A group of researchers from the University of Washington on the Cascadia Fault With regard to the outflow of fluids observed on the seafloor, no cause-and-effect relationship is established for generating a strong-magnitude earthquake, the National Polytechnic geophysicist explained in a statement Tuesday.

The Ecuadorian geological body explains that the phenomenon has generated a series of rumors, especially on social networks, based on two images from the publication, titled “Fluid Resources and Overpressure Within the Central Cascadia Subduction Zone Revealed by a Warm, High-flux Seafloor Leak”.

This publication analyzes the origin of the fluids in a study off the west coast of the United States, in the Cascadia subduction zone.

Some media have reported an alleged relationship between the outflow of fluid from the ocean floor and a strong earthquake greater than 9 on the Richter scale in the subduction zone, located off the coast of Oregon, in the North Pacific Ocean.

fluid outlet

The outflow of fluids onto the sea floor has been commonly reported for decades, the local statement explains. This outflow of fluids has been observed both in the expansion zones, where new oceanic crust is formed, and the circulation of fluids that generates the well-known black vents.

Also, the outflow of fluids has been observed in places where the oceanic crust is consumed (subduction zones), that is, where an oceanic crust goes under another plate, as is the case off the coast of Ecuador. the Nazca Plate is subducting beneath the South American Plate. In this process, the Nazca Plate, on the one hand, carries sediments, which can accumulate and compress, in what is called the accretion prism, at the edge of the South American Plate; this compression causes compaction of the sediments and in turn overpressurizes them. This is one of the ways in which the liquids are expelled from the interior of the sediments, creating a kind of chimney through which the liquids escape.

Another source of overpressure generation and fluid expulsion is related to fluids being assimilated into the oceanic crust (into structures and minerals) on their journey to the subduction zone. The oceanic crust, which is submerged, increases its temperature due to the increase in depth and releases fluids due to mineralogical changes. These fluids migrate to more superficial sectors and are released from the ocean floor.

At the fluid outlet sites, structures known as “pockmarks” form, which are shaped like small craters.

According to the geophysicist, off the coast of Ecuador in the first four months of 2022 The Franco-Ecuadorian-German cooperation project carried out a marine geophysics campaignin which he detected different fluid outlet areas using a multibeam probe.

Currently, new studies point to the fact that the presence of fluids would cause slow landslides (duration of days, weeks or months) on the faults, implying no strong-magnitude earthquakes. With this explanation, the geophysicist reiterates that there is no support to say that the outflow of fluids is a precursor to the occurrence of a strong earthquake.