new tectonic plate
Scientists discovered a new tectonic plate on the coast of Ecuador. By adding another plate total 57 plates in the earth’s tectonic puzzle. Scientists named the new microplate, Malpelo, analyze the trio of other plates in the eastern Pacific Ocean. The new tectonic plate is the 57th plate.
The Pacific lithospheric plate roughly forms the Ring of Fire, a region of volcanic activity in earth’s mantle. Which behaves like a fluid over geologic time. There are many small plates that fill the gaps between the larger plates, and the Pacific Plate meets two other smaller plates, the Cocos and Nazca, west of the Galapagos Islands.
Researchers can estimate the speeds of plates by measuring the rates of seafloor spreading and the angles of plates slip by each other. According to Rice geophysicist Richard Gordon, when adding the angular velocities to the three plates, they ought to sum to zero. While, the velocity doesn’t sum to zero at all. It sums up to 15 millimeters a year, which is huge.
Panama transform fault
To find its boundaries, researchers extracted a record of multibeam sonar soundings. Deviation in the data suggested the presence of a new eastern plate known as Panama transform fault, a region to be part of the Nazca plate. The study revealed the presence of a diffuse plate boundary between the Panama fault east to the coasts of Ecuador and Colombia.
Earthquakes along diffuse boundaries tend to be smaller and less frequent than along transform faults. There was little information in the seismic record to indicate this one’s presence.
With the Malpelo, the new circuit still doesn’t close to zero and the contracting Pacific Plate isn’t enough to account for the difference either, researchers said. The non-closure around this tri-junction goes down not to zero, but only to 10 or 11 millimeters a year.
More information: [Geophysical research letters]