Strong and shallow M6.0 earthquake hits Mona Passage, Puerto Rico

A strong and shallow earthquake registered by the USGS as M6.0 hit Mona Passage, Puerto Rico at 03:23 UTC on September 24, 2019 (23:23 LT, September 23). The agency is reporting a depth of 10 km (6.2 miles). EMSC is reporting the same magnitude and depth.

The epicenter was located 67 km (42 miles) NNW of San Antonio (population 2 300), 69 km (43 miles) NNW of Isabela (population 12 505) and 73 km (45 miles) N of Aguadilla (population 16 073), Puerto Rico.

There are 540 000 people living within 100 km (62 miles).

2 664 000 people are estimated to have felt light shaking.

The USGS issued a green alert for shaking-related fatalities and economic losses. There is a low likelihood of casualties and damage.

Overall, the population in this region resides in structures that are resistant to earthquake shaking, though vulnerable structures exist. The predominant vulnerable building types are mud wall and informal (metal, timber, GI etc.) construction.

Recent earthquakes in this area have caused secondary hazards such as landslides that might have contributed to losses.

The quake was followed by M4.7 at 03:32 UTC, M3.1 at 03:43, M4.6 at 03:51 and M4.3 at 04:09.

Estimated population exposure to earthquake shaking

Selected cities exposed

Regional seismicity

Featured image credit: Google, TW/SAM