REPORT OF THE DIRECTOR I915 



103 



The disturbance came suddenly, without any 

 warning that was sensed by those on the ground 

 so that they could secure their safety, and was 

 over probably in a couple of minutes from its 

 start. Accounts of the eye witnesses are con- 

 flicting as to details ; but there seems little doubt 

 that the first distinct manifestations of the dis- 

 turbance were at the creek bed. One of the wit- 

 nesses whose attention was turned in that direc- 

 tion, saw the waters rise and rush out of the 

 channel in a great flood, of which abundant evi- 

 dences were to be found for a long time after- 

 ward in the leveled appearance of the adjoining 

 fields. So quickly were the waters discharged 

 that fish were stranded on the bottom. The up- 

 heaval was accompanied by tremors and settle- 

 ment of the higher land to the west, the ground 

 rocking as if it were in the throes of an earth- 

 quake. The subsidence was effected in blocks or 

 strips, elongated, in a north-south direction, the 

 blocks being uniformly tilted toward the west, 

 probably as the result of the drag of the wet clay 

 below in its flow toward the creek. 



With the rupture of the surface clays at the 

 creek by their upthrust of 20 feet or so, a way of 

 escape was opened for the lower fluid layer 

 which under pressure then flowed out onto the 

 flats east of the old channel. The clays exposed 

 in the dry creek bed were turned on edge; they 

 consisted of tough, coherent brown clay little 

 softened by their continuous contact with water. 

 The flowed clay on the other hand was of blue 

 color, very wet and greasy, without the. definite 

 lamination that it shows when in place ; or else 

 with the lamination much contorted. 



It is apparent from the features already set 

 forth that the creek channel constituted a zone of 

 weakness and was one of the essential causes of 

 the disturbances. There was little evidence, 

 however, to indicate material deepening of the 

 channel by erosion just previous to the event, 

 although it was a time of heavy rains and high 

 waters. It was noticed that the clays were 



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