The United States Geological Survey reported a Magnitude 4.7 Earthquake at a depth of 9.9 km about 87 km northeast of the city of Zeya in Amur Oblast (Amur State) in the Russian Far East, slightly after 1.25 am on Friday 27 October 2017, local time, (slightly after 4.25 pm on Thusday 26 October GNT). There are no reports of any damage or casualties associated with this event, but it was felt locally.
The approximate location of the 27 October 2017 Amur Earthquake. USGS.
The Zeya area lies on the northern part of the Amurian Plate, hich underlies the southwest part of the Russian Far East, as well as northeatern China, the Korean Peninsula and southern Japan. The Amur Plate is moving southeast with regard to the Eurasian Plate, which lies to the north, creating a boundry between the plates which is both transform (i.e. the plates are moving sideways relative to one-another in places, with the Eurasian Plate moving west while the Amurian plate moves east, and divergent (with the plates being drawn apart, with the Eurasian Plate moving northward while the Amurian Plate moves to the south). These processes are not smooth, with the rocks of the two plates continuously sticking together then cracking apart as the pressure caused by the movement of the plates becomes to great, creating shockwaves we experience as Earthquakes.
Map of Plate Framework in the Northeast Asia. Study area is depicted by open red box. Boundaries of the Okhotsk (OK) and Amur (AM) plates are shown. Surrounding plates include Eurasia (EU), North America (NA), Pacific (PA), Philippine Sea (PS), and Yangtze (YA). Black vectors give model velocities (with numbers in mm/a) relative to plate whose identifier is underlined. Black circles are locations of Euler poles. Akira Takeuchi (2013).
Witness accounts of Earthquakes can help geologists to understand these events, and the structures that cause them. The international non-profit organisation Earthquake Report is interested in hearing from people who may have felt this event; if you felt this quake then you can report it to Earthquake Report here.
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