across the coastal plain. The Waikupanaha delta has grown to be more than m ft in width and has several entry points. The public should be aware that the ocean entry areas could collapse at any time, potentially generating large explosions in the process.
The steam clouds rising from the entry areas are highly acidic and laced with glass particles. Do not venture onto the lava deltas and benches. Even the intervening beaches are susceptible to large waves suddenly generated during delta collapse; these beaches should be avoided. This pahoehoe flow is being fed from the end of the rootless shield complex constructed southeast of the TEB vent since November.
An area of persistent breakouts on the northeast side of the shield complex also continues to produce small flows. These northeast-directed flows are restricted to a broad, flat area on the south side of Kupaianaha. With surgical precision, small crystals are extricated from every glassy morsel and impeccably polished for electron microscope analysis. The glassy rock matrix provides eruption temperatures, because magma composition changes as it cools and crystals form.
The composition of the crystals also varies according to temperature and can be used to track the path that magma takes to the surface. By analyzing tiny pockets of glass that are occasionally entrapped by crystals as they form called melt inclusions , our petrologist has been gleaning some of Madame Pele's best-kept secrets.
Sulfur is one of the last gases to emerge from basalt magma as it approaches the surface. The chemistry of lava samples from this eruption shows that the fountains ruptured through magma that had been sitting underground in this area since eruptions in the s. Beneath the billowing summit plume, hot and corrosive magma is roiling to the surface, disgorging its gases, and swallowing and regurgitating newly formed crust. Lava levels rise and fall like a barometer in response to summit inflation and deflation.
Slowly but surely, magma consumes the walls of the vent itself.
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