A severely felt earthquake of Mw 5.5 occurred on 22 June 2020, in the Champhai district of Mizoram, North East Region (NER) of India, in the vicinity of the Indo-Myanmar subduction zone. This earthquake was associated with a swarm type of activity; six earthquakes of Mw 4.0–5.1 and some 16 earthquakes of Mw 3.0–3.9 occurred almost within two months like a swarm which caused much panic in the Mizoram state and neighbouring region. The mainshock of Mw 5.5 was preceded by an earthquake of Mw 5.1 on the previous day, 21 June 2020, in the capital city Aizawl, ~ 70 km northwest of Champhai. All of these events originated at shallow depth (~ 10–30 km) and occurred in the intra-plate zone of the subducting Indian plate. Fault plane solution of the mainshock indicates strike-slip faulting that matches fairly well with the transverse Mat Fault in the Outer Indo-Burma Wedge (OIBW). Macroseismic investigation of the mainshock at some 46 sites shows the maximum intensity of VIII (MMI scale) at the epicentral track. An attenuation relation between intensity and hypocentral distance is derived, which may be helpful to assess seismic hazards in this region.

2020 年 6 月 22 日，在印度-缅甸俯冲带附近的印度东北地区 (NER) 米佐拉姆邦的 Champhai 区发生了 5.5 级的严重有感地震。这次地震与群体活动有关。几乎在两个月内发生了 6 次 4.0-5.1 级地震和大约 16 次 3.0-3.9 级地震，这在米佐拉姆邦和邻近地区引起了恐慌。前一天，即 2020 年 6 月 21 日，发生在 Mw 5.5 的主震之前，发生在首都艾藻尔，距 Champhai 西北约 70 公里。所有这些事件都起源于浅层（~10-30 公里），并发生在俯冲印度板块的板内带。主震断层平面解表明走滑断层与印缅外楔（OIBW）中的横向垫断层相当匹配。对大约 46 个地点的主震的宏观地震调查显示，在震中轨道处 VIII（MMI 等级）的最大强度。推导出强度与震源距离之间的衰减关系，可能有助于评估该地区的地震灾害。