Researchers at the University of Tskuba have developed a state-of-the-art model that has found the complexity of rupture processes even in simple oceanic faults.
Researchers at Car University in Cuba used seismic data from around the world to build a 2020 model of the Caribbean Earthquake. Ocean deformation faults are generally considered to be linear և and have been widely used in seismic dynamics studies. However, the research team found that high complexity of the rupture velocity և direction can occur even in a system of supposedly simple linear malfunctions.
On January 28, 2020, a magnitude 7.7 earthquake shook the Caribbean Sea in the Caribbean, east of the Orienta Transformation Fault. It caused a minor tsunami at a height of 0.11 m, which was felt far from the borders of Florida.
A research team at Earthquake University in Cuba has developed a new method of ultimate fault reversal to build models based on the seismic wave data of earthquake observation stations. This new approach to data usage is taking a more flexible approach to solving fault geometry. Instead of relying on previous assumptions, the components of the fault are evaluated separately in a larger model և in time և in space, allowing us to observe the evolution of all possible faults. The team wanted to use the Caribbean Earthquake to help understand the guilt processes that occur during those shallow ocean tremors.
“Some cases of complex earthquake dynamics have been reported recently in previous earthquake studies, raising the question of whether we model them correctly even in supposedly simple fault systems,” said study author Professor Yuji Yagin. “Preliminary monitoring of this January event suggested changes in the tide between two stations at the same distance from the epicenter, suggesting that the complexity of this fault has yet to be explored.”
This was a great opportunity to test a new method developed by the team that used data from 52 seismic stations to build a detailed model of the geophysical processes in an earthquake-induced fault.
“The results showed a complex fault during the earthquake caused by the bending of the fault, which led to changes in the velocity and direction of the rupture, which were found in the observation data,” explains the author Professor Ryo Okuvaki. “These oscillations triggered several successive ruptures that occurred along a 300-kilometer-long fault.” The modeling approach also allows some suggestions to be made about the possible occurrence of a landing after the earthquake և the surrounding seabed.
These findings reveal that simple: linear ocean transformation faults can be much more complex than previously thought, and therefore require a more comprehensive approach to earthquake modeling. This work will shed light on the possible interaction of the evolution of the ocean floor around the boundary of an earthquake fault motion: transformation.
Reference. “Tira Tadapansavut, Rio Okuvaki, Yuji Yagi և Shinji Yamashita, December 6, 2020 Geophysical research letters,
DOI: 10.1029 / 2020GL090899: