196 JR. T. Hill — Tertiary and later 



Art. XXYITI. — Notes on the Tertiary and later History of 

 the Island of Cuba • by Eobert T. Hill.* 



This paper is an abstract of a more extensive manuscript 

 report made to Prof. Alexander Agassiz and is based upon a 

 reconnoissance of most of the Island of Cuba, with the ex- 

 ception of the mountainous region of the Sierra Maestra the 

 geology of which has been partially presented by Kimball in 

 this Journal,f and studied contemporaneously with the writer's 

 observations by Prof. Clarence King. My reconnoissance was 

 accompanied by critical studies of certain typical localities at 

 Havana, Matanzas, Villa Clara, Gibara, Baracoa and the vicin- 

 ity of Cape Mayci. 



The stratigraphy, age, and general relations of the rocks of 

 Cuba have been set forth by De Castro,;}: and Salterain§ to- 

 gether with a good geologic map. 



It is not necessary in this paper to dwell upon the details 

 already presented. The geological structure of the Island con- 

 sists of four stratigraphic units, to wit : (1) The Pre-Tertiary, 

 Metamorphic and Igneous Foundation ; (2) The Pre-Tertiary 

 sedimentaries, mostly of Cretaceous age; (3) The Tertiary 

 limestones ; and, (4) The modern elevated coral reefs. 



1. The Metamorphic and Igneous Foundation. The con- 

 temporary investigations of Prof. King in the Sierra Maestra 

 will no doubt throw more light upon these formations than I 

 can give. 



These older rocks consist of diorites, serpentines, schists and 

 granites as reported by Kimball from Santiago ; of serpen- 

 tines, green stone, porphyry and basic igneous rocks, fragments 

 of which are brought down by the rivers of the north side of 

 the east end of the Island ; of serpentine and metamorphic 

 rocks, with little quartz, as seen underneath the limestone in 

 the vicinity of Yilla Clara ; and of serpentine, old volcanic 

 material and tuffs, as seen back of Havana. They are exposed 

 by erosion at various points throughout the island, but, with 

 the exception of the Santiago region, seldom if ever, form the 

 rocks of the immediate coast. They now underlie nearly every 



* By permission of Prof. Alexander Agassiz through whose generosity the 

 observations set forth in this paper were made possible. 



f Geological Relations and Genesis of the Specular Iron Ores of Santiago de 

 Cuba. This Journal, Dec, 1884. 



% Pruebas Paleontologicas de que la Isla de Cuba ha Estado Unida al Conti- 

 nente Americano y breve idea de su Constitucion Geologica, por Don Manuel 

 Fernandez de Castro. Discurso pronunciaclo en el cuarto Congreso international 

 de Americanistas celebrado en Madrid en Setiembre de 1881. 



§ Apuntes para una Description Fisico-geologica de las Jurisdieciones de la 

 Habana y Guanabacoa, etc. por D. Pedro Salterain y Legarra, etc., Madrid, 1890. 



