40 SOUTHERN CALIFORNIA GEOLOGY 



guez Range and practically parallels the coast from 

 Westgate, east of Santa Monica, southward towards 

 San Diego. Some of the light jars and tremors which 

 have disturbed the tranquihty of Los Angeles in the 

 past may be accredited to this line of movement and 

 one of them in 1920 caused considerable attention. 



Past performances along this rift do not justify 

 alarming predictions as to its future. The Inglewood 

 shake of 1920 and possibly the Capistrano shake of 

 1812 may be attributed to movements along it. In 

 the first instance cited no dire results followed, and 

 the falling of the poorly constructed tower through 

 the church roof at San Juan Capistrano has been ex- 

 plained on another page. One can see that it would 

 have taken but a very minor tremor to have shaken 

 this building down. The rumbling of a modern truck 

 or the vibrations from the firing of a great naval gun 

 would have done it, had the tower existed today. 



The fact that the elongated fold of the Dominguez 

 Range, which is cut throughout its length by the Ingle- 

 wood fault, has retained its stores of oil and gas for 

 thousands of years might be interpreted by some to in- 

 dicate that the shocks along this line have never been 

 sufficiently great to open fractures for their escape. 

 Oil and gas in such pools are very volatile substances, 

 and are quick to leak out through any fracture in their 

 natural containers. These were perhaps the most 

 perfectly locked-in oil pools ever found in the State. 



Judging from past history, it cannot be said that 

 there is any great menace from the Inglew^ood line. 

 Its releases from strain have consisted of small ver- 

 tical movements, sometimes frightening, sometimes 

 slightly damaging, but at no time seriously dangerous. 



