I just have time today to highlight the discovery of what may be the single largest volcano on Earth, roughly comparable in size to Olympus Mons on Mars.
Sager et al. (2013) report in November’s Nature Geoscience that the Tamu Massif, a major component of Shatsky Rise, an oceanic plateau in the northwestern Pacific, is a single massive shield volcano emplaced within a relatively short period of time, possibly during a single pulse of magmatism, in the latest Jurassic to earliest Cretaceous. Seismic profiles and rock samples reveal the dome-shaped edifice to be composed of thick lava flows that can be traced over distances of 5 to 20 km with anomalously low slopes attributed to the high effusion rates.
This extraordinary discovery provides further evidence that the scale and rates of geological processes in the past often dwarf those we are familiar with in the present.
Sager W.W., Zhang J., Korenaga J., Sano T., Koppers A.A.P., Widdowson M. and Mahoney J.J. 2013. An immense shield volcano within the Shatsky Rise oceanic plateau, northwest Pacific Ocean. Nature Geoscience 6:976-981.