Five minor quakes, one of them a 3.6 magnitude, hit the northern province of Chiang Rai four times on Thursday morning. There were no reports of damage or casualties, the Thai Meteorological Department’s Earthquake Observation Division reported.
The first quake, measuring 3.6 on the Richter scale, occurred at 00.45am at tambon Dong Mada in Mae Lao district, two kilometres underground. The tremor was felt in Mae Lao, Muang, Phan and Mae Suai districts of Chiang Rai.
The second, a 1.9 magnitude quake, 3km underground, occurred 38 seconds after the first one in the area of tambon Chom Mok Kaew, Mae Lao district.
The third, a 0.9 magnitude quake, 4km underground, took place at 3.00am in tambon Chom Mok Kaew in Mae Lao.
A 1.8 magnitude quake, the fourth, 2km underground, occurred at 3.18am in tambon Dong Mada, Mae Lao.
The 5th quake of a 2.4 magnitude, 4km underground, happened at 7.48am in tambon Chom Mok Kaew, Mae Lao.
No damage or casualties were reported.
New Fault Line in Chiang Rai Province
In 2019, the Department of Mineral Resources announced the finding of a new active seismic fault in Chiang Mai province’s Wiang Haeng area, naming it the Wiang Haeng fault line.
Wiang Haeng is Thailand’s 16th recognised fault line, and it is expected to create a series of earthquakes with a maximum magnitude of 6.7 during the next 50 years after being dormant for more than 2,000 years.
The department’s deputy chief, Montri Luengingkasoot, told a news conference on Thursday that Wiang Haeng was added to the department’s list of active faults after a study discovered considerable tectonic plate movement there.
He went on to say that Thailand has more active fault lines that have yet to be detected.
The department’s team studied the Wiang Haeng fault line and discovered new evidence of a 6.7 magnitude earthquake roughly 2,000 years ago along the Thai-Myanmar border in Wiang Haeng district.
Thailand has 15 fault lines that go through 22 regions. Scientists are especially concerned about the Mae Chan fault line, which might cause a magnitude 7 earthquake in the near future. It is approximately 100 km long and runs across the provinces of Chiang Mai and Chiang Rai.
The Sri Sawat and Three Pagoda fault lines, which run across the western region and are near to the country’s largest artificial water catchment, the Sringarind dam in Kanchanaburi province, are also under intense scrutiny.
Suwith Kosuwan, director of the department’s Geohazards Division, said the Wiang Haeng fault is around 100 km long and runs through Chiang Mai’s Samoeng district.
She stated that the projected 6.7 earthquake is considered significant and could cause damage comparable to the Chiang Rai earthquake five years ago.
A 6.3 magnitude earthquake struck Chiang Rai‘s Mae Lao district on May 5, 2014, causing significant damage to essential infrastructure and dwellings. The activity on the Mae Lao fault line, which is projected to create quakes of up to 6.5 magnitude, caused the quake, according to the department.
“We believe that within the next 50 years, the newly discovered fault will produce an earthquake with a maximum magnitude of 6.7, which is very close to the level of Mae Lao,” she said.
Due to heavy rain, the agency also issued landslip warnings for Chiang Mai, Mae Hong Son, Tak Phitsanulok, and Chanthaburi provinces on Thursday. The department is keeping a close eye on the situation.
An official noted that a recent landslip in Tak province’s Tha Song Yang district, which killed one person and left another missing, occurred in a remote spot that the government does not regularly monitor.