QUETTA EARTHQUAKE

King Country Chronicle, Volume XXIX, Issue 4747, 17 September 1935, Page 2

QUETTA EARTHQUAKE

BARELY THIRTY SECONDS. The Quetta earthquake last May, in which over 30,000 people lost their lives, may have the effect of ending the earthquake menace in the Quetta area for a long time to come, says the Daily Telegraph. This is the conclusion reached in the official account of the disaster which has been issued by the India Office. The author of the report, Mr; W. D. West, of the Geological Survey of India, says that a striking feature of the shock was that it lasted barely half a minute. ' s

"During that time the ground was viciously shaken in a horizonal plane at a high speed. The motion was described by many as being like a terrier shaking a rat. The intensity of the shock was such that it was reported to have thrown, the seismograph at Calcutta out of adjustment, though situated at a distance of some 1400 miles from Quetta." The earthquake, he adds, had ho connection with volcanic action, "and the inhabitants of Baluchistan may rest assured that there is not the slightest likelihood of volcanic activity breaking out in this part of India." In explanation of this statement, he says that the Himalayas were once the site of a long shallow sea in which soft marine deposits were laid.

"Latterly, during comparatively recent times, the stable continental area of Central Asia moved towards India* with the result that the soft marine deposits in between becamfe compressed and. folded into the mountains that we see at the present day, and which surround India oh its north-west, north, and north-east sides. The movement may be likened to the jaws of a vice closing and compressing some soft material in between.

Moving im Jerks.

"At first the 'rocks folded. Then, when the compression becomes more acute, they yield by fracturing, and a large mass of rock, perhaps several cubic miles in volume, may become driven over another mass in front of it. This movement very probably takes place in jerks, and it is generally believed that it is some such sudden movement which is the cause of the great majority of earthquakes.

"If the movement • which caused the recent earthquake be regarded as hav*ing afforded relief to the accumulated strains within the rocks of that area, then further earthquakes are unlikely to be located again along the QuettaMastung line for a long time to come. "Should more earthquakes visit Baluchistan in the near future, the probability is that they will be located in some other part of the country where the strains have not been relieved by the present earthquake, though, of course, they may be felt to some extent at Quetta." It was explained recently by Mr. J. Shaw, the Birmingham seismoio : gist, that the series of minor shocks which has occurred in Quetta sinc6 the disaster is due to the settlement of the ground following the major upheaval.