CHIANG RAI, THAILAND – A magnitude 3.0 earthquake early on 19 March shook Mae Suai district and was clearly felt across parts of Chiang Rai, prompting close monitoring by authorities due to its shallow 2‑kilometre depth.
Quake shortly after sunrise
The earthquake monitoring division of the Thailand Meteorological Department (TMD) recorded the tremor at 05:31, with its epicentre in Tambon Mae Suai, Mae Suai district, Chiang Rai province. According to the agency, the focus lay at just 2 kilometres below the surface.
Officials explained that this shallow depth meant the shaking was perceived more strongly in many places than would be expected from a quake of this moderate magnitude. No damage was initially reported, but monitoring stations said they were paying particular attention to the event because of the shallow source.
How strongly Mae Suai residents felt the shaking
From areas near the epicentre, residents in single-storey houses reported that they had clearly felt the quake. Around the Khlong Thom Mae Suai market area near a PT petrol station, people in a two-storey house described pronounced swaying and noises.
They also reported a noticeable vibration lasting about 5 to 7 seconds. Locals said the intensity of the movement surprised them given the relatively low magnitude.
Tremor noticeable in Chiang Rai city
In Mueang Chiang Rai city, several neighbourhoods reported perceptible shaking. At a building of the municipal fire brigade in Rop Wiang, staff noted a brief tremor lasting about 1 second.
From Pa O Don Chai, residents in a two-storey house described how their bed shook.
“The bed shook very strongly,”
said a resident, describing the brief but intense movement.
Reports from Phan district
Although Phan district lay farther from the epicentre, reports of shaking also came in from homes and accommodation facilities there. In the Sai Khao area, residents of a dormitory of the Rajamangala University of Technology Lanna, Chiang Rai, said the building and ground vibrated for about 3 seconds.
From San Klang, witnesses described the jolt as sudden and forceful.
“It felt like a hard bump – as if someone falls out of a bed on the second floor,”
said one resident.
Shaking felt as far as Chiang Mai
The tremor was even perceived outside Chiang Rai, which some residents found unexpected. From San Sai Noi in Chiang Mai province, a few people reported mild dizziness.
These accounts suggested that the seismic waves were still noticeable in parts of the wider region. The reports also indicated that even a moderate quake could be felt over considerable distances when it is shallow.
Geologists point to active Mae Suai fault
Geologically, the epicentre lay on the Mae Suai subsidiary fault, which forms part of the Mae Lao–Mae Suai fault zone running in a northeast–southwest direction. After the major magnitude 6.3 earthquake in Phan in 2014, this structure was studied more intensively.
Field studies in the following years helped define the active fault zone more clearly. Researchers have since classified the area as one of the key seismic structures in northern Thailand.
Why even small quakes are taken seriously
Geologists described the Mae Suai subsidiary fault as about 30 kilometres long and characterised it as a left-lateral strike-slip fault. According to their assessments, it is capable of repeatedly generating small to medium-sized earthquakes.
In the same area, a magnitude 3.6 quake had already been recorded on 5 August 2017, which was likewise attributed to movement along this subsidiary fault. Experts said such events underline the ongoing activity of the structure.
No damage reported – authorities stay on alert
By late morning, authorities said there were still no reports of damage to buildings, homes or critical infrastructure. Inspections around the affected communities did not reveal any immediate structural problems.
Monitoring centres announced that they would continue to closely track the situation. They pledged to inform the public immediately in the event of aftershocks or new findings related to the Mae Suai fault activity.