80 J. W. SPEN(:ER — GEOGRAPHICAL EVOLUTION OF CUBA. 



vening depressions reduced to 300 or 400 feet. The ridges are composed 

 of Tertiary limestones resting upon the Cretaceous deposits. 



The Santo Espiritu mountains, at a somewhat higher altitude than 

 the coast range, and extending inland, are also composed of Tertiary- 

 formations. The trend of the echeloned coast range is south 70° east. 

 Lookout peak, back of the city of Trinidad, is 740 feet high. Near its 



summit there are beds of fine con- 

 glomerate composed of rounded 

 quartz pebbles an inch in length. 

 There are also limestone pebbles 



N / „.M^^ 



SS^J^' 





FIGURE 5.-The coastal Chain of Tertiary ^hrCC timCS aS large. FrOm the dc- 

 Moiintains dislocated by Faults. cay of the fomiatioU the SUrfaCCS 



7=^= the northern side presents precipitous of tllC rOCks bcCOmC COVCrcd with 

 slopes, while the southern descent is gentle. ^^^^,^^ ^|^^^ j^^.g|^^ 1^^ mistaken for a 



more recent deposit. Other beds are soft white marly limestones. The 

 dip of the strata at Tjookout station is 15° or 20° east of south, but lower 

 down upon the flanks of the mountain the Cretaceous (?) limestones in- 

 cline at high angles toward the southwest. Three miles east of Trinidad 

 the Tertiary formations dip at 20° southeast. Tlie Tertiary rocks do not 

 exceed a few hundred feet in thickness, as they have suffered an enor- 

 mous amount of erosion. 



The different cliaracter of the Tertiary accumulations on the two sides 

 of the Trinidad mountains is notable, and may have arisen from the 

 direction of the currents or from the deposition of the two sets of beds 

 not having been synchronous. No attempt has been made to separate 

 the different members of the group, as the fossils are very scarce, those 

 found in the caves having been carried there at a recent day. The 

 Tertiary limestones are very much honeycombed by rain washes, and 

 they are further characterized by numerous large caves. Only fragments 

 of the overlying Matanzas marls remain upon the eroded surface of the 

 older Tertiary rocks, except near the coast. 



GEOGRAPHIC FEATURES OF THE TERTIARY PERIOD. 



In the earl}' part of the Tertiary j^eriod a long, narrow island extended 

 from the Trinidad mountains eastward. Between the Trinidad moun- 

 tams and those in the most western portion of Cuba there was a broad sea, 

 out of which rose a few islands. The depth of the submergence was vari- 

 able. At Matanzas it exceeded 1,300 feet and in the Sierra Maestra the 

 depression reaches at least 2,300 feet (Kimball). In some portions of 

 Cuba there is evidence that the land was high in the early Eocene, but 

 apparently depressed at the end of that period, which merged into the 

 Miocene. In places the fossils indicate, according to Salterain and Gabb, 



