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University of California Publications. 



[Geology 



ten feet, the latter amounted to as much or more, and the two 

 together represent the estimates of the height of the barrier as 

 seen from the south, estimates which range up to 20*4 feet." 



When we consider the general character of the movement 

 which took place at the time of this earthquake, Professor Suess' 

 explanation seems entirely inadequate. Is it possible that the 

 subsidence of a portion of the land due to the squeezing out of 

 the contained water could present the characteristics noticed 

 at the Rami of Cutch ? We have a well-defined scarp some fifty 

 miles in length and about twenty feet in elevation sharply divid- 

 ing the land which was depressed from the region not so affected ; 

 we find the subsidence was greatest at the scarp and diminished 

 towards the south, with no other scarp limiting its area; and 

 we find that the lake so formed was not merely a temporary 

 lake due to the sudden supply of water and quickly drained, but 

 that it remained as a permanent lake for some time and that it 

 is still occasionally flooded either by fresh water from the rains 

 and surrounding streams, or by salt water driven in from the 

 sea by the southwest monsoons, conditions which did not exist 

 before the earthquake. And we have Captain Baker's positive 

 statement that the Bund slopes downwards towards the north, 

 and his section shows the slope, which was, however, so gentle 

 that it could not have been detected by the eye alone. 



In view of our present knowledge, I think we may represent 

 very simply the movements which took place at the time of this 

 earthquake as follows : 



The Rann of Cutch, formerly below the sea level, was gradu- 

 ally raised by vertical forces which were stronger toward the 

 north. An elastic shearing strain was thus set up which finally 

 resulted in a rupture of the rock along an east and west line, 

 with an upward fling of the northern side to form the Bund, 

 and a corresponding downward fling of the southern side, to 

 form the lake, the total relative movement being about twenty 

 feet, practically the same as the relative horizontal displacement 

 at the time of the California earthquake. It seems rather strange 

 that Professor Suess, who pointed out so clearly the relations 

 of earthquakes to fault-lines, should not have seen that in this 



