SIGNIFICANCE OF LATE EARTHQUAKE EXPLAINED

"The earthquake of January 31, which was located as being off the coast of the North Western States by seismographic measurements, singularly occurred within five minutes of the hour at which the great earthquake of San Francisco on April 18, 1906 took place", declared Professor J. B. Woodworth '94, when interviewed by a CRIMSON reporter yesterday. "The San Francisco tragedy started at 5.12 A. M., while this quake was registered at 5.17 A. M., 120th meridian time.

Professor Woodworth stated that this tremor was not unforseen as geologists had been expecting a similar disturbance in this particular locality for several years. They were led to this forecast from the fact that the shock was centered in the belt between the great earthquake of Mount St. Elias in the region of Alaska, and the San Francisco district. The former disturbance, which occurred in 1899, was the greatest shock that has taken place in North America since the white man's occupancy, while the San Francisco disaster was a serious shakeup in the earth's crust. The section between these two districts, however, shows no signs of having ever been disturbed, and since it lies in the same belt it is natural that someday the crust was to settle down.

"It is only fortunate that this took place on the floor of the ocean", he declared. "For, had it occurred on the coast, such cities as Seattle and Portland would have been seriously affected".

"The character of the movement of the earth's crust can fairly be assumed to have been similar to that at the time of the San Francisco shock, in which the rocks at an unknown depth slipped horizontally past each other about 16 feet on a verticle plane. This formation, technically known as a 'fault', extends along the coast, nearly parallel to it, and stretches for a great distance on the ocean's bottom".

When questioned about the method of locating the center of the shock, Professor Woodworth outlined the system of "triangulation". Three seismographic stations are chosen well apart and the distances to the shock are read on the charts. These distances are then taken as respective radii and circles are drawn about the three stations. The point of intersection of these curves marks the location of the center of the shock, which in the recent quake, was estimated to be about 2775 miles form Cambridge