Japanese researchers examined a powerful earthquake near Mandalay, Myanmar, resulting from the Sagaing Fault’s movement. With a magnitude of 7.7, this quake was the largest since recorded data began. Insights from the analysis highlight historical earthquake patterns and the implications of fault dynamics for regional risk assessments.
Recently, Japanese seismic researchers analyzed a significant earthquake that struck near Mandalay, Myanmar. Professor Tsutsumi Hiroyuki from Doshisha University highlighted that the quake, with a magnitude of 7.7, resulted from a 200-kilometer section of the Sagaing Fault shifting sideways, marking the strongest seismic event since detailed records became available.
Professor Tsutsumi further explained that the Sagaing Fault, roughly 1,500 kilometers long, was formed by the Indo-Australian plate’s movement toward the Himalayas. Historical records indicate that magnitude 7 quakes have occurred along this fault intermittently since the 1800s. He noted that the last significant quake in the Mandalay area took place in 1839, suggesting a pattern of seismic activity with historical intervals of 100 to 200 years.
Yagi Yuji, a professor from the University of Tsukuba, analyzed seismic waves to understand the quake’s fault rupture dynamics. He reported that the rupture began at the epicenter, extending south for approximately 10 seconds before spreading north and south for a total of about 70 seconds. Such rapid rupture propagation may heighten destructive potential, particularly as it could exceed the speed of seismic S waves.
Professor Yagi cautioned that the unusually fast rupture speed could generate intensely destructive seismic waves, posing risks to bordering regions such as Thailand. He emphasized that parts of the fault remain unruptured, suggesting ongoing strain accumulation that could lead to future seismic events, highlighting a need for ongoing vigilance.
The analysis of the recent seismic activity near Mandalay, Myanmar, reveals essential insights into the behavior of the Sagaing Fault. Experts Tsutsumi and Yagi emphasize the significance of understanding historical patterns of earthquakes and the implications of rapid fault rupture propagation. Their research underscores the importance of preparedness for potential aftershocks and future seismic threats in the region.
Original Source: www3.nhk.or.jp
