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The 1990 Vrancea earthquakes were three earthquakes on 30 and 31 May 1990 measuring 6.7 and 6.1 on Richter scale, that struck the Romanian county of Vrancea, on two consecutive days.〔(【引用サイトリンク】title=Significant earthquakes of the world, 1990 )〕 Severe damage in the Bucharest-Brăila-Brașov area was reported and dozens of casualties in Romania and neighbouring Moldova, Ukraine and Bulgaria. The seismic doublet of May 1990 consisted of two mainshocks occurred at a distance of only 13 hours. The first mainshock took place in the afternoon of 30 May 1990, at 13:40:06 (local hour). The epicenter was located in the northeastern part of the Vrancea Mountains (), at a depth of 89 km. The earthquake had a magnitude of MGR = 6.7 or Mw = 6.9, the intensity in the epicentral area being of VIII degrees on the Mercalli intensity scale, and VII degrees in Bucharest.〔 On the morning of 31 May 1990, at 3:17 (local hour), occurred the second mainshock, at a depth of 79–86 km, having the magnitude MGR = 6.1 or Mw = 6.3.〔 The event was felt in the epicentral area with an intensity of VII degrees on the Mercalli intensity scale, and VI degrees in Bucharest; likewise, the quake was felt strong enough in Dobrogea. In the USGS EXPO-CAT database it is estimated that during this earthquake 355,000 people were exposed to intensity VII, of which around 61% were in rural areas. == Aftershocks == The first mainshock was followed by several aftershocks with magnitudes ranging between 3–4.5 degrees on the Richter scale, reported in the afternoon and evening of 30 May.〔 On the morning of 31 May 1990 continued the replicas of the two mainshocks. Thus, at 7:48 (local hour) occurred a replica of magnitude 4.7, felt in Bucharest with an intensity of IV degrees on the Mercalli intensity scale. Other replicas of lower magnitudes continued to occur in Vrancea until the end of June 1990, in the depth floor of 70–90 km.〔 Secondary seismic movements, at the same depth, were recorded and later, until October 1990. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「1990 Vrancea earthquakes」の詳細全文を読む スポンサード リンク
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