Japan's 311 earthquake is located in the waters of northeastern Japan. It has a magnitude of 10 kilometers and a magnitude of 10 kilometers. The destructive power is extremely great, and Fukushima Nuclear Power Plant was destroyed.
1 strong earthquake moved Japan's Honshu Island to the east about 3.6 meters, and ground axis moved 25 cm, speeding up the earth's rotation by 1.6 microseconds.
, located in the northwest of the epicenter, moved about 5.3 meters to the southeast of the epicenter, and sank about 1.2 meters. This is the largest crustal change record in Japan's history. The Korean Peninsula also moved eastward by 5.16 cm; the northern part of my country also moved eastward by a few millimeters.
This earthquake was caused by vertical movement between plates rather than horizontal movement, and was an anti-fault fault, which triggered a tsunami.
large-scale crustal changes are continuously reflected due to earthquakes. It is not that the entire area rises or sinks together, but that a very complex phenomenon has occurred. Future changes are unpredictable.
Satellite Gps shows that foundation settlement occurred in the northeast to Kanto region, deflecting eastward. The Muharu Peninsula in Miyagi Prefecture moves about 5 meters eastward and settles more than 1 meter.
The foundation on the Sea of Japan continued to sink, and Yuzawa City, Akita Prefecture has sinked nearly 30 cm. The
earthquake is located at the junction of the North American plate subduction of the Pacific plate, but at the same time there is a downward subduction of the Philippine plate toward the eastward direction, and it also faces the squeeze of the Eurasian plate toward the east.
From the above figure, Japan is mainly threatened by three earthquake zones: Hokkaido -Kamchatka (Mw ≥ 9.2 earthquake hazard zone), Northern Mariana Islands (Mw 8.8 earthquake hazard zone) and Ryukyu Islands - Taiwan Island (Mw 9.0 earthquake hazard zone).
311 earthquake belongs to the Hokkaido-Kamchatka region and is located in the North American plate.
underground structure simplified map, but there are multiple plates in the area superimposed at the same time, which may form many fracture fragments and various forms of faults.
311 major earthquake is an anti-fault type earthquake. The seismic fault of the Wenchuan earthquake is also an anti-fault. This is a type of fault in geological structure. Its movement form is the rise of the upper plate and the decline of the lower plate. The surface damage is more serious than that of the regular fault and strike-slip fault.
