It's (not) volcanoes: WUWT ponders the implications of newly discovered old seamounts

Gravity gradient model, Mid-Atlantic Ridge; green dots are earthquakes of at least magnitude 5.5
Credit: David Sandwell, SIO

There is a new paper in Science this week about the latest ocean topographic mapping effort. A team of researchers led by David T. Sandwell "combined new radar altimeter measurements from satellites CryoSat-2 and Jason-1 with existing data to construct a global marine gravity model that is two times more accurate than previous models." As the editor's summary stated:

Detailed topographic maps are available for only a small fraction of the ocean floor, severely limited by the number of ship crossings. Global maps constructed using satellite-derived gravity data, in contrast, are limited in the size of features they can resolve. Sandwell et al. present a new marine gravity model that greatly improves this resolution (see the Perspective by Hwang and Chang). They identify several previously unknown tectonic features, including extinct spreading ridges in the Gulf of Mexico and numerous uncharted seamounts.  

North Atlantic Ocean gravity gradient model showing plate tectonic history of rifting continents.
Credit: David Sandwell, SIO

The paper indicated that this research will help improve the estimates of sea-floor depth in the 80% of the oceans having no depth soundings, and will greatly help scientists add to knowledge of ocean tectonic processes.

Brittle stars and deep-sea corals cover
a known seamount in the western Pacific Ocean.
Credit: NOAA

If you are interested in the subject, you can learn more about the work at the NSF website and read the paper at Science (subs required).

The press release was also published at ScienceDaily.com.

The Hwang and Chang perspective mentioned in the editor's summary can be read here, though you might need a subscription to Science.

It's (not) undersea volcanoes

Whenever the topic of volcanoes under the ocean comes up, you're bound to get deniers claiming global warming is caused by undersea volcanoes. Or something along those lines. (The under-sea volcanoes notion isn't that uncommon, but it is pretty silly. It doesn't make the top 176 denier memes at SkepticalScience.com.)

A moment's reflection would stop this denier meme in its tracks. Deniers are not good at reflection.