Terrestrial peculiarity, the crust of our planet is divided into numerouswho under the impetus of Mantle and major tectonic processes: ocean and subduction. If is now consensus, but there are several models detailing many configurational variations at the plate boundary level.
The tectonic plates, pieces of the puzzle with blurred contours
Because thecan be compared to a jigsaw puzzle in which the outlines of the pieces are hardly known. However, the exact definition of the plate boundaries is an essential point in order to carry out accurate reconstructions of the plates plates and understand how they came , during the major tectonic cycles that the earth is experiencing. In addition, plate boundaries always represent areas of intense deformation associated with tectonic or magmatic processes. They may be extended – thus marking a zone of oceanic accretion – compressing – in which case they may be associated with a subduction zone or mountain range – or in shear. The case in point is the San Andreas Fault in the United States, an area prone to very large earthquakes.
Accurate knowledge of the properties of these distinct plate boundaries and accurate definition of the extent of the deformation zone are essential to assess the geohazards faced by the populations living in these regions.
New knowledge finally integrated into tectonic maps
A research team from the University of Adelaide, Australia, has therefore dealt with thethree new world maps: configuration of the tectonic plates, configuration of the main geological provinces and configuration of the mountain ranges (new or old). That is a very complete and essential to conduct many studies.
The tectonic plate map has not been updated since 2003. Since then, however, much progress has been made, particularly in defining new microplates such as that of Macquarie in southern Tasmania, but also the Capricorn microplate which separates the Indian and Australian plates. The big novelty, however, is on the west coast side of North America, where the active deformation zone, attributed to the San Andreas and Queen Charlotte faults, has been enlarged compared to previous models. It now stretches over 1,500 km.
The new maps also better illustrate the large zone of deformation affecting Central Asia and associated with the punching of India into the interior of the Eurasian continent. This big collision that atand the highest peak in the world, Everest, indeed affects a very large area in Asia that is regularly subject to earthquakes.
Better integration of seismic and volcanic events
The results of the study were published in the journal. By integrating a large amount of data ( earthquakes, fault lines, from and magnetic anomalies, geochronology, etc.), these new maps allow us to better explain the distribution and origin of 90% of earthquakes and 80% of volcanoes over the last two million years. In comparison, older models captured only 65% of earthquakes.