SUMMARY OF THE SHOCKS T) 



SUMMARY OF THE SHOCKS. 



The earthquake of May 18th was the first disturbance which 

 took place in Upper Burma during the summer of 1912. Lt 

 occurred between 2-45 a.m. and 3 A.M. (B.S.T.)(') as far as can 

 be ascertained, and appears to have disturbed the western portions 

 of the Northern and Southern Shan States. It caused no appre- 

 ciable damage and probably did not exceed an intensity 01 \ on 

 the Rossi-Fore] scale. No records have been received of aftershocks 

 following this quake. 



The violent earthquake of May 21st appears to liave been fell 

 throughout the whole or greater pari of the Northern and Southern 

 Shan States, and the districts of Mandalay. Ruby Mines, Shwebo, 

 Sagaing, Lower Chindwin, Kyaukse, Myingyan, Meiktila. Magwe, 

 Vaniethin, Toungoo, and PegU as well as over Northern Siam. 

 The minimum area over which it was sensible approximates, there- 

 fore, 125, 000 square miles. In the central parts of this area, an 

 intensity of at least VII on the Hossi-Forel scale was attained, and 

 in some places loud Fumbling noises accompanied the shock. The 

 intensity appears to have died away rapidly, and in places like 

 Kani in the Lower Chindwin district, and in Pegu, only readied 

 degrees II or III on the Rossi- Forel scale. Unfortunately no exact 

 time data exist, and the nearest approach to accuracy possible is 

 to state that it took place about 3 p.m. (R.S.T.). This shock was 

 recorded by the Omori seismograph at Rangoon College, and by 

 the instruments at the meteorological stations throughout India. It 

 was followed by continuous aftershocks felt during the remainder 

 of that and the following day in Maymvo, Mandalay. Taunggyi. 

 Kyaukse and other places, and which gradually became fewer, until 

 the climax was reached by the great shock- of tin 1 morning of May 

 23rd, which was sensible over an area of 375.000 square miles 

 approximately, and disturbed recording instruments throughout the 

 world. 



This latter shock will be described first in the following pages. 

 It was followed by innumerable small aftershocks in Maw June, .Inly 

 and August, which gradually became fewer and finally ceased. 



Unhappily there are signs that the forces which caused the quakes 

 have not yet attained equilibrium, for on January 18th, 11)13, a 



1 Burma .Standard Time. 



