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1899 Ceram Earthquake
On 30 September 1899 the island of Ceram, Dutch East Indies, was struck by an Ms 7.8 earthquake which was accompanied by a 10-meter landslide-induced tsunami. According to the Batavian Magnetic and Meteorological Observatory, the shock occurred at 01:42.2 AM Amahei local time.Dr. R. D. M. Verbeek, ''Kort verslag over de aard- en zeebeving op Ceram, den 30sten september 1899'' (Batavia Landsdrukkerij, 1900) p. 1–11. The study about the quake and its effects was published by Dr. R. D. M. Verbeek in an article named ''Short Report about the earth- and sea-quake in Ceram, the 30th September 1899'', which serves as the only extensive source on this earthquake. Earthquake and tsunamis The Ceram earthquake is ranked among the tectonic quakes. The epicenter of the quake is shown in Figure 1. From there the quake spread in all directions. The most forceful spread went west and east, presumably through an old crack or tear in the Earth's crust. The 1899 Ceram earthquake had nothing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surface Wave Magnitude
The surface wave magnitude (M_s) scale is one of the magnitude scales used in seismology to describe the size of an earthquake. It is based on measurements of Rayleigh surface waves that travel along the uppermost layers of the Earth. This magnitude scale is related to the local magnitude scale proposed by Charles Francis Richter in 1935, with modifications from both Richter and Beno Gutenberg throughout the 1940s and 1950s. It is currently used in People's Republic of China as a national standard (GB 17740-1999) for categorising earthquakes. Recorded magnitudes of earthquakes through the mid 20th century, commonly attributed to Richter, could be either M_s or M_L. Definition The formula to calculate surface wave magnitude is: :M_s = \log_\left(\frac\right)_ + \sigma(\Delta)\,, where A is the maximum particle displacement in surface waves (vector sum of the two horizontal displacements) in μm, T is the corresponding period in s (usually 20 2 seconds), Δ is the epi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
