L. V. Dalton — Geology of Venezuela. 205 



of the Scottish Highlands, and exactly similar relation to the Archaean 

 complex below, it may be reasoned that they should be considered 

 as equivalent in age, and therefore forming, with the Guayana 

 complex, the most ancient rocks in Venezuela. 



North of the Orinoco we have in the Caribbean Hills and elsewhere 

 a series of gneissose and schistose rocks, named by Wall in 1860 

 the Caribbean Series. The group includes silvery mica-schists (not 

 infrequently mistaken for gold or silver ores), graphitic schists and 

 gneisses with banding of all degrees of fineness, whilst, in addition, 

 crystalline limestones occur in Eastern Venezuela. The thickness of 

 the group is not known with any certainty, but Mr. E. H. C. 

 Craig estimated it at less than 2,000 feet in Trinidad, though, owing 

 to crushing and complicated folding, the apparent thickness is much 

 greater. The age of these strata is unknown, but they generally 

 show distinct evidence of a sedimentary origin, notwithstanding that 

 some of the gneisses may be altered igneous (plutonic) rocks ; the 

 relation of the Cretaceous of Venezuela to them shows that they are 

 at least earlj^ Mesozoic, and may be Palaeozoic, or even Archaean, 

 while it is very possible that parts of the Andes are older than the 

 strata exposed in the Caribbean Hills. 



The series was suitably named by Wall, as the main range of the 

 Caribbean Hills is everywhere formed of these metamorphics, but 

 they occur also in Margarita and throughout the Andes, while in the 

 Llanos north of El Baul is an elevated area (known as la Galera) 

 with numerous hills of similar rocks. 



Next in age appear to be a group of red and yellow quartzites and 

 sandstones with varicoloured shales and slates, and a few black 

 bituminous limestones, often somewhat metamorphosed. These rocks 

 cover practically the whole of the elevated region round Barquisimeto 

 or Nueva Segovia (the Segovia Highlands), and the author therefore 

 suggests the name Segovia Group for them. From several localities 

 fossils (Ammonites, Inoceramus, etc.) have been obtained in them, 

 notably near Tocuyo (by Karsten) and in the Sierra de Perija 

 (Sievers), which show their age to range from Neocomian to Aptian 

 (Lower Cretaceous). 



In addition to their great development in the Segovia Highlands 

 the rocks constitute a great part of the Serrania Interior, both in the 

 Caracas and Cumana regions, and form both flanks of the Cordillera of 

 Merida, as well as part of the Sierra de Perija. 



Above the Segovia Group in scattered areas throughout the 

 Cordilleras there is a massive well-bedded limestone, with fossils 

 indicating an age equivalent to the Turonian or Senonian of Europe. 

 This limestone was studied by Dr. Sievers near Capacho in Tachira, 

 and named by him tlie Capacho Limestone. It occurs frequently in 

 the Cordillera of Merida, and is well seen to the east of Carache in the 

 Humocaro Hills, where it forms castellate masses and high cliffs and 

 gorges along the rivers. In the Segovia Highlands the Cordilleras of 

 San Luis and Agua Negra include large masses of this limestone, and 

 it occurs in the peninsula of Paraguana, but has been detected at only 

 a few points in the Serrania Interior south of Caracas. In the Sierra 

 de los Tageres it constitutes many of the ridges. 



