In a surprise finding, undersea hot lava is baking ocean sediments and releasing greenhouse gases.
THE GIST
- Lava injected into deep sea sediments is baking sediments and driving out greenhouse gases.
- The discovery reverses what was thought of as a carbon sink into a carbon source.
- Ancient versions of the same situation have been blamed for past global climate changes.
A deep-sea volcano spews lava. Research shows lava from such eruptions end up baking ocean sediment and releasing greenhouse gases. Click to enlarge this image. One of the places where Nature was thought to suck up and bury atmospheric carbon may actually be doing just the opposite, according to new research on the volcanics of deep-sea ridges.
Seismic profiles of the rifting Guaymas Basin in the Gulf of California show molten rock from a deep-sea ridge squeezing far and wide as "sills" of magma into the layers of ocean floor sediments. The sediments
, which are loaded with organic debris, are baked by the magma and so release vast amounts of greenhouse gases.
The discovery has big implications for calculating the Earth's current carbon budget, as well as for how past climates were thrown in to disarray by "intrusive" volcanic activity beneath the seafloor -- a place that had always previously been considered a carbon sink, not a carbon source.
"It was one of those 'Ahah!' moments," said researcher Daniel Lizarralde of the Woods Hole Oceanographic Institution, describing the discovery of the sills in the seismic data.
What especially surprised the researchers was how far the magma sills were located from the narrow ridge where magma is typically found at most ocean floor spreading centers. In the Guaymas Basin the sills of magma were not just a few kilometers (1.8 miles) away from the spreading center ridge, as expected, but up to 50 kilometers (31 miles) away. That vastly increases the volume of sediments the hot rock can cook and from which methane and other carbon-rich gases can be released.
Lizarralde and his colleagues published their discovery in the Nov. 14 issue of the journal Nature Geoscience.
"Sills derived from intrusive volcanism in sedimentary basins have been linked to huge natural methane fluxes in the past," commented David Goldberg of the Lamont-Doherty Earth Observatory. In a separate article in the same issue of Nature Geoscience, Goldberg cites, for example, the 55-million-year-old sills of the Norwegian margin, which is suspected of having caused global climate change.
Goldberg also explains that what makes these sills such potent sources of carbon gases is the fact they are buried. Thick blankets of sediment allow the magma to bake the buried organic material at very high temperatures and drive off ten times more carbon dioxide than if the magma had just poured out onto the seafloor.
All that gas buoys up through the sediments and into the ocean, heating up the deep waters. Methane that is release can stimulate deep sea biological activity.
Exactly how much carbon these sills and others like them in small ocean basins elsewhere are contributing to the atmospheric carbon is still not known, said Lizarralde. For one thing, this is the first place such wide-ranging sills have been discovered. And then there is the question of how much of the carbon-rich gases are recaptured by deep-sea organisms -- and so never reached the ocean's surface.
"We don't know how much is immediately taken out by seafloor fauna," said Lizarralde. That will take a lot more deep sea exploration to determine.
Seismic profiles of the rifting Guaymas Basin in the Gulf of California show molten rock from a deep-sea ridge squeezing far and wide as "sills" of magma into the layers of ocean floor sediments. The sediments
, which are loaded with organic debris, are baked by the magma and so release vast amounts of greenhouse gases.
The discovery has big implications for calculating the Earth's current carbon budget, as well as for how past climates were thrown in to disarray by "intrusive" volcanic activity beneath the seafloor -- a place that had always previously been considered a carbon sink, not a carbon source.
"It was one of those 'Ahah!' moments," said researcher Daniel Lizarralde of the Woods Hole Oceanographic Institution, describing the discovery of the sills in the seismic data.
What especially surprised the researchers was how far the magma sills were located from the narrow ridge where magma is typically found at most ocean floor spreading centers. In the Guaymas Basin the sills of magma were not just a few kilometers (1.8 miles) away from the spreading center ridge, as expected, but up to 50 kilometers (31 miles) away. That vastly increases the volume of sediments the hot rock can cook and from which methane and other carbon-rich gases can be released.
Lizarralde and his colleagues published their discovery in the Nov. 14 issue of the journal Nature Geoscience.
"Sills derived from intrusive volcanism in sedimentary basins have been linked to huge natural methane fluxes in the past," commented David Goldberg of the Lamont-Doherty Earth Observatory. In a separate article in the same issue of Nature Geoscience, Goldberg cites, for example, the 55-million-year-old sills of the Norwegian margin, which is suspected of having caused global climate change.
Goldberg also explains that what makes these sills such potent sources of carbon gases is the fact they are buried. Thick blankets of sediment allow the magma to bake the buried organic material at very high temperatures and drive off ten times more carbon dioxide than if the magma had just poured out onto the seafloor.
All that gas buoys up through the sediments and into the ocean, heating up the deep waters. Methane that is release can stimulate deep sea biological activity.
Exactly how much carbon these sills and others like them in small ocean basins elsewhere are contributing to the atmospheric carbon is still not known, said Lizarralde. For one thing, this is the first place such wide-ranging sills have been discovered. And then there is the question of how much of the carbon-rich gases are recaptured by deep-sea organisms -- and so never reached the ocean's surface.
"We don't know how much is immediately taken out by seafloor fauna," said Lizarralde. That will take a lot more deep sea exploration to determine.
Dave, the scientific community is not divided, there are just a few qualified scientists, as there will be on any issue, who seem unconvinced, and a lot more very vocal unqualified people who just deny the science.
Science is about finding new data and research will never be complete. But this article does not point to any error in current theories. Lava may be driving out GHGs but if this is so it has been the case for billions of years and can't account for much of the current, mostly manmade, rise.
This is just an observation, but how can you have a concensus on Anthropogenic Global Warming when you as a scientific community are both divided on the issue of AGW itself, and as well are constantly finding 'new data' that gives every indication, every time, that your current findings are erronneous and incomplete? How about you just come out and say it...no matter how much data you collect, you cannot have it all, and therefore cannot make a sweeping, broad statement justifying the immense carbon taxes collected effectively raping the nations of the world? (We're talking Trillions of dollars here in carbon credits, et al...money which is essentially leaving the economy where it is desperately needed, and being moved offshore where it is useless). I mean, if you have discovered this new data, then obviously it is not in your current models that you have used to fool the world with...which means your AGW figures are off by that much with this new information, and this isn't nearly the first article I've read regarding 'new discoveries' that affect the overall calculations. I mean, it's not like this new data wasn't applicable before it's discovery right? I am appalled at the disregard the government bodies of the 'free' world are displaying when the scientific community itself is in an uproar regarding the sheer level of monetary manipulation and attempt by the globalists to hijack this AGW idea to further their agenda. If you doubt that they care not about the environment, consider that the only thing they have accomplished is to create a tax whereby continued pollution at the same level is ok as long as it is paid for monetarily...how does that solve this 'worldwide problem of AGW'? It doesn't. Now you MUST take a moment and ask yourself....exactly what DOES it do?
Dave do you care enough to actually learn what the studies say?