The Meiji Seamount is an underwater volcanic mountain in the Pacific Ocean. It is classified both as an underwater volcano and as a seamount (underwater volcano, seamount) and forms part of the long volcanic trail known as the Hawaiian–Emperor seamount chain (Hawaiian–Emperor seamount chain) in the Pacific (Pacific Ocean). Meiji is considered extinct; the most commonly cited estimate places its last volcanic activity at about 62 million years ago.

Physical characteristics

Meiji has a broad, flattened summit characteristic of a guyot or tablemount. That flat top indicates a period when the volcano was eroded near or at sea level before the seafloor cooled and subsided, leaving the summit well below the surface. Geomorphology and sampled rocks show the mountain is built from volcanic flows and later covered by sediments and marine deposits.

Geological history and origin

The Hawaiian–Emperor chain, including Meiji, formed as the Pacific Plate moved over a relatively stationary mantle hotspot. The chain preserves a time-progressive record of volcanic construction. Over millions of years, individual volcanoes become dormant as they move off the hotspot, erode at sea level and then sink with the cooling lithosphere to form guyots.

Scientific importance and study

Meiji and neighboring seamounts are important for understanding plate motions, hotspot dynamics and ancient sea levels. Researchers examine rock samples, magnetic data and sediment cores to reconstruct eruption ages, paleolatitudes and subsidence histories. Typical lines of study include:

  • Radiometric dating of igneous rocks to determine timing of activity
  • Paleomagnetic measurements to infer past plate positions
  • Seismic and bathymetric mapping of summit morphology

Names, distinctions and legacy

The feature is commonly called Meiji Guyot because of its flat top; the geological term guyot (or tablemount) describes such drowned, flattened seamounts. The seamount’s name honors Emperor Meiji of Japan (Emperor Meiji), following conventions of naming Pacific features after historical figures or explorers. As an extinct member of the chain, Meiji serves as a geological marker for early Cenozoic tectonic and volcanic processes.