woodworth: geological expedition to brazil and chile. 119 



Geological formations of Chile, mainly from Sundt. 



Pleistocene. 



Eolian and other deposits of Atacama on 



the north. 

 Glacial till and gravels in the south. 



Eocene. 



Conglomerates and sandstones. 

 Lignitic group of Coronel. 



Cretaceous. 



Sandstones of Quiriquina Island, and 

 along the coast. 



Conglomerates, sandstones, and black 

 calcareous, fossiliferous shales of Co- 

 quimbo and the Pequenes Range. 



The Andes consist of deformed, squeezed up, and dissected beds of 

 the Tertiary and older rocks, with eruptives. The Longitudinal 

 Valley comprises Tertiary and possibly older beds overlain by lavas 

 and Pleistocene gravels the preglacial members of which series appar- 

 ently dip gently westward until cut off by the eastern fault of the 

 Coastal Cordillera. The Coastal Cordillera, made up of the meta- 

 morphic series and granite intrusions, is fringed by Cretaceous and 

 Eocene deposits in faulted relations with the older terrane. 



The Coastal Cordillera forms a long narrow tableland parallel to the 

 coast with an elevation from 1,200 to 1,500 feet, the flattish upper 

 surface of which is evidently a peneplain from which more recent beds 



