Earthquakes in Burma over the weekend have raised concerns that the tremors may have spread there from northern Thailand, where a quake struck on 5 May, the Thai Department of Mineral Resources says.
Officials detected three quakes with magnitudes on the Richter scale of between 2.6 and 3.8 on Saturday and Sunday.
One quake detected at 3.18am on Sunday measured 2.6. Its epicentre was in Burma, officially known as Myanmar, about nine km from Chiang Rai’s Mae Sai district in northern Thailand.
The quake was on the Mae Chan fault line, which passes Burma, Chiang Rai’s Mae Chan district and Laos.
The fault line is close to the spot in Chiang Rai where a 6.3 magnitude earthquake erupted on 5 May.
Officials believe some of the tremors detected over the weekend may relate to the Chiang Rai quake, said Thinnakon Thathong, chief of the mineral resource office in Lampang.
The concerns are based on the principle that when one fault line or crack in the earth’s crust moves, causing an earthquake, other nearby fault lines will move too.
Though there have been no reports of subsequent quakes on other fault lines in the northern provinces, an inspection has found fault lines in Burma have moved, which suggests they were linked, Mr Thinnakon said.
His department is monitoring other active fault lines to see whether they have been affected by the quake in Mae Lao district.
There have been more than 1,000 aftershocks reported in the area since 5 May, according to the department.
The 5 May earthquake, with its high magnitude and many aftershocks, was unusual.
Records suggest it had never happened before in the northern region, Mr Thinnakon said.
This article was originally published in the Bangkok Post on 19 May 2014.