Thales around 600 BC postulated that water under the earth could be a physical cause for earthquakes has now been recognised in the source process of peculiar signals that are so weak that they have only newly been detected in the 21st century.
The FP6 NEST project, THALES WAS RIGHT, was set up to detect new types of seismic signals, as well as deep structural images that are relevant to the problem, being possible heralds of mega-thrust earthquakes.
Megathrust earthquakes occur at subduction zones at destructive plate boundaries (convergent boundaries), where one tectonic plate is forced (or subducts) under another. Due to the shallow dip of the plate boundary, which causes large sections to get stuck, these earthquakes are among the world's largest, with moment magnitudes (Mw) that can exceed 9.0. Since 1900, all five earthquakes of magnitude 9.0 or greater have been megathrust earthquakes; in fact, no other type of known tectonic activity can produce earthquakes of this scale.
Chile 2010 Megathrust Earthquake, The Nazca Plate is subducting under the South American Plate. This movement causes seismicity and volcanism throughout Chile.
Novel methods, techniques and instruments were used for observation in the two European subduction zones, the Western Hellenic and Lesser Antilles Arc in the hope to detect abnormal signs of an earthquake and reduce the risk that Europeans will be taken by surprise as the world was in 2004 by the Sumatra-Andaman earthquake.
The occurrence only few months ago of the catastrophic Sumatra M9 earthquake was unexpected; hence Thematic Priorities of FP6 could not have included study of hazard of that type, which this occurrence now proved possible against previous state-of-the-art wisdom. This project presents a scientific measurement approach for the detection of new types of seismic signals, as well as deep structural images that are relevant to the problem, being possible heralds of mega-thrust earthquakes.
This will be applied in the two European subduction zones, the Western Hellenic and Lesser Antilles Arc, that may be prone for M>8 earthquakes as they share characters of the Sumatra-Andaman case. These water-related phenomena, deep seismic tremor and silent earthquake, were recently discovered in Japan and NW US subduction zones, where advanced technologies and methods have been applied.
This will be applied in the two European subduction zones, the Western Hellenic and Lesser Antilles Arc, that may be prone for M>8 earthquakes as they share characters of the Sumatra-Andaman case. These water-related phenomena, deep seismic tremor and silent earthquake, were recently discovered in Japan and NW US subduction zones, where advanced technologies and methods have been applied.
They were reported to have their source region close to the inter-plate subduction boundary, the mega-thrust fault plane, where possible water content has been revealed by deep structural seismic images. Importantly, these transient signals, are observed in advance of the major M>8 earthquakes expected there. They might in case be considered as possible silent heralds of mega-thrust earthquakes and monitored.
The THALE project is to apply to these two European subduction areas advanced studies of activity and structure, with novel High-Tech observation means. Among them: Broad-Band Ocean Bottom Seismometers just developed that may detect these new transient signals, an opportunity of seismic reflection imaging with the French academic seismic ship for the Antilles, novelty of a joint integrated approach possible by merging forces at European scale. This scientific measurement approach may open the way to monitoring evolution, with high-yield/high-risk possible societal impact for hazard preparedness and mitigation.
The THALE project is to apply to these two European subduction areas advanced studies of activity and structure, with novel High-Tech observation means. Among them: Broad-Band Ocean Bottom Seismometers just developed that may detect these new transient signals, an opportunity of seismic reflection imaging with the French academic seismic ship for the Antilles, novelty of a joint integrated approach possible by merging forces at European scale. This scientific measurement approach may open the way to monitoring evolution, with high-yield/high-risk possible societal impact for hazard preparedness and mitigation.
Thales attempted to explain natural phenomena without reference to mythology and was tremendously influential in this respect. Almost all of the other pre-Socratic philosophers follow him in attempting to provide an explanation of ultimate substance, change, and the existence of the world—without reference to mythology. Those philosophers were also influential, and eventually Thales' rejection of mythological explanations became an essential idea for the scientific revolution. He was also the first to define general principles and set forth hypotheses, and as a result has been dubbed the "Father of Science"
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