The 21 May 2014 Mw 5.9 Bay of Bengal Earthquake: Macroseismic Data Suggest a High-Stress-Drop Event

Abstract

Online Material: Tables of locations and associated intensity values. A modest but noteworthy M w 5.9 earthquake occurred in the Bay of Bengal beneath the central Bengal fan at 21:51 Indian Standard Time (16:21 UTC) on 21 May 2014. Centered over 300 km from the eastern coastline of India (Fig. 1), it caused modest damage by virtue of its location and magnitude. However, shaking was very widely felt in parts of eastern India where earthquakes are uncommon. Media outlets reported as many as four fatalities. Although most deaths were blamed on heart attacks, the death of one woman was attributed by different sources to either a roof collapse or a stampede (see ![Graphic][1] Table S1, available in the electronic supplement to this article). Across the state of Odisha, as many as 250 people were injured (see ![Graphic][2] Table S1), most after jumping from balconies or terraces. Light damage was reported from a number of towns on coastal deltaic sediments, including collapsed walls and damage to pukka and thatched dwellings. Shaking was felt well inland into east‐central India and was perceptible in multistoried buildings as far as Chennai, Delhi, and Jaipur at distances of ≈1600 km (Table 1). Figure 1. The white star represents the location of the 21 May 2014 earthquake. Open circles mark the locations of M w>5.0 instrumentally recorded earthquakes in the Bay of Bengal basin since 1964. Locations and dates of other events are also indicated (black stars): 2011 Dalbandin, 2011 Sikkim, and the 1934 Balochistan earthquake near the Iran–Pakistan border. Source depth estimates for the 2014 event range from 50 km (U.S. Geological Survey [USGS] monthly Preliminary Determination of Epicenter Bulletin ) to 60–85 km (Singh et al. , 2015). View this table: Table 1 Magnitude Types Used in This Report In the days following the earthquake, we collected accounts from conventional news outlets as well as social media. Using … [1]: /embed/inline-graphic-1.gif [2]: /embed/inline-graphic-2.gif